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• IIS SSL Certificate Renewal Pain

  - by Rick Strahl

  I’m in the middle of my annual certificate renewal for the West Wind site and I can honestly say that I hate IIS’s certificate system.  When it works it’s fine, but when it doesn’t man can it be a pain. Because I deal with public certificates on my site merely once a year, and you have to perform the certificate dance just the right way, I seem to run into some sort of trouble every year, thinking that Microsoft surely must have addressed the issues I ran into previously – HA! Not so. Don’t ever use the Renew Certificate Feature in IIS! The first rule that I should have never forgotten is that certificate renewals in IIS (7 is what I’m using but I think it’s no different in 7.5 and 8), simply don’t work if you’re submitting to get a public certificate from a certificate authority. I use DNSimple for my DNS domain management and SSL certificates because they provide ridiculously easy domain management and good prices for SSL certs – especially wildcard certificates, which is what I use on west-wind.com. Certificates in IIS can be found pegged to the machine root. If you go into the IIS Manager, go to the machine root the tree and then click on certificates and you then get various certificate options: Both of these options create a new Certificate request (CSR), which is just a text file. But if you’re silly enough like me to click on the Renew button on your old certificate, you’ll find that you end up generating a very long Certificate Request that looks nothing like the original certificate request and the format that’s used for this is not accepted by most certificate authorities. While I’m not sure exactly what the problem is, it simply looks like IIS is respecting none of your original certificate bit size choices and is generating a huge certificate request that is 3 times the size of a ‘normal’ certificate request. The end result is (and I’ve done this at least twice now) is that the certificate processor is likely to fail processing those renewals. Always create a new Certificate While it’s a little more work and you have to remember how to fill out the certificate request properly, this is the safe way to make sure your certificate generates properly. First comes the Distinguished Name Properties dialog: Ah yes you have to love the nomenclature of this stuff. Distinguished name, Common name – WTF is a common name? It doesn’t look common to me! Make sure this form gets filled out correctly. Common NameThis is the domain name of the Web site. In my case I’m creating a wildcard certificate so I’m using the * prefix. If you’re purchasing a certificate for a specific domain use www.west-wind.com or store.west-wind.com for example. Make sure this matches the EXACT domain you’re trying to use secure access on because that’s all the certificate is going to work on unless you get a wildcard certificate. Organization Is the name of your company or organization. Depending on the kind of certificate you purchase this name will show up on your certificate. Most low end SSL certificates (ie. those that cost under $100 for single domains) don’t list the organization, the higher signature certificates that also require extensive validation by the cert authority do. Regardless you should make sure this matches the right company/organization. Organizational Unit This can be anything. Not really sure what this is for, but traditionally I’ve always set this to Web because – well this is a Web thing after all right? I’ve never seen this used anywhere that I can tell other than to internally reference the cert. State and CountryPretty obvious. Should reflect the location of the business/organization/person or site.   Next you have to configure the bit size used for the certificate: The default on this dialog is 1024, but I’ve found that most providers these days request a minimum bit length of 2048, as did my DNSimple provider. Again check with the provider when you submit to make sure. Bit length mismatches can cause problems if you use a size that isn’t supported by the provider. I had that happen last year when I submitted my CSR and it got rejected quite a bit later, when the certs usually are issued within an hour or less. When you’re done here, the certificate is saved to disk as a .txt file and it should look something like this (this is a 2048 bit length CSR):-----BEGIN NEW CERTIFICATE REQUEST----- MIIEVGCCAz0CAQAwdjELMAkGA1UEBhMCVVMxDzANBgNVBAgMBkhhd2FpaTENMAsG A1UEBwwEUGFpYTEfMB0GA1UECgwWV2VzdCBXaW5kIFRlY2hub2xvZ2llczEMMAoG B1UECwwDV2ViMRgwFgYDVQQDDA8qLndlc3Qtd2luZC5jb20wggEiMA0GCSqGSIb3 DQEBAQUAA4IBDwAwggEKAoIBAQDIPWOFMkMVRp2Ftj9w/cCVV4OYYhoZYtl+8lTk oqDwKca0xWHLgioX/9v0rZLS6a82MHqKEBxVXu+cuCmSE4AQtB/1YH9lS4tpc/be OZDvnTotP6l4MCEzzAfROcw4CiIg6X0RMSnl8IATAvv2V5LQM9TDdt9oDdMpX2IY +vVC9RZ7PMHBmR9kwI2i/lrKitzhQKaHgpmKcRlM6iqpALUiX28w5HJaDKK1MDHN 607tyFJLHijuJKx7PdTqZYf50KkC3NupfZ2avVycf18Q13jHWj59tvwEOczoVzRL l4LQivAqbhyiqMpWnrZunIOUZta5aGm+jo7O1knGWJjxuraTAgMBAAGgggGYMBoG CisGAQQBgjcNAgMxDBYKNi4yLjkyMDAuMjA0BgkrBgEEAYI3FRQxJzAlAgEFDAZS QVNYUFMMC1JBU1hQU1xSaWNrDAtJbmV0TWdyLmV4ZTByBgorBgEEAYI3DQICMWQw YgIBAR5aAE0AaQBjAHIAbwBzAG8AZgB0ACAAUgBTAEEAIABTAEMAaABhAG4AbgBl AGwAIABDAHIAeQBwAHQAbwBnAHIAYQBwAGgAaQBjACAAUAByAG8AdgBpAGQAZQBy AwEAMIHPBgkqhkiG9w0BCQ4xgcEwgb4wDgYDVR0PAQH/BAQDAgTwMBMGA1UdJQQM MAoGCCsGAQUFBwMBMHgGCSqGSIb3DQEJDwRrMGkwDgYIKoZIhvcNAwICAgCAMA4G CCqGSIb3DQMEAgIAgDALBglghkgBZQMEASowCwYJYIZIAWUDBAEtMAsGCWCGSAFl AwQBAjALBglghkgBZQMEAQUwBwYFKw4DAgcwCgYIKoZIhvcNAwcwHQYDVR0OBBYE FD/yOsTbXE+GVFCFMmldzQvyloz9MA0GCSqGSIb3DQEBBQUAA4IBAQCK6LlsCuIM 1AU0niB6QZ9v0FTsGFxP1dYvVUnJyY6VEKNiGFiQjZac7UCs0p58yScdXWEFOE8V OsjAYD3xYNc05+ckyD67UHRGEUAVB9RBvbKW23KeR/8kBmEzc8PemD52YOgExxAJ 57xWmAwEHAvbgYzQvhO8AOzH3TGvvHbg5UKM1pYgNmuwZq5DkL/IDoeIJwfk/wrI wghNTuxxIFgbH4YrgLgv4PRvrS/LaTCRBdboaCgzATMczaOb1nd/DVNR+3fCtMhM W0psTAjzRbmXF3nJyAQa7jF/52gkY0RfFX2lG5tJnG+XDsVNvKNvh9Qa5Tlmkm06 ILKCm9ciWCKk -----END NEW CERTIFICATE REQUEST----- You can take that certificate request and submit that to your certificate provider. Since this is base64 encoded you can typically just paste it into a text box on the submission page, or some providers will ask you to upload the CSR as a file. What does a Renewal look like? Note the length of the CSR will vary somewhat with key strength, but compare this to a renewal request that IIS generated from my existing site:-----BEGIN NEW CERTIFICATE REQUEST----- MIIPpwYFKoZIhvcNAQcCoIIPmDCCD5QCAQExCzAJBgUrDgMCGgUAMIIIqAYJKoZI hvcNAQcBoIIImQSCCJUwggiRMIIH+gIBADBdMSEwHwYDVQQLDBhEb21haW4gQ29u dHJvbCBWYWxpFGF0ZWQxHjAcBgNVBAsMFUVzc2VudGlhbFNTTCBXaWxkY2FyZDEY MBYGA1UEAwwPKi53ZXN0LXdpbmQuY29tMIGfMA0GCSqGSIb3DQEBAQUAA4GNADCB iQKBgQCK4OuIOR18Wb8tNMGRZiD1c9X57b332Lj7DhbckFqLs0ys8kVDHrTXSj+T Ye9nmAvfPpZmBtE5p9qRNN79rUYugAdl+qEtE4IJe1bRfxXzcKa1SXa8+TEs3zQa zYSmcR2dDuC8om1eAdeCtt0NnkvANgm1VLwGOor/UHMASaEhCQIDAQABoIIG8jAa BgorBgEEAYI3DQIDMQwWCjYuMi45MjAwLjIwNAYJKwYBBAGCNxUUMScwJQIBBQwG UkFTWFBTDAtSQVNYUFNcUmljawwLSW5ldE1nci5leGUwZgYKKwYBBAGCNw0CAjFY MFYCAQIeTgBNAGkAYwByAG8AcwBvAGYAdAAgAFMAdAByAG8AbgBnACAAQwByAHkA cAB0AG8AZwByAGEAcABoAGkAYwAgAFAAcgBvAHYAaQBkAGUAcgMBADCCAQAGCSqG SIb3DQEJDjGB8jCB7zAOBgNVHQ8BAf8EBAMCBaAwDAYDVR0TAQH/BAIwADA0BgNV 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+XZ8bhM7vsAS+pZionR4MyuQ0mYIt/lDcsZVZ91KxTsIm8rNMkkYGFoSIXjQ0+0t CbxMF0i2qnpmNRpA6PU8l7lxxvPkplsk9KB8QIPFrR5p/i/SUAd9vECWh5+/ktlc rfFP2PK7XcEwWizsvMrNqLyvQVNXSUPTMYIBrzCCAasCAQEwgYcwcjELMAkGA1UE BhMCR0IxGzAZBgNVBAgTEkdyZWF0ZXIgTWFuY2hlc3RlcjEQMA4GA1UEBxMHU2Fs Zm9yZDEaMBgGA1UEChMRQ09NT0RPIENBIExpbWl0ZWQxGDAWBgNVBAMTD0Vzc2Vu dGlhbFNTTCBDQQIRAO7UTVPkm+2Sbks59IdptaUwCQYFKw4DAhoFADANBgkqhkiG 9w0BAQEFAASCAQB8PNQ6bYnQpWfkHyxnDuvNKw3wrqF2p7JMZm+SuN2qp3R2LpCR mW2LrGtQIm9Iob/QOYH+8houYNVdvsATGPXX2T8gzn+anof4tOG0vCTK1Bp9bwf9 MkRP+1c8RW/vkYmUW4X5/C+y3CZpMH5dDTaXBIpXFzjX/fxNpH/rvLzGiaYYL3Cn OLO+aOADr9qq5yoqwpiYCSfYNNYKTUNNGfYIidQwYtbHXEYhSukB2oR89xD2sZZ4 bOqFjUPgTa5SsERLDDeg3omMKiIXVYGxlqBEq51Kge6IQt4qQV9P9VgInW7cWmKe dTqNHI9ri3ttewdEnT++TKGKKfTjX9SR8Waj -----END NEW CERTIFICATE REQUEST----- Clearly there’s something very different between this an my original request! And it didn’t work. IIS creates a custom CSR that is encoded in a format that no certificate authority I’ve ever used uses. If you want the gory details of what’s in there look at this ServerFault question (thanks to Mika in the comments). In the end it doesn’t matter  though – no certificate authority knows what to do with this CSR. So create a new CSR and skip the renewal. Always! Use the same Server Keep in mind that on IIS at least you should always create your certificate on a single server and then when you receive the final certificate from your provider import it on that server. IIS tracks the CSR it created and requires it in order to import the final certificate properly. So if for some reason you try to install the certificate on another server, it won’t work. I’ve also run into trouble trying to install the same certificate twice – this time around I didn’t give my certificate the proper friendly name and IIS failed to allow me to assign the certificate to any of my Web sites. So I removed the certificate and tried to import again, only to find it failed the second time around. There are other ways to fix this, but in my case I had to have the certificate re-issued to work – not what you want to do. Regardless of what you do though, when you import make sure you do it right the first time by crossing all your t’s and dotting your i's– it’ll save you a lot of grief! You don’t actually have to use the server that the certificate gets installed on to generate the CSR and first install it, but it is generally a good idea to do so just so you can get the certificate installed into the right place right away. If you have access to the server where you need to install the certificate you might as well use it. But you can use another machine to generated the and install the certificate, then export the certificate and move it to another machine as needed. So you can use your Dev machine to create a certificate then export it and install it on a live server. More on installation and back up/export later. Installing the Certificate Once you’ve submitted a CSR request your provider will process the request and eventually issue you a new final certificate that contains another text file with the final key to import into your certificate store. IIS does this by combining the content in your certificate request with the original CSR. If all goes well your new certificate shows up in the certificate list and you’re ready to assign the certificate to your sites. Make sure you use a friendly name that matches domain name of your site. So use *.mysite.com or www.mysite.com or store.mysite.com to ensure IIS recognizes the certificate. I made the mistake of not naming my friendly name this way and found that IIS was unable to link my sites to my wildcard certificate. It needed to have the *. as part of the certificate otherwise the Hostname input field was blanked out. Changing the Friendly Name If you by accidentally used an invalid friendly name you can change it later in the Windows certificate store. Bring up a Run Box Type MMC File | Add/Remove Snap In Add Certificates | Computer Account | Local Computer Drill into Certificates | Personal | Certificates Find your Certificate | Right Click | Properties Edit the Friendly Name | Click OK Backing up your Certificate The first thing you should do once your certificate is successfully installed is to back it up! In case your server crashes or you otherwise lose your configuration this will ensure you have an easy way to recover and reinstall your certificate either on the same server or a different one. If you’re running a server farm or using a wildcard certificate you also need to get the certificate onto other machines and a PFX file import is the easiest way to do this. To back up your certificate select your certificate and choose Export from the context or sidebar menu: The Export Certificate option allows you to export a password protected binary file that you can import in a single step. You can copy the resulting binary PFX file to back up or copy to other machines to install on. Importing the certificate on another machine is as easy as pointing at the PFX file and specifying the password. IIS handles the rest. Assigning a new certificate to your Site Once you have the new certificate installed, all that’s left to do is assign it to your site. In IIS select your Web site and bring up the Site Bindings from the right sidebar. Add a new binding for https, bind it to port 443, specify your hostname and pick the certificate from the pick list. If you’re using a root site make sure to set up your certificate for www.yoursite.com and also for yoursite.com so that both work properly with SSL. Note that you need to explicitly configure each hostname for a certificate if you plan to use SSL. Luckily if you update your SSL certificate in the following year, IIS prompts you and asks whether you like to update all other sites that are using the existing cert to the newer cert. And you’re done. So what’s the Pain? So, all of this is old hat and it doesn’t look all that bad right? So what’s the pain here? Well if you follow the instructions and do everything right, then the process is about as straight forward as you would expect it to be. You create a cert request, you import it and assign it to your sites. That’s the basic steps and to be perfectly fair it works well – if nothing goes wrong. However, renewing tends to be the problem. The first unintuitive issue is that you simply shouldn’t renew but create a new CSR and generate your new certificate from that. Over the years I’ve fallen prey to the belief that Microsoft eventually will fix this so that the renewal creates the same type of CSR as the old cert, but apparently that will just never happen. Booo! The other problem I ran into is that I accidentally misnamed my imported certificate which in turn set off a chain of events that caused my originally issued certificate to become uninstallable. When I received my completed certificate I installed it and it installed just fine, but the friendly name was wrong. As a result IIS refused to assign the certificate to any of my host headered sites. That’s strike number one. Why the heck should the friendly name have any effect on the ability to attach the certificate??? Next I uninstalled the certificate because I figured that would be the easiest way to make sure I get it right. But I found that I could not reinstall my certificate. I kept getting these stop errors: "ASN1 bad tag value met" that would prevent the installation from completion. After searching around for this error and reading countless long messages on forums, I found that this error supposedly does not actually mean the install failed, but the list wouldn’t refresh. Commodo has this to say: Note: There is a known issue in IIS 7 giving the following error: "Cannot find the certificate request associated with this certificate file. A certificate request must be completed on the computer where it was created." You may also receive a message stating "ASN1 bad tag value met". If this is the same server that you generated the CSR on then, in most cases, the certificate is actually installed. Simply cancel the dialog and press "F5" to refresh the list of server certificates. If the new certificate is now in the list, you can continue with the next step. If it is not in the list, you will need to reissue your certificate using a new CSR (see our CSR creation instructions for IIS 7). After creating a new CSR, login to your Comodo account and click the 'replace' button for your certificate. Not sure if this issue is fixed in IIS 8 but that’s an insane bug to have crop up. As it turns out, in my case the refresh didn’t work and the certificate didn’t show up in the IIS list after the reinstall. In fact when looking at the certificate store I could see my certificate was installed in the right place, but the private key is missing which is most likely why IIS is not picking it up. It looks like IIS could not match the final cert to the original CSR generated. But again some sort of message to that affect might be helpful instead of ASN1 bad tag value met. Recovering the Private Key So it turns out my original problem was that I received the published key, but when I imported the private key was missing. There’s a relatively easy way to recover from this. If your certificate doesn’t show up in IIS check in the certificate store for the local machine (see steps above on how to bring this up). If you look at the certificate in Certificates/Personal/Certificates make sure you see the key as shown in the image below: if the key is missing it means that the certificate is missing the private key most likely. To fix a certificate you can do the following: Double click the certificate Go to the Details Tab Copy down the Serial number You can copy the serial number from the area blurred out above. The serial number will be in a format like ?00 a7 9b a1 a4 9d 91 63 57 d6 9f 26 b8 ee 79 b5 cb and you’ll need to strip out the spaces in order to use it in the next step. Next open up an Administrative command prompt and issue the following command: certutil -repairstore my 00a79ba1a49d916357d69f26b8ee79b5cb You should get a confirmation message that the repair worked. If you now go back to the certificate store you should now see the key icon show up on the certificate. Your certificate is fixed. Now go back into IIS Manager and refresh the list of certificates and if all goes well you should see all the certificates that showed in the cert store now: Remember – back up the key first then map to your site… Summary I deal with a lot of customers who run their own IIS servers, and I can’t tell you how often I hear about botched SSL installations. When I posted some of my issues on Twitter yesterday I got a hell storm of “me too” responses. I’m clearly not the only one, who’s run into this especially with renewals. I feel pretty comfortable with IIS configuration and I do a lot of it for support purposes, but the SSL configuration is one that never seems to go seamlessly. This blog post is meant as reminder to myself to read next time I do a renewal. So I can dot my i's and dash my t’s before I get caught in the mess I’m dealing with today. Hopefully some of you find this useful as well.© Rick Strahl, West Wind Technologies, 2005-2014Posted in IIS7  Security   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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• Toorcon14

  - by danx

  Toorcon 2012 Information Security Conference San Diego, CA, http://www.toorcon.org/ Dan Anderson, October 2012 It's almost Halloween, and we all know what that means—yes, of course, it's time for another Toorcon Conference! Toorcon is an annual conference for people interested in computer security. This includes the whole range of hackers, computer hobbyists, professionals, security consultants, press, law enforcement, prosecutors, FBI, etc. We're at Toorcon 14—see earlier blogs for some of the previous Toorcon's I've attended (back to 2003). This year's "con" was held at the Westin on Broadway in downtown San Diego, California. The following are not necessarily my views—I'm just the messenger—although I could have misquoted or misparaphrased the speakers. Also, I only reviewed some of the talks, below, which I attended and interested me. MalAndroid—the Crux of Android Infections, Aditya K. Sood Programming Weird Machines with ELF Metadata, Rebecca "bx" Shapiro Privacy at the Handset: New FCC Rules?, Valkyrie Hacking Measured Boot and UEFI, Dan Griffin You Can't Buy Security: Building the Open Source InfoSec Program, Boris Sverdlik What Journalists Want: The Investigative Reporters' Perspective on Hacking, Dave Maas & Jason Leopold Accessibility and Security, Anna Shubina Stop Patching, for Stronger PCI Compliance, Adam Brand McAfee Secure & Trustmarks — a Hacker's Best Friend, Jay James & Shane MacDougall MalAndroid—the Crux of Android Infections Aditya K. Sood, IOActive, Michigan State PhD candidate Aditya talked about Android smartphone malware. There's a lot of old Android software out there—over 50% Gingerbread (2.3.x)—and most have unpatched vulnerabilities. Of 9 Android vulnerabilities, 8 have known exploits (such as the old Gingerbread Global Object Table exploit). Android protection includes sandboxing, security scanner, app permissions, and screened Android app market. The Android permission checker has fine-grain resource control, policy enforcement. Android static analysis also includes a static analysis app checker (bouncer), and a vulnerablity checker. What security problems does Android have? User-centric security, which depends on the user to grant permission and make smart decisions. But users don't care or think about malware (the're not aware, not paranoid). All they want is functionality, extensibility, mobility Android had no "proper" encryption before Android 3.0 No built-in protection against social engineering and web tricks Alternative Android app markets are unsafe. Simply visiting some markets can infect Android Aditya classified Android Malware types as: Type A—Apps. These interact with the Android app framework. For example, a fake Netflix app. Or Android Gold Dream (game), which uploads user files stealthy manner to a remote location. Type K—Kernel. Exploits underlying Linux libraries or kernel Type H—Hybrid. These use multiple layers (app framework, libraries, kernel). These are most commonly used by Android botnets, which are popular with Chinese botnet authors What are the threats from Android malware? These incude leak info (contacts), banking fraud, corporate network attacks, malware advertising, malware "Hackivism" (the promotion of social causes. For example, promiting specific leaders of the Tunisian or Iranian revolutions. Android malware is frequently "masquerated". That is, repackaged inside a legit app with malware. To avoid detection, the hidden malware is not unwrapped until runtime. The malware payload can be hidden in, for example, PNG files. Less common are Android bootkits—there's not many around. What they do is hijack the Android init framework—alteering system programs and daemons, then deletes itself. For example, the DKF Bootkit (China). Android App Problems: no code signing! all self-signed native code execution permission sandbox — all or none alternate market places no robust Android malware detection at network level delayed patch process Programming Weird Machines with ELF Metadata Rebecca "bx" Shapiro, Dartmouth College, NH https://github.com/bx/elf-bf-tools @bxsays on twitter Definitions. "ELF" is an executable file format used in linking and loading executables (on UNIX/Linux-class machines). "Weird machine" uses undocumented computation sources (I think of them as unintended virtual machines). Some examples of "weird machines" are those that: return to weird location, does SQL injection, corrupts the heap. Bx then talked about using ELF metadata as (an uintended) "weird machine". Some ELF background: A compiler takes source code and generates a ELF object file (hello.o). A static linker makes an ELF executable from the object file. A runtime linker and loader takes ELF executable and loads and relocates it in memory. The ELF file has symbols to relocate functions and variables. ELF has two relocation tables—one at link time and another one at loading time: .rela.dyn (link time) and .dynsym (dynamic table). GOT: Global Offset Table of addresses for dynamically-linked functions. PLT: Procedure Linkage Tables—works with GOT. The memory layout of a process (not the ELF file) is, in order: program (+ heap), dynamic libraries, libc, ld.so, stack (which includes the dynamic table loaded into memory) For ELF, the "weird machine" is found and exploited in the loader. ELF can be crafted for executing viruses, by tricking runtime into executing interpreted "code" in the ELF symbol table. One can inject parasitic "code" without modifying the actual ELF code portions. Think of the ELF symbol table as an "assembly language" interpreter. It has these elements: instructions: Add, move, jump if not 0 (jnz) Think of symbol table entries as "registers" symbol table value is "contents" immediate values are constants direct values are addresses (e.g., 0xdeadbeef) move instruction: is a relocation table entry add instruction: relocation table "addend" entry jnz instruction: takes multiple relocation table entries The ELF weird machine exploits the loader by relocating relocation table entries. The loader will go on forever until told to stop. It stores state on stack at "end" and uses IFUNC table entries (containing function pointer address). The ELF weird machine, called "Brainfu*k" (BF) has: 8 instructions: pointer inc, dec, inc indirect, dec indirect, jump forward, jump backward, print. Three registers - 3 registers Bx showed example BF source code that implemented a Turing machine printing "hello, world". More interesting was the next demo, where bx modified ping. Ping runs suid as root, but quickly drops privilege. BF modified the loader to disable the library function call dropping privilege, so it remained as root. Then BF modified the ping -t argument to execute the -t filename as root. It's best to show what this modified ping does with an example: $ whoami bx $ ping localhost -t backdoor.sh # executes backdoor $ whoami root $ The modified code increased from 285948 bytes to 290209 bytes. A BF tool compiles "executable" by modifying the symbol table in an existing ELF executable. The tool modifies .dynsym and .rela.dyn table, but not code or data. Privacy at the Handset: New FCC Rules? "Valkyrie" (Christie Dudley, Santa Clara Law JD candidate) Valkyrie talked about mobile handset privacy. Some background: Senator Franken (also a comedian) became alarmed about CarrierIQ, where the carriers track their customers. Franken asked the FCC to find out what obligations carriers think they have to protect privacy. The carriers' response was that they are doing just fine with self-regulation—no worries! Carriers need to collect data, such as missed calls, to maintain network quality. But carriers also sell data for marketing. Verizon sells customer data and enables this with a narrow privacy policy (only 1 month to opt out, with difficulties). The data sold is not individually identifiable and is aggregated. But Verizon recommends, as an aggregation workaround to "recollate" data to other databases to identify customers indirectly. The FCC has regulated telephone privacy since 1934 and mobile network privacy since 2007. Also, the carriers say mobile phone privacy is a FTC responsibility (not FCC). FTC is trying to improve mobile app privacy, but FTC has no authority over carrier / customer relationships. As a side note, Apple iPhones are unique as carriers have extra control over iPhones they don't have with other smartphones. As a result iPhones may be more regulated. Who are the consumer advocates? Everyone knows EFF, but EPIC (Electrnic Privacy Info Center), although more obsecure, is more relevant. What to do? Carriers must be accountable. Opt-in and opt-out at any time. Carriers need incentive to grant users control for those who want it, by holding them liable and responsible for breeches on their clock. Location information should be added current CPNI privacy protection, and require "Pen/trap" judicial order to obtain (and would still be a lower standard than 4th Amendment). Politics are on a pro-privacy swing now, with many senators and the Whitehouse. There will probably be new regulation soon, and enforcement will be a problem, but consumers will still have some benefit. Hacking Measured Boot and UEFI Dan Griffin, JWSecure, Inc., Seattle, @JWSdan Dan talked about hacking measured UEFI boot. First some terms: UEFI is a boot technology that is replacing BIOS (has whitelisting and blacklisting). UEFI protects devices against rootkits. TPM - hardware security device to store hashs and hardware-protected keys "secure boot" can control at firmware level what boot images can boot "measured boot" OS feature that tracks hashes (from BIOS, boot loader, krnel, early drivers). "remote attestation" allows remote validation and control based on policy on a remote attestation server. Microsoft pushing TPM (Windows 8 required), but Google is not. Intel TianoCore is the only open source for UEFI. Dan has Measured Boot Tool at http://mbt.codeplex.com/ with a demo where you can also view TPM data. TPM support already on enterprise-class machines. UEFI Weaknesses. UEFI toolkits are evolving rapidly, but UEFI has weaknesses: assume user is an ally trust TPM implicitly, and attached to computer hibernate file is unprotected (disk encryption protects against this) protection migrating from hardware to firmware delays in patching and whitelist updates will UEFI really be adopted by the mainstream (smartphone hardware support, bank support, apathetic consumer support) You Can't Buy Security: Building the Open Source InfoSec Program Boris Sverdlik, ISDPodcast.com co-host Boris talked about problems typical with current security audits. "IT Security" is an oxymoron—IT exists to enable buiness, uptime, utilization, reporting, but don't care about security—IT has conflict of interest. There's no Magic Bullet ("blinky box"), no one-size-fits-all solution (e.g., Intrusion Detection Systems (IDSs)). Regulations don't make you secure. The cloud is not secure (because of shared data and admin access). Defense and pen testing is not sexy. Auditors are not solution (security not a checklist)—what's needed is experience and adaptability—need soft skills. Step 1: First thing is to Google and learn the company end-to-end before you start. Get to know the management team (not IT team), meet as many people as you can. Don't use arbitrary values such as CISSP scores. Quantitive risk assessment is a myth (e.g. AV*EF-SLE). Learn different Business Units, legal/regulatory obligations, learn the business and where the money is made, verify company is protected from script kiddies (easy), learn sensitive information (IP, internal use only), and start with low-hanging fruit (customer service reps and social engineering). Step 2: Policies. Keep policies short and relevant. Generic SANS "security" boilerplate policies don't make sense and are not followed. Focus on acceptable use, data usage, communications, physical security. Step 3: Implementation: keep it simple stupid. Open source, although useful, is not free (implementation cost). Access controls with authentication & authorization for local and remote access. MS Windows has it, otherwise use OpenLDAP, OpenIAM, etc. Application security Everyone tries to reinvent the wheel—use existing static analysis tools. Review high-risk apps and major revisions. Don't run different risk level apps on same system. Assume host/client compromised and use app-level security control. Network security VLAN != segregated because there's too many workarounds. Use explicit firwall rules, active and passive network monitoring (snort is free), disallow end user access to production environment, have a proxy instead of direct Internet access. Also, SSL certificates are not good two-factor auth and SSL does not mean "safe." Operational Controls Have change, patch, asset, & vulnerability management (OSSI is free). For change management, always review code before pushing to production For logging, have centralized security logging for business-critical systems, separate security logging from administrative/IT logging, and lock down log (as it has everything). Monitor with OSSIM (open source). Use intrusion detection, but not just to fulfill a checkbox: build rules from a whitelist perspective (snort). OSSEC has 95% of what you need. Vulnerability management is a QA function when done right: OpenVas and Seccubus are free. Security awareness The reality is users will always click everything. Build real awareness, not compliance driven checkbox, and have it integrated into the culture. Pen test by crowd sourcing—test with logging COSSP http://www.cossp.org/ - Comprehensive Open Source Security Project What Journalists Want: The Investigative Reporters' Perspective on Hacking Dave Maas, San Diego CityBeat Jason Leopold, Truthout.org The difference between hackers and investigative journalists: For hackers, the motivation varies, but method is same, technological specialties. For investigative journalists, it's about one thing—The Story, and they need broad info-gathering skills. J-School in 60 Seconds: Generic formula: Person or issue of pubic interest, new info, or angle. Generic criteria: proximity, prominence, timeliness, human interest, oddity, or consequence. Media awareness of hackers and trends: journalists becoming extremely aware of hackers with congressional debates (privacy, data breaches), demand for data-mining Journalists, use of coding and web development for Journalists, and Journalists busted for hacking (Murdock). Info gathering by investigative journalists include Public records laws. Federal Freedom of Information Act (FOIA) is good, but slow. California Public Records Act is a lot stronger. FOIA takes forever because of foot-dragging—it helps to be specific. Often need to sue (especially FBI). CPRA is faster, and requests can be vague. Dumps and leaks (a la Wikileaks) Journalists want: leads, protecting ourselves, our sources, and adapting tools for news gathering (Google hacking). Anonomity is important to whistleblowers. They want no digital footprint left behind (e.g., email, web log). They don't trust encryption, want to feel safe and secure. Whistleblower laws are very weak—there's no upside for whistleblowers—they have to be very passionate to do it. Accessibility and Security or: How I Learned to Stop Worrying and Love the Halting Problem Anna Shubina, Dartmouth College Anna talked about how accessibility and security are related. Accessibility of digital content (not real world accessibility). mostly refers to blind users and screenreaders, for our purpose. Accessibility is about parsing documents, as are many security issues. "Rich" executable content causes accessibility to fail, and often causes security to fail. For example MS Word has executable format—it's not a document exchange format—more dangerous than PDF or HTML. Accessibility is often the first and maybe only sanity check with parsing. They have no choice because someone may want to read what you write. Google, for example, is very particular about web browser you use and are bad at supporting other browsers. Uses JavaScript instead of links, often requiring mouseover to display content. PDF is a security nightmare. Executible format, embedded flash, JavaScript, etc. 15 million lines of code. Google Chrome doesn't handle PDF correctly, causing several security bugs. PDF has an accessibility checker and PDF tagging, to help with accessibility. But no PDF checker checks for incorrect tags, untagged content, or validates lists or tables. None check executable content at all. The "Halting Problem" is: can one decide whether a program will ever stop? The answer, in general, is no (Rice's theorem). The same holds true for accessibility checkers. Language-theoretic Security says complicated data formats are hard to parse and cannot be solved due to the Halting Problem. W3C Web Accessibility Guidelines: "Perceivable, Operable, Understandable, Robust" Not much help though, except for "Robust", but here's some gems: * all information should be parsable (paraphrasing) * if not parsable, cannot be converted to alternate formats * maximize compatibility in new document formats Executible webpages are bad for security and accessibility. They say it's for a better web experience. But is it necessary to stuff web pages with JavaScript for a better experience? A good example is The Drudge Report—it has hand-written HTML with no JavaScript, yet drives a lot of web traffic due to good content. A bad example is Google News—hidden scrollbars, guessing user input. Solutions: Accessibility and security problems come from same source Expose "better user experience" myth Keep your corner of Internet parsable Remember "Halting Problem"—recognize false solutions (checking and verifying tools) Stop Patching, for Stronger PCI Compliance Adam Brand, protiviti @adamrbrand, http://www.picfun.com/ Adam talked about PCI compliance for retail sales. Take an example: for PCI compliance, 50% of Brian's time (a IT guy), 960 hours/year was spent patching POSs in 850 restaurants. Often applying some patches make no sense (like fixing a browser vulnerability on a server). "Scanner worship" is overuse of vulnerability scanners—it gives a warm and fuzzy and it's simple (red or green results—fix reds). Scanners give a false sense of security. In reality, breeches from missing patches are uncommon—more common problems are: default passwords, cleartext authentication, misconfiguration (firewall ports open). Patching Myths: Myth 1: install within 30 days of patch release (but PCI §6.1 allows a "risk-based approach" instead). Myth 2: vendor decides what's critical (also PCI §6.1). But §6.2 requires user ranking of vulnerabilities instead. Myth 3: scan and rescan until it passes. But PCI §11.2.1b says this applies only to high-risk vulnerabilities. Adam says good recommendations come from NIST 800-40. Instead use sane patching and focus on what's really important. From NIST 800-40: Proactive: Use a proactive vulnerability management process: use change control, configuration management, monitor file integrity. Monitor: start with NVD and other vulnerability alerts, not scanner results. Evaluate: public-facing system? workstation? internal server? (risk rank) Decide:on action and timeline Test: pre-test patches (stability, functionality, rollback) for change control Install: notify, change control, tickets McAfee Secure & Trustmarks — a Hacker's Best Friend Jay James, Shane MacDougall, Tactical Intelligence Inc., Canada "McAfee Secure Trustmark" is a website seal marketed by McAfee. A website gets this badge if they pass their remote scanning. The problem is a removal of trustmarks act as flags that you're vulnerable. Easy to view status change by viewing McAfee list on website or on Google. "Secure TrustGuard" is similar to McAfee. Jay and Shane wrote Perl scripts to gather sites from McAfee and search engines. If their certification image changes to a 1x1 pixel image, then they are longer certified. Their scripts take deltas of scans to see what changed daily. The bottom line is change in TrustGuard status is a flag for hackers to attack your site. Entire idea of seals is silly—you're raising a flag saying if you're vulnerable.

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• Toorcon 15 (2013)

  - by danx

  The Toorcon gang (senior staff): h1kari (founder), nfiltr8, and Geo Introduction to Toorcon 15 (2013) A Tale of One Software Bypass of MS Windows 8 Secure Boot Breaching SSL, One Byte at a Time Running at 99%: Surviving an Application DoS Security Response in the Age of Mass Customized Attacks x86 Rewriting: Defeating RoP and other Shinanighans Clowntown Express: interesting bugs and running a bug bounty program Active Fingerprinting of Encrypted VPNs Making Attacks Go Backwards Mask Your Checksums—The Gorry Details Adventures with weird machines thirty years after "Reflections on Trusting Trust" Introduction to Toorcon 15 (2013) Toorcon 15 is the 15th annual security conference held in San Diego. I've attended about a third of them and blogged about previous conferences I attended here starting in 2003. As always, I've only summarized the talks I attended and interested me enough to write about them. Be aware that I may have misrepresented the speaker's remarks and that they are not my remarks or opinion, or those of my employer, so don't quote me or them. Those seeking further details may contact the speakers directly or use The Google. For some talks, I have a URL for further information. A Tale of One Software Bypass of MS Windows 8 Secure Boot Andrew Furtak and Oleksandr Bazhaniuk Yuri Bulygin, Oleksandr ("Alex") Bazhaniuk, and (not present) Andrew Furtak Yuri and Alex talked about UEFI and Bootkits and bypassing MS Windows 8 Secure Boot, with vendor recommendations. They previously gave this talk at the BlackHat 2013 conference. MS Windows 8 Secure Boot Overview UEFI (Unified Extensible Firmware Interface) is interface between hardware and OS. UEFI is processor and architecture independent. Malware can replace bootloader (bootx64.efi, bootmgfw.efi). Once replaced can modify kernel. Trivial to replace bootloader. Today many legacy bootkits—UEFI replaces them most of them. MS Windows 8 Secure Boot verifies everything you load, either through signatures or hashes. UEFI firmware relies on secure update (with signed update). You would think Secure Boot would rely on ROM (such as used for phones0, but you can't do that for PCs—PCs use writable memory with signatures DXE core verifies the UEFI boat loader(s) OS Loader (winload.efi, winresume.efi) verifies the OS kernel A chain of trust is established with a root key (Platform Key, PK), which is a cert belonging to the platform vendor. Key Exchange Keys (KEKs) verify an "authorized" database (db), and "forbidden" database (dbx). X.509 certs with SHA-1/SHA-256 hashes. Keys are stored in non-volatile (NV) flash-based NVRAM. Boot Services (BS) allow adding/deleting keys (can't be accessed once OS starts—which uses Run-Time (RT)). Root cert uses RSA-2048 public keys and PKCS#7 format signatures. SecureBoot — enable disable image signature checks SetupMode — update keys, self-signed keys, and secure boot variables CustomMode — allows updating keys Secure Boot policy settings are: always execute, never execute, allow execute on security violation, defer execute on security violation, deny execute on security violation, query user on security violation Attacking MS Windows 8 Secure Boot Secure Boot does NOT protect from physical access. Can disable from console. Each BIOS vendor implements Secure Boot differently. There are several platform and BIOS vendors. It becomes a "zoo" of implementations—which can be taken advantage of. Secure Boot is secure only when all vendors implement it correctly. Allow only UEFI firmware signed updates protect UEFI firmware from direct modification in flash memory protect FW update components program SPI controller securely protect secure boot policy settings in nvram protect runtime api disable compatibility support module which allows unsigned legacy Can corrupt the Platform Key (PK) EFI root certificate variable in SPI flash. If PK is not found, FW enters setup mode wich secure boot turned off. Can also exploit TPM in a similar manner. One is not supposed to be able to directly modify the PK in SPI flash from the OS though. But they found a bug that they can exploit from User Mode (undisclosed) and demoed the exploit. It loaded and ran their own bootkit. The exploit requires a reboot. Multiple vendors are vulnerable. They will disclose this exploit to vendors in the future. Recommendations: allow only signed updates protect UEFI fw in ROM protect EFI variable store in ROM Breaching SSL, One Byte at a Time Yoel Gluck and Angelo Prado Angelo Prado and Yoel Gluck, Salesforce.com CRIME is software that performs a "compression oracle attack." This is possible because the SSL protocol doesn't hide length, and because SSL compresses the header. CRIME requests with every possible character and measures the ciphertext length. Look for the plaintext which compresses the most and looks for the cookie one byte-at-a-time. SSL Compression uses LZ77 to reduce redundancy. Huffman coding replaces common byte sequences with shorter codes. US CERT thinks the SSL compression problem is fixed, but it isn't. They convinced CERT that it wasn't fixed and they issued a CVE. BREACH, breachattrack.com BREACH exploits the SSL response body (Accept-Encoding response, Content-Encoding). It takes advantage of the fact that the response is not compressed. BREACH uses gzip and needs fairly "stable" pages that are static for ~30 seconds. It needs attacker-supplied content (say from a web form or added to a URL parameter). BREACH listens to a session's requests and responses, then inserts extra requests and responses. Eventually, BREACH guesses a session's secret key. Can use compression to guess contents one byte at-a-time. For example, "Supersecret SupersecreX" (a wrong guess) compresses 10 bytes, and "Supersecret Supersecret" (a correct guess) compresses 11 bytes, so it can find each character by guessing every character. To start the guess, BREACH needs at least three known initial characters in the response sequence. Compression length then "leaks" information. Some roadblocks include no winners (all guesses wrong) or too many winners (multiple possibilities that compress the same). The solutions include: lookahead (guess 2 or 3 characters at-a-time instead of 1 character). Expensive rollback to last known conflict check compression ratio can brute-force first 3 "bootstrap" characters, if needed (expensive) block ciphers hide exact plain text length. Solution is to align response in advance to block size Mitigations length: use variable padding secrets: dynamic CSRF tokens per request secret: change over time separate secret to input-less servlets Future work eiter understand DEFLATE/GZIP HTTPS extensions Running at 99%: Surviving an Application DoS Ryan Huber Ryan Huber, Risk I/O Ryan first discussed various ways to do a denial of service (DoS) attack against web services. One usual method is to find a slow web page and do several wgets. Or download large files. Apache is not well suited at handling a large number of connections, but one can put something in front of it Can use Apache alternatives, such as nginx How to identify malicious hosts short, sudden web requests user-agent is obvious (curl, python) same url requested repeatedly no web page referer (not normal) hidden links. hide a link and see if a bot gets it restricted access if not your geo IP (unless the website is global) missing common headers in request regular timing first seen IP at beginning of attack count requests per hosts (usually a very large number) Use of captcha can mitigate attacks, but you'll lose a lot of genuine users. Bouncer, goo.gl/c2vyEc and www.github.com/rawdigits/Bouncer Bouncer is software written by Ryan in netflow. Bouncer has a small, unobtrusive footprint and detects DoS attempts. It closes blacklisted sockets immediately (not nice about it, no proper close connection). Aggregator collects requests and controls your web proxies. Need NTP on the front end web servers for clean data for use by bouncer. Bouncer is also useful for a popularity storm ("Slashdotting") and scraper storms. Future features: gzip collection data, documentation, consumer library, multitask, logging destroyed connections. Takeaways: DoS mitigation is easier with a complete picture Bouncer designed to make it easier to detect and defend DoS—not a complete cure Security Response in the Age of Mass Customized Attacks Peleus Uhley and Karthik Raman Peleus Uhley and Karthik Raman, Adobe ASSET, blogs.adobe.com/asset/ Peleus and Karthik talked about response to mass-customized exploits. Attackers behave much like a business. "Mass customization" refers to concept discussed in the book Future Perfect by Stan Davis of Harvard Business School. Mass customization is differentiating a product for an individual customer, but at a mass production price. For example, the same individual with a debit card receives basically the same customized ATM experience around the world. Or designing your own PC from commodity parts. Exploit kits are another example of mass customization. The kits support multiple browsers and plugins, allows new modules. Exploit kits are cheap and customizable. Organized gangs use exploit kits. A group at Berkeley looked at 77,000 malicious websites (Grier et al., "Manufacturing Compromise: The Emergence of Exploit-as-a-Service", 2012). They found 10,000 distinct binaries among them, but derived from only a dozen or so exploit kits. Characteristics of Mass Malware: potent, resilient, relatively low cost Technical characteristics: multiple OS, multipe payloads, multiple scenarios, multiple languages, obfuscation Response time for 0-day exploits has gone down from ~40 days 5 years ago to about ~10 days now. So the drive with malware is towards mass customized exploits, to avoid detection There's plenty of evicence that exploit development has Project Manager bureaucracy. They infer from the malware edicts to: support all versions of reader support all versions of windows support all versions of flash support all browsers write large complex, difficult to main code (8750 lines of JavaScript for example Exploits have "loose coupling" of multipe versions of software (adobe), OS, and browser. This allows specific attacks against specific versions of multiple pieces of software. Also allows exploits of more obscure software/OS/browsers and obscure versions. Gave examples of exploits that exploited 2, 3, 6, or 14 separate bugs. However, these complete exploits are more likely to be buggy or fragile in themselves and easier to defeat. Future research includes normalizing malware and Javascript. Conclusion: The coming trend is that mass-malware with mass zero-day attacks will result in mass customization of attacks. x86 Rewriting: Defeating RoP and other Shinanighans Richard Wartell Richard Wartell The attack vector we are addressing here is: First some malware causes a buffer overflow. The malware has no program access, but input access and buffer overflow code onto stack Later the stack became non-executable. The workaround malware used was to write a bogus return address to the stack jumping to malware Later came ASLR (Address Space Layout Randomization) to randomize memory layout and make addresses non-deterministic. The workaround malware used was to jump t existing code segments in the program that can be used in bad ways "RoP" is Return-oriented Programming attacks. RoP attacks use your own code and write return address on stack to (existing) expoitable code found in program ("gadgets"). Pinkie Pie was paid $60K last year for a RoP attack. One solution is using anti-RoP compilers that compile source code with NO return instructions. ASLR does not randomize address space, just "gadgets". IPR/ILR ("Instruction Location Randomization") randomizes each instruction with a virtual machine. Richard's goal was to randomize a binary with no source code access. He created "STIR" (Self-Transofrming Instruction Relocation). STIR disassembles binary and operates on "basic blocks" of code. The STIR disassembler is conservative in what to disassemble. Each basic block is moved to a random location in memory. Next, STIR writes new code sections with copies of "basic blocks" of code in randomized locations. The old code is copied and rewritten with jumps to new code. the original code sections in the file is marked non-executible. STIR has better entropy than ASLR in location of code. Makes brute force attacks much harder. STIR runs on MS Windows (PEM) and Linux (ELF). It eliminated 99.96% or more "gadgets" (i.e., moved the address). Overhead usually 5-10% on MS Windows, about 1.5-4% on Linux (but some code actually runs faster!). The unique thing about STIR is it requires no source access and the modified binary fully works! Current work is to rewrite code to enforce security policies. For example, don't create a *.{exe,msi,bat} file. Or don't connect to the network after reading from the disk. Clowntown Express: interesting bugs and running a bug bounty program Collin Greene Collin Greene, Facebook Collin talked about Facebook's bug bounty program. Background at FB: FB has good security frameworks, such as security teams, external audits, and cc'ing on diffs. But there's lots of "deep, dark, forgotten" parts of legacy FB code. Collin gave several examples of bountied bugs. Some bounty submissions were on software purchased from a third-party (but bounty claimers don't know and don't care). We use security questions, as does everyone else, but they are basically insecure (often easily discoverable). Collin didn't expect many bugs from the bounty program, but they ended getting 20+ good bugs in first 24 hours and good submissions continue to come in. Bug bounties bring people in with different perspectives, and are paid only for success. Bug bounty is a better use of a fixed amount of time and money versus just code review or static code analysis. The Bounty program started July 2011 and paid out $1.5 million to date. 14% of the submissions have been high priority problems that needed to be fixed immediately. The best bugs come from a small % of submitters (as with everything else)—the top paid submitters are paid 6 figures a year. Spammers like to backstab competitors. The youngest sumitter was 13. Some submitters have been hired. Bug bounties also allows to see bugs that were missed by tools or reviews, allowing improvement in the process. Bug bounties might not work for traditional software companies where the product has release cycle or is not on Internet. Active Fingerprinting of Encrypted VPNs Anna Shubina Anna Shubina, Dartmouth Institute for Security, Technology, and Society (I missed the start of her talk because another track went overtime. But I have the DVD of the talk, so I'll expand later) IPsec leaves fingerprints. Using netcat, one can easily visually distinguish various crypto chaining modes just from packet timing on a chart (example, DES-CBC versus AES-CBC) One can tell a lot about VPNs just from ping roundtrips (such as what router is used) Delayed packets are not informative about a network, especially if far away from the network More needed to explore about how TCP works in real life with respect to timing Making Attacks Go Backwards Fuzzynop FuzzyNop, Mandiant This talk is not about threat attribution (finding who), product solutions, politics, or sales pitches. But who are making these malware threats? It's not a single person or group—they have diverse skill levels. There's a lot of fat-fingered fumblers out there. Always look for low-hanging fruit first: "hiding" malware in the temp, recycle, or root directories creation of unnamed scheduled tasks obvious names of files and syscalls ("ClearEventLog") uncleared event logs. Clearing event log in itself, and time of clearing, is a red flag and good first clue to look for on a suspect system Reverse engineering is hard. Disassembler use takes practice and skill. A popular tool is IDA Pro, but it takes multiple interactive iterations to get a clean disassembly. Key loggers are used a lot in targeted attacks. They are typically custom code or built in a backdoor. A big tip-off is that non-printable characters need to be printed out (such as "[Ctrl]" "[RightShift]") or time stamp printf strings. Look for these in files. Presence is not proof they are used. Absence is not proof they are not used. Java exploits. Can parse jar file with idxparser.py and decomile Java file. Java typially used to target tech companies. Backdoors are the main persistence mechanism (provided externally) for malware. Also malware typically needs command and control. Application of Artificial Intelligence in Ad-Hoc Static Code Analysis John Ashaman John Ashaman, Security Innovation Initially John tried to analyze open source files with open source static analysis tools, but these showed thousands of false positives. Also tried using grep, but tis fails to find anything even mildly complex. So next John decided to write his own tool. His approach was to first generate a call graph then analyze the graph. However, the problem is that making a call graph is really hard. For example, one problem is "evil" coding techniques, such as passing function pointer. First the tool generated an Abstract Syntax Tree (AST) with the nodes created from method declarations and edges created from method use. Then the tool generated a control flow graph with the goal to find a path through the AST (a maze) from source to sink. The algorithm is to look at adjacent nodes to see if any are "scary" (a vulnerability), using heuristics for search order. The tool, called "Scat" (Static Code Analysis Tool), currently looks for C# vulnerabilities and some simple PHP. Later, he plans to add more PHP, then JSP and Java. For more information see his posts in Security Innovation blog and NRefactory on GitHub. Mask Your Checksums—The Gorry Details Eric (XlogicX) Davisson Eric (XlogicX) Davisson Sometimes in emailing or posting TCP/IP packets to analyze problems, you may want to mask the IP address. But to do this correctly, you need to mask the checksum too, or you'll leak information about the IP. Problem reports found in stackoverflow.com, sans.org, and pastebin.org are usually not masked, but a few companies do care. If only the IP is masked, the IP may be guessed from checksum (that is, it leaks data). Other parts of packet may leak more data about the IP. TCP and IP checksums both refer to the same data, so can get more bits of information out of using both checksums than just using one checksum. Also, one can usually determine the OS from the TTL field and ports in a packet header. If we get hundreds of possible results (16x each masked nibble that is unknown), one can do other things to narrow the results, such as look at packet contents for domain or geo information. With hundreds of results, can import as CSV format into a spreadsheet. Can corelate with geo data and see where each possibility is located. Eric then demoed a real email report with a masked IP packet attached. Was able to find the exact IP address, given the geo and university of the sender. Point is if you're going to mask a packet, do it right. Eric wouldn't usually bother, but do it correctly if at all, to not create a false impression of security. Adventures with weird machines thirty years after "Reflections on Trusting Trust" Sergey Bratus Sergey Bratus, Dartmouth College (and Julian Bangert and Rebecca Shapiro, not present) "Reflections on Trusting Trust" refers to Ken Thompson's classic 1984 paper. "You can't trust code that you did not totally create yourself." There's invisible links in the chain-of-trust, such as "well-installed microcode bugs" or in the compiler, and other planted bugs. Thompson showed how a compiler can introduce and propagate bugs in unmodified source. But suppose if there's no bugs and you trust the author, can you trust the code? Hell No! There's too many factors—it's Babylonian in nature. Why not? Well, Input is not well-defined/recognized (code's assumptions about "checked" input will be violated (bug/vunerabiliy). For example, HTML is recursive, but Regex checking is not recursive. Input well-formed but so complex there's no telling what it does For example, ELF file parsing is complex and has multiple ways of parsing. Input is seen differently by different pieces of program or toolchain Any Input is a program input executes on input handlers (drives state changes & transitions) only a well-defined execution model can be trusted (regex/DFA, PDA, CFG) Input handler either is a "recognizer" for the inputs as a well-defined language (see langsec.org) or it's a "virtual machine" for inputs to drive into pwn-age ELF ABI (UNIX/Linux executible file format) case study. Problems can arise from these steps (without planting bugs): compiler linker loader ld.so/rtld relocator DWARF (debugger info) exceptions The problem is you can't really automatically analyze code (it's the "halting problem" and undecidable). Only solution is to freeze code and sign it. But you can't freeze everything! Can't freeze ASLR or loading—must have tables and metadata. Any sufficiently complex input data is the same as VM byte code Example, ELF relocation entries + dynamic symbols == a Turing Complete Machine (TM). @bxsays created a Turing machine in Linux from relocation data (not code) in an ELF file. For more information, see Rebecca "bx" Shapiro's presentation from last year's Toorcon, "Programming Weird Machines with ELF Metadata" @bxsays did same thing with Mach-O bytecode Or a DWARF exception handling data .eh_frame + glibc == Turning Machine X86 MMU (IDT, GDT, TSS): used address translation to create a Turning Machine. Page handler reads and writes (on page fault) memory. Uses a page table, which can be used as Turning Machine byte code. Example on Github using this TM that will fly a glider across the screen Next Sergey talked about "Parser Differentials". That having one input format, but two parsers, will create confusion and opportunity for exploitation. For example, CSRs are parsed during creation by cert requestor and again by another parser at the CA. Another example is ELF—several parsers in OS tool chain, which are all different. Can have two different Program Headers (PHDRs) because ld.so parses multiple PHDRs. The second PHDR can completely transform the executable. This is described in paper in the first issue of International Journal of PoC. Conclusions trusting computers not only about bugs! Bugs are part of a problem, but no by far all of it complex data formats means bugs no "chain of trust" in Babylon! (that is, with parser differentials) we need to squeeze complexity out of data until data stops being "code equivalent" Further information See and langsec.org. USENIX WOOT 2013 (Workshop on Offensive Technologies) for "weird machines" papers and videos.

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• Extending NerdDinner: Adding Geolocated Flair

  - by Jon Galloway

  NerdDinner is a website with the audacious goal of “Organizing the world’s nerds and helping them eat in packs.” Because nerds aren’t likely to socialize with others unless a website tells them to do it. Scott Hanselman showed off a lot of the cool features we’ve added to NerdDinner lately during his popular talk at MIX10, Beyond File | New Company: From Cheesy Sample to Social Platform. Did you miss it? Go ahead and watch it, I’ll wait. One of the features we wanted to add was flair. You know about flair, right? It’s a way to let folks who like your site show it off in their own site. For example, here’s my StackOverflow flair: Great! So how could we add some of this flair stuff to NerdDinner? What do we want to show? If we’re going to encourage our users to give up a bit of their beautiful website to show off a bit of ours, we need to think about what they’ll want to show. For instance, my StackOverflow flair is all about me, not StackOverflow. So how will this apply to NerdDinner? Since NerdDinner is all about organizing local dinners, in order for the flair to be useful it needs to make sense for the person viewing the web page. If someone visits from Egypt visits my blog, they should see information about NerdDinners in Egypt. That’s geolocation – localizing site content based on where the browser’s sitting, and it makes sense for flair as well as entire websites. So we’ll set up a simple little callout that prompts them to host a dinner in their area: Hopefully our flair works and there is a dinner near your viewers, so they’ll see another view which lists upcoming dinners near them: The Geolocation Part Generally website geolocation is done by mapping the requestor’s IP address to a geographic area. It’s not an exact science, but I’ve always found it to be pretty accurate. There are (at least) three ways to handle it: You pay somebody like MaxMind for a database (with regular updates) that sits on your server, and you use their API to do lookups. I used this on a pretty big project a few years ago and it worked well. You use HTML 5 Geolocation API or Google Gears or some other browser based solution. I think those are cool (I use Google Gears a lot), but they’re both in flux right now and I don’t think either has a wide enough of an install base yet to rely on them. You might want to, but I’ve heard you do all kinds of crazy stuff, and sometimes it gets you in trouble. I don’t mean talk out of line, but we all laugh behind your back a bit. But, hey, it’s up to you. It’s your flair or whatever. There are some free webservices out there that will take an IP address and give you location information. Easy, and works for everyone. That’s what we’re doing. I looked at a few different services and settled on IPInfoDB. It’s free, has a great API, and even returns JSON, which is handy for Javascript use. The IP query is pretty simple. We hit a URL like this: http://ipinfodb.com/ip_query.php?ip=74.125.45.100&timezone=false … and we get an XML response back like this… <?xml version="1.0" encoding="UTF-8"?> <Response> <Ip>74.125.45.100</Ip> <Status>OK</Status> <CountryCode>US</CountryCode> <CountryName>United States</CountryName> <RegionCode>06</RegionCode> <RegionName>California</RegionName> <City>Mountain View</City> <ZipPostalCode>94043</ZipPostalCode> <Latitude>37.4192</Latitude> <Longitude>-122.057</Longitude> </Response> So we’ll build some data transfer classes to hold the location information, like this: public class LocationInfo { public string Country { get; set; } public string RegionName { get; set; } public string City { get; set; } public string ZipPostalCode { get; set; } public LatLong Position { get; set; } } public class LatLong { public float Lat { get; set; } public float Long { get; set; } } And now hitting the service is pretty simple: public static LocationInfo HostIpToPlaceName(string ip) { string url = "http://ipinfodb.com/ip_query.php?ip={0}&timezone=false"; url = String.Format(url, ip); var result = XDocument.Load(url); var location = (from x in result.Descendants("Response") select new LocationInfo { City = (string)x.Element("City"), RegionName = (string)x.Element("RegionName"), Country = (string)x.Element("CountryName"), ZipPostalCode = (string)x.Element("CountryName"), Position = new LatLong { Lat = (float)x.Element("Latitude"), Long = (float)x.Element("Longitude") } }).First(); return location; } Getting The User’s IP Okay, but first we need the end user’s IP, and you’d think it would be as simple as reading the value from HttpContext: HttpContext.Current.Request.UserHostAddress But you’d be wrong. Sorry. UserHostAddress just wraps HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"], but that doesn’t get you the IP for users behind a proxy. That’s in another header, “HTTP_X_FORWARDED_FOR". So you can either hit a wrapper and then check a header, or just check two headers. I went for uniformity: string SourceIP = string.IsNullOrEmpty(Request.ServerVariables["HTTP_X_FORWARDED_FOR"]) ? Request.ServerVariables["REMOTE_ADDR"] : Request.ServerVariables["HTTP_X_FORWARDED_FOR"]; We’re almost set to wrap this up, but first let’s talk about our views. Yes, views, because we’ll have two. Selecting the View We wanted to make it easy for people to include the flair in their sites, so we looked around at how other people were doing this. The StackOverflow folks have a pretty good flair system, which allows you to include the flair in your site as either an IFRAME reference or a Javascript include. We’ll do both. We have a ServicesController to handle use of the site information outside of NerdDinner.com, so this fits in pretty well there. We’ll be displaying the same information for both HTML and Javascript flair, so we can use one Flair controller action which will return a different view depending on the requested format. Here’s our general flow for our controller action: Get the user’s IP Translate it to a location Grab the top three upcoming dinners that are near that location Select the view based on the format (defaulted to “html”) Return a FlairViewModel which contains the list of dinners and the location information public ActionResult Flair(string format = "html") { string SourceIP = string.IsNullOrEmpty( Request.ServerVariables["HTTP_X_FORWARDED_FOR"]) ? Request.ServerVariables["REMOTE_ADDR"] : Request.ServerVariables["HTTP_X_FORWARDED_FOR"]; var location = GeolocationService.HostIpToPlaceName(SourceIP); var dinners = dinnerRepository. FindByLocation(location.Position.Lat, location.Position.Long). OrderByDescending(p => p.EventDate).Take(3); // Select the view we'll return. // Using a switch because we'll add in JSON and other formats later. string view; switch (format.ToLower()) { case "javascript": view = "JavascriptFlair"; break; default: view = "Flair"; break; } return View( view, new FlairViewModel { Dinners = dinners.ToList(), LocationName = string.IsNullOrEmpty(location.City) ? "you" : String.Format("{0}, {1}", location.City, location.RegionName) } ); } Note: I’m not in love with the logic here, but it seems like overkill to extract the switch statement away when we’ll probably just have two or three views. What do you think? The HTML View The HTML version of the view is pretty simple – the only thing of any real interest here is the use of an extension method to truncate strings that are would cause the titles to wrap. public static string Truncate(this string s, int maxLength) { if (string.IsNullOrEmpty(s) || maxLength <= 0) return string.Empty; else if (s.Length > maxLength) return s.Substring(0, maxLength) + "..."; else return s; }   So here’s how the HTML view ends up looking: <%@ Page Title="" Language="C#" Inherits="System.Web.Mvc.ViewPage<FlairViewModel>" %> <%@ Import Namespace="NerdDinner.Helpers" %> <%@ Import Namespace="NerdDinner.Models" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Nerd Dinner</title> <link href="/Content/Flair.css" rel="stylesheet" type="text/css" /> </head> <body> <div id="nd-wrapper"> <h2 id="nd-header">NerdDinner.com</h2> <div id="nd-outer"> <% if (Model.Dinners.Count == 0) { %> <div id="nd-bummer"> Looks like there's no Nerd Dinners near <%:Model.LocationName %> in the near future. Why not <a target="_blank" href="http://www.nerddinner.com/Dinners/Create">host one</a>?</div> <% } else { %> <h3> Dinners Near You</h3> <ul> <% foreach (var item in Model.Dinners) { %> <li> <%: Html.ActionLink(String.Format("{0} with {1} on {2}", item.Title.Truncate(20), item.HostedBy, item.EventDate.ToShortDateString()), "Details", "Dinners", new { id = item.DinnerID }, new { target = "_blank" })%></li> <% } %> </ul> <% } %> <div id="nd-footer"> More dinners and fun at <a target="_blank" href="http://nrddnr.com">http://nrddnr.com</a></div> </div> </div> </body> </html> You’d include this in a page using an IFRAME, like this: <IFRAME height=230 marginHeight=0 src="http://nerddinner.com/services/flair" frameBorder=0 width=160 marginWidth=0 scrolling=no></IFRAME> The Javascript view The Javascript flair is written so you can include it in a webpage with a simple script include, like this: <script type="text/javascript" src="http://nerddinner.com/services/flair?format=javascript"></script> The goal of this view is very similar to the HTML embed view, with a few exceptions: We’re creating a script element and adding it to the head of the document, which will then document.write out the content. Note that you have to consider if your users will actually have a <head> element in their documents, but for website flair use cases I think that’s a safe bet. Since the content is being added to the existing page rather than shown in an IFRAME, all links need to be absolute. That means we can’t use Html.ActionLink, since it generates relative routes. We need to escape everything since it’s being written out as strings. We need to set the content type to application/x-javascript. The easiest way to do that is to use the <%@ Page ContentType%> directive. <%@ Page Language="C#" Inherits="System.Web.Mvc.ViewPage<NerdDinner.Models.FlairViewModel>" ContentType="application/x-javascript" %> <%@ Import Namespace="NerdDinner.Helpers" %> <%@ Import Namespace="NerdDinner.Models" %> document.write('<script>var link = document.createElement(\"link\");link.href = \"http://nerddinner.com/content/Flair.css\";link.rel = \"stylesheet\";link.type = \"text/css\";var head = document.getElementsByTagName(\"head\")[0];head.appendChild(link);</script>'); document.write('<div id=\"nd-wrapper\"><h2 id=\"nd-header\">NerdDinner.com</h2><div id=\"nd-outer\">'); <% if (Model.Dinners.Count == 0) { %> document.write('<div id=\"nd-bummer\">Looks like there\'s no Nerd Dinners near <%:Model.LocationName %> in the near future. Why not <a target=\"_blank\" href=\"http://www.nerddinner.com/Dinners/Create\">host one</a>?</div>'); <% } else { %> document.write('<h3> Dinners Near You</h3><ul>'); <% foreach (var item in Model.Dinners) { %> document.write('<li><a target=\"_blank\" href=\"http://nrddnr.com/<%: item.DinnerID %>\"><%: item.Title.Truncate(20) %> with <%: item.HostedBy %> on <%: item.EventDate.ToShortDateString() %></a></li>'); <% } %> document.write('</ul>'); <% } %> document.write('<div id=\"nd-footer\"> More dinners and fun at <a target=\"_blank\" href=\"http://nrddnr.com\">http://nrddnr.com</a></div></div></div>'); Getting IP’s for Testing There are a variety of online services that will translate a location to an IP, which were handy for testing these out. I found http://www.itouchmap.com/latlong.html to be most useful, but I’m open to suggestions if you know of something better. Next steps I think the next step here is to minimize load – you know, in case people start actually using this flair. There are two places to think about – the NerdDinner.com servers, and the services we’re using for Geolocation. I usually think about caching as a first attack on server load, but that’s less helpful here since every user will have a different IP. Instead, I’d look at taking advantage of Asynchronous Controller Actions, a cool new feature in ASP.NET MVC 2. Async Actions let you call a potentially long-running webservice without tying up a thread on the server while waiting for the response. There’s some good info on that in the MSDN documentation, and Dino Esposito wrote a great article on Asynchronous ASP.NET Pages in the April 2010 issue of MSDN Magazine. But let’s think of the children, shall we? What about ipinfodb.com? Well, they don’t have specific daily limits, but they do throttle you if you put a lot of traffic on them. From their FAQ: We do not have a specific daily limit but queries that are at a rate faster than 2 per second will be put in "queue". If you stay below 2 queries/second everything will be normal. If you go over the limit, you will still get an answer for all queries but they will be slowed down to about 1 per second. This should not affect most users but for high volume websites, you can either use our IP database on your server or we can whitelist your IP for 5$/month (simply use the donate form and leave a comment with your server IP). Good programming practices such as not querying our API for all page views (you can store the data in a cookie or a database) will also help not reaching the limit. So the first step there is to save the geolocalization information in a time-limited cookie, which will allow us to look up the local dinners immediately without having to hit the geolocation service.

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• Red Gate Coder interviews: Robin Hellen

  - by Michael Williamson

  Robin Hellen is a test engineer here at Red Gate, and is also the latest coder I’ve interviewed. We chatted about debugging code, the roles of software engineers and testers, and why Vala is currently his favourite programming language. How did you get started with programming?It started when I was about six. My dad’s a professional programmer, and he gave me and my sister one of his old computers and taught us a bit about programming. It was an old Amiga 500 with a variant of BASIC. I don’t think I ever successfully completed anything! It was just faffing around. I didn’t really get anywhere with it.But then presumably you did get somewhere with it at some point.At some point. The PC emerged as the dominant platform, and I learnt a bit of Visual Basic. I didn’t really do much, just a couple of quick hacky things. A bit of demo animation. Took me a long time to get anywhere with programming, really.When did you feel like you did start to get somewhere?I think it was when I started doing things for someone else, which was my sister’s final year of university project. She called up my dad two days before she was due to submit, saying “We need something to display a graph!”. Dad says, “I’m too busy, go talk to your brother”. So I hacked up this ugly piece of code, sent it off and they won a prize for that project. Apparently, the graph, the bit that I wrote, was the reason they won a prize! That was when I first felt that I’d actually done something that was worthwhile. That was my first real bit of code, and the ugliest code I’ve ever written. It’s basically an array of pre-drawn line elements that I shifted round the screen to draw a very spikey graph.When did you decide that programming might actually be something that you wanted to do as a career?It’s not really a decision I took, I always wanted to do something with computers. And I had to take a gap year for uni, so I was looking for twelve month internships. I applied to Red Gate, and they gave me a job as a tester. And that’s where I really started having to write code well. To a better standard that I had been up to that point.How did you find coming to Red Gate and working with other coders?I thought it was really nice. I learnt so much just from other people around. I think one of the things that’s really great is that people are just willing to help you learn. Instead of “Don’t you know that, you’re so stupid”, it’s “You can just do it this way”.If you could go back to the very start of that internship, is there something that you would tell yourself?Write shorter code. I have a tendency to write massive, many-thousand line files that I break out of right at the end. And then half-way through a project I’m doing something, I think “Where did I write that bit that does that thing?”, and it’s almost impossible to find. I wrote some horrendous code when I started. Just that principle, just keep things short. Even if looks a bit crazy to be jumping around all over the place all of the time, it’s actually a lot more understandable.And how do you hold yourself to that?Generally, if a function’s going off my screen, it’s probably too long. That’s what I tell myself, and within the team here we have code reviews, so the guys I’m with at the moment are pretty good at pulling me up on, “Doesn’t that look like it’s getting a bit long?”. It’s more just the subjective standard of readability than anything.So you’re an advocate of code review?Yes, definitely. Both to spot errors that you might have made, and to improve your knowledge. The person you’re reviewing will say “Oh, you could have done it that way”. That’s how we learn, by talking to others, and also just sharing knowledge of how your project works around the team, or even outside the team. Definitely a very firm advocate of code reviews.Do you think there’s more we could do with them?I don’t know. We’re struggling with how to add them as part of the process without it becoming too cumbersome. We’ve experimented with a few different ways, and we’ve not found anything that just works.To get more into the nitty gritty: how do you like to debug code?The first thing is to do it in my head. I’ll actually think what piece of code is likely to have caused that error, and take a quick look at it, just to see if there’s anything glaringly obvious there. The next thing I’ll probably do is throw in print statements, or throw some exceptions from various points, just to check: is it going through the code path I expect it to? A last resort is to actually debug code using a debugger.Why is the debugger the last resort?Probably because of the environments I learnt programming in. VB and early BASIC didn’t have much of a debugger, the only way to find out what your program was doing was to add print statements. Also, because a lot of the stuff I tend to work with is non-interactive, if it’s something that takes a long time to run, I can throw in the print statements, set a run off, go and do something else, and look at it again later, rather than trying to remember what happened at that point when I was debugging through it. So it also gives me the record of what happens. I hate just sitting there pressing F5, F5, continually. If you’re having to find out what your code is doing at each line, you’ve probably got a very wrong mental model of what your code’s doing, and you can find that out just as easily by inspecting a couple of values through the print statements.If I were on some codebase that you were also working on, what should I do to make it as easy as possible to understand?I’d say short and well-named methods. The one thing I like to do when I’m looking at code is to find out where a value comes from, and the more layers of indirection there are, particularly DI [dependency injection] frameworks, the harder it is to find out where something’s come from. I really hate that. I want to know if the value come from the user here or is a constant here, and if I can’t find that out, that makes code very hard to understand for me.As a tester, where do you think the split should lie between software engineers and testers?I think the split is less on areas of the code you write and more what you’re designing and creating. The developers put a structure on the code, while my major role is to say which tests we should have, whether we should test that, or it’s not worth testing that because it’s a tiny function in code that nobody’s ever actually going to see. So it’s not a split in the code, it’s a split in what you’re thinking about. Saying what code we should write, but alternatively what code we should take out.In your experience, do the software engineers tend to do much testing themselves?They tend to control the lowest layer of tests. And, depending on how the balance of people is in the team, they might write some of the higher levels of test. Or that might go to the testers. I’m the only tester on my team with three other developers, so they’ll be writing quite a lot of the actual test code, with input from me as to whether we should test that functionality, whereas on other teams, where it’s been more equal numbers, the testers have written pretty much all of the high level tests, just because that’s the best use of resource.If you could shuffle resources around however you liked, do you think that the developers should be writing those high-level tests?I think they should be writing them occasionally. It helps when they have an understanding of how testing code works and possibly what assumptions we’ve made in tests, and they can say “actually, it doesn’t work like that under the hood so you’ve missed this whole area”. It’s one of those agile things that everyone on the team should be at least comfortable doing the various jobs. So if the developers can write test code then I think that’s a very good thing.So you think testers should be able to write production code?Yes, although given most testers skills at coding, I wouldn’t advise it too much! I have written a few things, and I did make a few changes that have actually gone into our production code base. They’re not necessarily running every time but they are there. I think having that mix of skill sets is really useful. In some ways we’re using our own product to test itself, so being able to make those changes where it’s not working saves me a round-trip through the developers. It can be really annoying if the developers have no time to make a change, and I can’t touch the code.If the software engineers are consistently writing tests at all levels, what role do you think the role of a tester is?I think on a team like that, those distinctions aren’t quite so useful. There’ll be two cases. There’s either the case where the developers think they’ve written good tests, but you still need someone with a test engineer mind-set to go through the tests and validate that it’s a useful set, or the correct set for that code. Or they won’t actually be pure developers, they’ll have that mix of test ability in there.I think having slightly more distinct roles is useful. When it starts to blur, then you lose that view of the tests as a whole. The tester job is not to create tests, it’s to validate the quality of the product, and you don’t do that just by writing tests. There’s more things you’ve got to keep in your mind. And I think when you blur the roles, you start to lose that end of the tester.So because you’re working on those features, you lose that holistic view of the whole system?Yeah, and anyone who’s worked on the feature shouldn’t be testing it. You always need to have it tested it by someone who didn’t write it. Otherwise you’re a bit too close and you assume “yes, people will only use it that way”, but the tester will come along and go “how do people use this? How would our most idiotic user use this?”. I might not test that because it might be completely irrelevant. But it’s coming in and trying to have a different set of assumptions.Are you a believer that it should all be automated if possible?Not entirely. So an automated test is always better than a manual test for the long-term, but there’s still nothing that beats a human sitting in front of the application and thinking “What could I do at this point?”. The automated test is very good but they follow that strict path, and they never check anything off the path. The human tester will look at things that they weren’t expecting, whereas the automated test can only ever go “Is that value correct?” in many respects, and it won’t notice that on the other side of the screen you’re showing something completely wrong. And that value might have been checked independently, but you always find a few odd interactions when you’re going through something manually, and you always need to go through something manually to start with anyway, otherwise you won’t know where the important bits to write your automation are.When you’re doing that manual testing, do you think it’s important to do that across the entire product, or just the bits that you’ve touched recently?I think it’s important to do it mostly on the bits you’ve touched, but you can’t ignore the rest of the product. Unless you’re dealing with a very, very self-contained bit, you’re almost always encounter other bits of the product along the way. Most testers I know, even if they are looking at just one path, they’ll keep open and move around a bit anyway, just because they want to find something that’s broken. If we find that your path is right, we’ll go out and hunt something else.How do you think this fits into the idea of continuously deploying, so long as the tests pass?With deploying a website it’s a bit different because you can always pull it back. If you’re deploying an application to customers, when you’ve released it, it’s out there, you can’t pull it back. Someone’s going to keep it, no matter how hard you try there will be a few installations that stay around. So I’d always have at least a human element on that path. With websites, you could probably automate straight out, or at least straight out to an internal environment or a single server in a cloud of fifty that will serve some people. But I don’t think you should release to everyone just on automated tests passing.You’ve already mentioned using BASIC and C# — are there any other languages that you’ve used?I’ve used a few. That’s something that has changed more recently, I’ve become familiar with more languages. Before I started at Red Gate I learnt a bit of C. Then last year, I taught myself Python which I actually really enjoyed using. I’ve also come across another language called Vala, which is sort of a C#-like language. It’s basically a pre-processor for C, but it has very nice syntax. I think that’s currently my favourite language.Any particular reason for trying Vala?I have a completely Linux environment at home, and I’ve been looking for a nice language, and C# just doesn’t cut it because I won’t touch Mono. So, I was looking for something like C# but that was useable in an open source environment, and Vala’s what I found. C#’s got a few features that Vala doesn’t, and Vala’s got a few features where I think “It would be awesome if C# had that”.What are some of the features that it’s missing?Extension methods. And I think that’s the only one that really bugs me. I like to use them when I’m writing C# because it makes some things really easy, especially with libraries that you can’t touch the internals of. It doesn’t have method overloading, which is sometimes annoying.Where it does win over C#?Everything is non-nullable by default, you never have to check that something’s unexpectedly null.Also, Vala has code contracts. This is starting to come in C# 4, but the way it works in Vala is that you specify requirements in short phrases as part of your function signature and they stick to the signature, so that when you inherit it, it has exactly the same code contract as the base one, or when you inherit from an interface, you have to match the signature exactly. Just using those makes you think a bit more about how you’re writing your method, it’s not an afterthought when you’ve got contracts from base classes given to you, you can’t change it. Which I think is a lot nicer than the way C# handles it. When are those actually checked?They’re checked both at compile and run-time. The compile-time checking isn’t very strong yet, it’s quite a new feature in the compiler, and because it compiles down to C, you can write C code and interface with your methods, so you can bypass that compile-time check anyway. So there’s an extra runtime check, and if you violate one of the contracts at runtime, it’s game over for your program, there’s no exception to catch, it’s just goodbye!One thing I dislike about C# is the exceptions. You write a bit of code and fifty exceptions could come from any point in your ten lines, and you can’t mentally model how those exceptions are going to come out, and you can’t even predict them based on the functions you’re calling, because if you’ve accidentally got a derived class there instead of a base class, that can throw a completely different set of exceptions. So I’ve got no way of mentally modelling those, whereas in Vala they’re checked like Java, so you know only these exceptions can come out. You know in advance the error conditions.I think Raymond Chen on Old New Thing says “the only thing you know when you throw an exception is that you’re in an invalid state somewhere in your program, so just kill it and be done with it!”You said you’ve also learnt bits of Python. How did you find that compared to Vala and C#?Very different because of the dynamic typing. I’ve been writing a website for my own use. I’m quite into photography, so I take photos off my camera, post-process them, dump them in a file, and I get a webpage with all my thumbnails. So sort of like Picassa, but written by myself because I wanted something to learn Python with. There are some things that are really nice, I just found it really difficult to cope with the fact that I’m not quite sure what this object type that I’m passed is, I might not ever be sure, so it can randomly blow up on me. But once I train myself to ignore that and just say “well, I’m fairly sure it’s going to be something that looks like this, so I’ll use it like this”, then it’s quite nice.Any particular features that you’ve appreciated?I don’t like any particular feature, it’s just very straightforward to work with. It’s very quick to write something in, particularly as you don’t have to worry that you’ve changed something that affects a different part of the program. If you have, then that part blows up, but I can get this part working right now.If you were doing a big project, would you be willing to do it in Python rather than C# or Vala?I think I might be willing to try something bigger or long term with Python. We’re currently doing an ASP.NET MVC project on C#, and I don’t like the amount of reflection. There’s a lot of magic that pulls values out, and it’s all done under the scenes. It’s almost managed to put a dynamic type system on top of C#, which in many ways destroys the language to me, whereas if you’re already in a dynamic language, having things done dynamically is much more natural. In many ways, you get the worst of both worlds. I think for web projects, I would go with Python again, whereas for anything desktop, command-line or GUI-based, I’d probably go for C# or Vala, depending on what environment I’m in.It’s the fact that you can gain from the strong typing in ways that you can’t so much on the web app. Or, in a web app, you have to use dynamic typing at some point, or you have to write a hell of a lot of boilerplate, and I’d rather use the dynamic typing than write the boilerplate.What do you think separates great programmers from everyone else?Probably design choices. Choosing to write it a piece of code one way or another. For any given program you ask me to write, I could probably do it five thousand ways. A programmer who is capable will see four or five of them, and choose one of the better ones. The excellent programmer will see the largest proportion and manage to pick the best one very quickly without having to think too much about it. I think that’s probably what separates, is the speed at which they can see what’s the best path to write the program in. More Red Gater Coder interviews

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• Grandparent – Parent – Child Reports in SQL Developer

  - by thatjeffsmith

  You’ll never see one of these family stickers on my car, but I promise not to judge…much. Parent – Child reports are pretty straightforward in Oracle SQL Developer. You have a ‘parent’ report, and then one or more ‘child’ reports which are based off of a value in a selected row or value from the parent. If you need a quick tutorial to get up to speed on the subject, go ahead and take 5 minutes Shortly before I left for vacation 2 weeks agao, I got an interesting question from one of my Twitter Followers: @thatjeffsmith any luck with the #Oracle awr reports in #SQLDeveloper?This is easy with multi generation parent>child Done in #dbvisualizer — Ronald Rood (@Ik_zelf) August 26, 2012 Now that I’m back from vacation, I can tell Ronald and everyone else that the answer is ‘Yes!’ And here’s how Time to Get Out Your XML Editor Don’t have one? That’s OK, SQL Developer can edit XML files. While the Reporting interface doesn’t surface the ability to create multi-generational reports, the underlying code definitely supports it. We just need to hack away at the XML that powers a report. For this example I’m going to start simple. A query that brings back DEPARTMENTs, then EMPLOYEES, then JOBs. We can build the first two parts of the report using the report editor. A Parent-Child report in Oracle SQL Developer (Departments – Employees) Save the Report to XML Once you’ve generated the XML file, open it with your favorite XML editor. For this example I’ll be using the build-it XML editor in SQL Developer. SQL Developer Reports in their raw XML glory! Right after the PDF element in the XML document, we can start a new ‘child’ report by inserting a DISPLAY element. I just copied and pasted the existing ‘display’ down so I wouldn’t have to worry about screwing anything up. Note I also needed to change the ‘master’ name so it wouldn’t confuse SQL Developer when I try to import/open a report that has the same name. Also I needed to update the binds tags to reflect the names from the child versus the original parent report. This is pretty easy to figure out on your own actually – I mean I’m no real developer and I got it pretty quick. <?xml version="1.0" encoding="UTF-8" ?> <displays> <display id="92857fce-0139-1000-8006-7f0000015340" type="" style="Table" enable="true"> <name><![CDATA[Grandparent]]></name> <description><![CDATA[]]></description> <tooltip><![CDATA[]]></tooltip> <drillclass><![CDATA[null]]></drillclass> <CustomValues> <TYPE>horizontal</TYPE> </CustomValues> <query> <sql><![CDATA[select * from hr.departments]]></sql> </query> <pdf version="VERSION_1_7" compression="CONTENT"> <docproperty title="" author="" subject="" keywords="" /> <cell toppadding="2" bottompadding="2" leftpadding="2" rightpadding="2" horizontalalign="LEFT" verticalalign="TOP" wrap="true" /> <column> <heading font="Courier" size="10" style="NORMAL" color="-16777216" rowshading="-1" labeling="FIRST_PAGE" /> <footing font="Courier" size="10" style="NORMAL" color="-16777216" rowshading="-1" labeling="NONE" /> <blob blob="NONE" zip="false" /> </column> <table font="Courier" size="10" style="NORMAL" color="-16777216" userowshading="false" oddrowshading="-1" evenrowshading="-1" showborders="true" spacingbefore="12" spacingafter="12" horizontalalign="LEFT" /> <header enable="false" generatedate="false"> <data> null </data> </header> <footer enable="false" generatedate="false"> <data value="null" /> </footer> <security enable="false" useopenpassword="false" openpassword="" encryption="EXCLUDE_METADATA"> <permission enable="false" permissionpassword="" allowcopying="true" allowprinting="true" allowupdating="false" allowaccessdevices="true" /> </security> <pagesetup papersize="LETTER" orientation="1" measurement="in" margintop="1.0" marginbottom="1.0" marginleft="1.0" marginright="1.0" /> </pdf> <display id="null" type="" style="Table" enable="true"> <name><![CDATA[Parent]]></name> <description><![CDATA[]]></description> <tooltip><![CDATA[]]></tooltip> <drillclass><![CDATA[null]]></drillclass> <CustomValues> <TYPE>horizontal</TYPE> </CustomValues> <query> <sql><![CDATA[select * from hr.employees where department_id = EPARTMENT_ID]]></sql> <binds> <bind id="DEPARTMENT_ID"> <prompt><![CDATA[DEPARTMENT_ID]]></prompt> <tooltip><![CDATA[DEPARTMENT_ID]]></tooltip> <value><![CDATA[NULL_VALUE]]></value> </bind> </binds> </query> <pdf version="VERSION_1_7" compression="CONTENT"> <docproperty title="" author="" subject="" keywords="" /> <cell toppadding="2" bottompadding="2" leftpadding="2" rightpadding="2" horizontalalign="LEFT" verticalalign="TOP" wrap="true" /> <column> <heading font="Courier" size="10" style="NORMAL" color="-16777216" rowshading="-1" labeling="FIRST_PAGE" /> <footing font="Courier" size="10" style="NORMAL" color="-16777216" rowshading="-1" labeling="NONE" /> <blob blob="NONE" zip="false" /> </column> <table font="Courier" size="10" style="NORMAL" color="-16777216" userowshading="false" oddrowshading="-1" evenrowshading="-1" showborders="true" spacingbefore="12" spacingafter="12" horizontalalign="LEFT" /> <header enable="false" generatedate="false"> <data> null </data> </header> <footer enable="false" generatedate="false"> <data value="null" /> </footer> <security enable="false" useopenpassword="false" openpassword="" encryption="EXCLUDE_METADATA"> <permission enable="false" permissionpassword="" allowcopying="true" allowprinting="true" allowupdating="false" allowaccessdevices="true" /> </security> <pagesetup papersize="LETTER" orientation="1" measurement="in" margintop="1.0" marginbottom="1.0" marginleft="1.0" marginright="1.0" /> </pdf> <display id="null" type="" style="Table" enable="true"> <name><![CDATA[Child]]></name> <description><![CDATA[]]></description> <tooltip><![CDATA[]]></tooltip> <drillclass><![CDATA[null]]></drillclass> <CustomValues> <TYPE>horizontal</TYPE> </CustomValues> <query> <sql><![CDATA[select * from hr.jobs where job_id = :JOB_ID]]></sql> <binds> <bind id="JOB_ID"> <prompt><![CDATA[JOB_ID]]></prompt> <tooltip><![CDATA[JOB_ID]]></tooltip> <value><![CDATA[NULL_VALUE]]></value> </bind> </binds> </query> <pdf version="VERSION_1_7" compression="CONTENT"> <docproperty title="" author="" subject="" keywords="" /> <cell toppadding="2" bottompadding="2" leftpadding="2" rightpadding="2" horizontalalign="LEFT" verticalalign="TOP" wrap="true" /> <column> <heading font="Courier" size="10" style="NORMAL" color="-16777216" rowshading="-1" labeling="FIRST_PAGE" /> <footing font="Courier" size="10" style="NORMAL" color="-16777216" rowshading="-1" labeling="NONE" /> <blob blob="NONE" zip="false" /> </column> <table font="Courier" size="10" style="NORMAL" color="-16777216" userowshading="false" oddrowshading="-1" evenrowshading="-1" showborders="true" spacingbefore="12" spacingafter="12" horizontalalign="LEFT" /> <header enable="false" generatedate="false"> <data> null </data> </header> <footer enable="false" generatedate="false"> <data value="null" /> </footer> <security enable="false" useopenpassword="false" openpassword="" encryption="EXCLUDE_METADATA"> <permission enable="false" permissionpassword="" allowcopying="true" allowprinting="true" allowupdating="false" allowaccessdevices="true" /> </security> <pagesetup papersize="LETTER" orientation="1" measurement="in" margintop="1.0" marginbottom="1.0" marginleft="1.0" marginright="1.0" /> </pdf> </display> </display> </display> </displays> Save the file and ‘Open Report…’ You’ll see your new report name in the tree. You just need to double-click it to open it. Here’s what it looks like running A 3 generation family Now Let’s Build an AWR Text Report Ronald wanted to have the ability to query AWR snapshots and generate the AWR reports. That requires a few inputs, including a START and STOP snapshot ID. That basically tells AWR what time period to use for generating the report. And here’s where it gets tricky. We’ll need to use aliases for the SNAP_ID column. Since we’re using the same column name from 2 different queries, we need to use different bind variables. Fortunately for us, SQL Developer’s clever enough to use the column alias as the BIND. Here’s what I mean: Grandparent Query SELECT snap_id start1, begin_interval_time, end_interval_time FROM dba_hist_snapshot ORDER BY 1 asc Parent Query SELECT snap_id stop1, begin_interval_time, end_interval_time, :START1 carry FROM dba_hist_snapshot WHERE snap_id > :START1 ORDER BY 1 asc And here’s where it gets even trickier – you can’t reference a bind from outside the parent query. My grandchild report can’t reference a value from the grandparent report. So I just carry the selected value down to the parent. In my parent query SELECT you see the ‘:START1′ at the end? That’s making that value available to me when I use it in my grandchild query. To complicate things a bit further, I can’t have a column name with a ‘:’ in it, or SQL Developer will get confused when I try to reference the value of the variable with the ‘:’ – and ‘::Name’ doesn’t work. But that’s OK, just alias it. Grandchild Query Select Output From Table(Dbms_Workload_Repository.Awr_Report_Text(1298953802, 1,:CARRY, :STOP1)); Ok, and the last trick – I hard-coded my report to use my database’s DB_ID and INST_ID into the AWR package call. Now a smart person could figure out a way to make that work on any database, but I got lazy and and ran out of time. But this should be far enough for you to take it from here. Here’s what my report looks like now: Caution: don’t run this if you haven’t licensed Enterprise Edition with Diagnostic Pack. The Raw XML for this AWR Report <?xml version="1.0" encoding="UTF-8" ?> <displays> <display id="927ba96c-0139-1000-8001-7f0000015340" type="" style="Table" enable="true"> <name><![CDATA[AWR Start Stop Report Final]]></name> <description><![CDATA[]]></description> <tooltip><![CDATA[]]></tooltip> <drillclass><![CDATA[null]]></drillclass> <CustomValues> <TYPE>horizontal</TYPE> </CustomValues> <query> <sql><![CDATA[SELECT snap_id start1, begin_interval_time, end_interval_time FROM dba_hist_snapshot ORDER BY 1 asc]]></sql> </query> <display id="null" type="" style="Table" enable="true"> <name><![CDATA[Stop SNAP_ID]]></name> <description><![CDATA[]]></description> <tooltip><![CDATA[]]></tooltip> <drillclass><![CDATA[null]]></drillclass> <CustomValues> <TYPE>horizontal</TYPE> </CustomValues> <query> <sql><![CDATA[SELECT snap_id stop1, begin_interval_time, end_interval_time, :START1 carry FROM dba_hist_snapshot WHERE snap_id > :START1 ORDER BY 1 asc]]></sql> </query> <display id="null" type="" style="Table" enable="true"> <name><![CDATA[AWR Report]]></name> <description><![CDATA[]]></description> <tooltip><![CDATA[]]></tooltip> <drillclass><![CDATA[null]]></drillclass> <CustomValues> <TYPE>horizontal</TYPE> </CustomValues> <query> <sql><![CDATA[Select Output From Table(Dbms_Workload_Repository.Awr_Report_Text(1298953802, 1,:CARRY, :STOP1 ))]]></sql> </query> </display> </display> </display> </displays> Should We Build Support for Multiple Levels of Reports into the User Interface? Let us know! A comment here or a suggestion on our SQL Developer Exchange might help your case!

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• ANTS Memory Profiler 7.0 Review

  - by Michael B. McLaughlin

  (This is my first review as a part of the GeeksWithBlogs.net Influencers program. It’s a program in which I (and the others who have been selected for it) get the opportunity to check out new products and services and write reviews about them. We don’t get paid for this, but we do generally get to keep a copy of the software or retain an account for some period of time on the service that we review. In this case I received a copy of Red Gate Software’s ANTS Memory Profiler 7.0, which was released in January. I don’t have any upgrade rights nor is my review guided, restrained, influenced, or otherwise controlled by Red Gate or anyone else. But I do get to keep the software license. I will always be clear about what I received whenever I do a review – I leave it up to you to decide whether you believe I can be objective. I believe I can be. If I used something and really didn’t like it, keeping a copy of it wouldn’t be worth anything to me. In that case though, I would simply uninstall/deactivate/whatever the software or service and tell the company what I didn’t like about it so they could (hopefully) make it better in the future. I don’t think it’d be polite to write up a terrible review, nor do I think it would be a particularly good use of my time. There are people who get paid for a living to review things, so I leave it to them to tell you what they think is bad and why. I’ll only spend my time telling you about things I think are good.) Overview of Common .NET Memory Problems When coming to land of managed memory from the wilds of unmanaged code, it’s easy to say to one’s self, “Wow! Now I never have to worry about memory problems again!” But this simply isn’t true. Managed code environments, such as .NET, make many, many things easier. You will never have to worry about memory corruption due to a bad pointer, for example (unless you’re working with unsafe code, of course). But managed code has its own set of memory concerns. For example, failing to unsubscribe from events when you are done with them leaves the publisher of an event with a reference to the subscriber. If you eliminate all your own references to the subscriber, then that memory is effectively lost since the GC won’t delete it because of the publishing object’s reference. When the publishing object itself becomes subject to garbage collection then you’ll get that memory back finally, but that could take a very long time depending of the life of the publisher. Another common source of resource leaks is failing to properly release unmanaged resources. When writing a class that contains members that hold unmanaged resources (e.g. any of the Stream-derived classes, IsolatedStorageFile, most classes ending in “Reader” or “Writer”), you should always implement IDisposable, making sure to use a properly written Dispose method. And when you are using an instance of a class that implements IDisposable, you should always make sure to use a 'using' statement in order to ensure that the object’s unmanaged resources are disposed of properly. (A ‘using’ statement is a nicer, cleaner looking, and easier to use version of a try-finally block. The compiler actually translates it as though it were a try-finally block. Note that Code Analysis warning 2202 (CA2202) will often be triggered by nested using blocks. A properly written dispose method ensures that it only runs once such that calling dispose multiple times should not be a problem. Nonetheless, CA2202 exists and if you want to avoid triggering it then you should write your code such that only the innermost IDisposable object uses a ‘using’ statement, with any outer code making use of appropriate try-finally blocks instead). Then, of course, there are situations where you are operating in a memory-constrained environment or else you want to limit or even eliminate allocations within a certain part of your program (e.g. within the main game loop of an XNA game) in order to avoid having the GC run. On the Xbox 360 and Windows Phone 7, for example, for every 1 MB of heap allocations you make, the GC runs; the added time of a GC collection can cause a game to drop frames or run slowly thereby making it look bad. Eliminating allocations (or else minimizing them and calling an explicit Collect at an appropriate time) is a common way of avoiding this (the other way is to simplify your heap so that the GC’s latency is low enough not to cause performance issues). ANTS Memory Profiler 7.0 When the opportunity to review Red Gate’s recently released ANTS Memory Profiler 7.0 arose, I jumped at it. In order to review it, I was given a free copy (which does not include upgrade rights for future versions) which I am allowed to keep. For those of you who are familiar with ANTS Memory Profiler, you can find a list of new features and enhancements here. If you are an experienced .NET developer who is familiar with .NET memory management issues, ANTS Memory Profiler is great. More importantly still, if you are new to .NET development or you have no experience or limited experience with memory profiling, ANTS Memory Profiler is awesome. From the very beginning, it guides you through the process of memory profiling. If you’re experienced and just want dive in however, it doesn’t get in your way. The help items GAHSFLASHDAJLDJA are well designed and located right next to the UI controls so that they are easy to find without being intrusive. When you first launch it, it presents you with a “Getting Started” screen that contains links to “Memory profiling video tutorials”, “Strategies for memory profiling”, and the “ANTS Memory Profiler forum”. I’m normally the kind of person who looks at a screen like that only to find the “Don’t show this again” checkbox. Since I was doing a review, though, I decided I should examine them. I was pleasantly surprised. The overview video clocks in at three minutes and fifty seconds. It begins by showing you how to get started profiling an application. It explains that profiling is done by taking memory snapshots periodically while your program is running and then comparing them. ANTS Memory Profiler (I’m just going to call it “ANTS MP” from here) analyzes these snapshots in the background while your application is running. It briefly mentions a new feature in Version 7, a new API that give you the ability to trigger snapshots from within your application’s source code (more about this below). You can also, and this is the more common way you would do it, take a memory snapshot at any time from within the ANTS MP window by clicking the “Take Memory Snapshot” button in the upper right corner. The overview video goes on to demonstrate a basic profiling session on an application that pulls information from a database and displays it. It shows how to switch which snapshots you are comparing, explains the different sections of the Summary view and what they are showing, and proceeds to show you how to investigate memory problems using the “Instance Categorizer” to track the path from an object (or set of objects) to the GC’s root in order to find what things along the path are holding a reference to it/them. For a set of objects, you can then click on it and get the “Instance List” view. This displays all of the individual objects (including their individual sizes, values, etc.) of that type which share the same path to the GC root. You can then click on one of the objects to generate an “Instance Retention Graph” view. This lets you track directly up to see the reference chain for that individual object. In the overview video, it turned out that there was an event handler which was holding on to a reference, thereby keeping a large number of strings that should have been freed in memory. Lastly the video shows the “Class List” view, which lets you dig in deeply to find problems that might not have been clear when following the previous workflow. Once you have at least one memory snapshot you can begin analyzing. The main interface is in the “Analysis” tab. You can also switch to the “Session Overview” tab, which gives you several bar charts highlighting basic memory data about the snapshots you’ve taken. If you hover over the individual bars (and the individual colors in bars that have more than one), you will see a detailed text description of what the bar is representing visually. The Session Overview is good for a quick summary of memory usage and information about the different heaps. You are going to spend most of your time in the Analysis tab, but it’s good to remember that the Session Overview is there to give you some quick feedback on basic memory usage stats. As described above in the summary of the overview video, there is a certain natural workflow to the Analysis tab. You’ll spin up your application and take some snapshots at various times such as before and after clicking a button to open a window or before and after closing a window. Taking these snapshots lets you examine what is happening with memory. You would normally expect that a lot of memory would be freed up when closing a window or exiting a document. By taking snapshots before and after performing an action like that you can see whether or not the memory is really being freed. If you already know an area that’s giving you trouble, you can run your application just like normal until just before getting to that part and then you can take a few strategic snapshots that should help you pin down the problem. Something the overview didn’t go into is how to use the “Filters” section at the bottom of ANTS MP together with the Class List view in order to narrow things down. The video tutorials page has a nice 3 minute intro video called “How to use the filters”. It’s a nice introduction and covers some of the basics. I’m going to cover a bit more because I think they’re a really neat, really helpful feature. Large programs can bring up thousands of classes. Even simple programs can instantiate far more classes than you might realize. In a basic .NET 4 WPF application for example (and when I say basic, I mean just MainWindow.xaml with a button added to it), the unfiltered Class List view will have in excess of 1000 classes (my simple test app had anywhere from 1066 to 1148 classes depending on which snapshot I was using as the “Current” snapshot). This is amazing in some ways as it shows you how in stark detail just how immensely powerful the WPF framework is. But hunting through 1100 classes isn’t productive, no matter how cool it is that there are that many classes instantiated and doing all sorts of awesome things. Let’s say you wanted to examine just the classes your application contains source code for (in my simple example, that would be the MainWindow and App). Under “Basic Filters”, click on “Classes with source” under “Show only…”. Voilà. Down from 1070 classes in the snapshot I was using as “Current” to 2 classes. If you then click on a class’s name, it will show you (to the right of the class name) two little icon buttons. Hover over them and you will see that you can click one to view the Instance Categorizer for the class and another to view the Instance List for the class. You can also show classes based on which heap they live on. If you chose both a Baseline snapshot and a Current snapshot then you can use the “Comparing snapshots” filters to show only: “New objects”; “Surviving objects”; “Survivors in growing classes”; or “Zombie objects” (if you aren’t sure what one of these means, you can click the helpful “?” in a green circle icon to bring up a popup that explains them and provides context). Remember that your selection(s) under the “Show only…” heading will still apply, so you should update those selections to make sure you are seeing the view you want. There are also links under the “What is my memory problem?” heading that can help you diagnose the problems you are seeing including one for “I don’t know which kind I have” for situations where you know generally that your application has some problems but aren’t sure what the behavior you have been seeing (OutOfMemoryExceptions, continually growing memory usage, larger memory use than expected at certain points in the program). The Basic Filters are not the only filters there are. “Filter by Object Type” gives you the ability to filter by: “Objects that are disposable”; “Objects that are/are not disposed”; “Objects that are/are not GC roots” (GC roots are things like static variables); and “Objects that implement _______”. “Objects that implement” is particularly neat. Once you check the box, you can then add one or more classes and interfaces that an object must implement in order to survive the filtering. Lastly there is “Filter by Reference”, which gives you the option to pare down the list based on whether an object is “Kept in memory exclusively by” a particular item, a class/interface, or a namespace; whether an object is “Referenced by” one or more of those choices; and whether an object is “Never referenced by” one or more of those choices. Remember that filtering is cumulative, so anything you had set in one of the filter sections still remains in effect unless and until you go back and change it. There’s quite a bit more to ANTS MP – it’s a very full featured product – but I think I touched on all of the most significant pieces. You can use it to debug: a .NET executable; an ASP.NET web application (running on IIS); an ASP.NET web application (running on Visual Studio’s built-in web development server); a Silverlight 4 browser application; a Windows service; a COM+ server; and even something called an XBAP (local XAML browser application). You can also attach to a .NET 4 process to profile an application that’s already running. The startup screen also has a large number of “Charting Options” that let you adjust which statistics ANTS MP should collect. The default selection is a good, minimal set. It’s worth your time to browse through the charting options to examine other statistics that may also help you diagnose a particular problem. The more statistics ANTS MP collects, the longer it will take to collect statistics. So just turning everything on is probably a bad idea. But the option to selectively add in additional performance counters from the extensive list could be a very helpful thing for your memory profiling as it lets you see additional data that might provide clues about a particular problem that has been bothering you. ANTS MP integrates very nicely with all versions of Visual Studio that support plugins (i.e. all of the non-Express versions). Just note that if you choose “Profile Memory” from the “ANTS” menu that it will launch profiling for whichever project you have set as the Startup project. One quick tip from my experience so far using ANTS MP: if you want to properly understand your memory usage in an application you’ve written, first create an “empty” version of the type of project you are going to profile (a WPF application, an XNA game, etc.) and do a quick profiling session on that so that you know the baseline memory usage of the framework itself. By “empty” I mean just create a new project of that type in Visual Studio then compile it and run it with profiling – don’t do anything special or add in anything (except perhaps for any external libraries you’re planning to use). The first thing I tried ANTS MP out on was a demo XNA project of an editor that I’ve been working on for quite some time that involves a custom extension to XNA’s content pipeline. The first time I ran it and saw the unmanaged memory usage I was convinced I had some horrible bug that was creating extra copies of texture data (the demo project didn’t have a lot of texture data so when I saw a lot of unmanaged memory I instantly figured I was doing something wrong). Then I thought to run an empty project through and when I saw that the amount of unmanaged memory was virtually identical, it dawned on me that the CLR itself sits in unmanaged memory and that (thankfully) there was nothing wrong with my code! Quite a relief. Earlier, when discussing the overview video, I mentioned the API that lets you take snapshots from within your application. I gave it a quick trial and it’s very easy to integrate and make use of and is a really nice addition (especially for projects where you want to know what, if any, allocations there are in a specific, complicated section of code). The only concern I had was that if I hadn’t watched the overview video I might never have known it existed. Even then it took me five minutes of hunting around Red Gate’s website before I found the “Taking snapshots from your code" article that explains what DLL you need to add as a reference and what method of what class you should call in order to take an automatic snapshot (including the helpful warning to wrap it in a try-catch block since, under certain circumstances, it can raise an exception, such as trying to call it more than 5 times in 30 seconds. The difficulty in discovering and then finding information about the automatic snapshots API was one thing I thought could use improvement. Another thing I think would make it even better would be local copies of the webpages it links to. Although I’m generally always connected to the internet, I imagine there are more than a few developers who aren’t or who are behind very restrictive firewalls. For them (and for me, too, if my internet connection happens to be down), it would be nice to have those documents installed locally or to have the option to download an additional “documentation” package that would add local copies. Another thing that I wish could be easier to manage is the Filters area. Finding and setting individual filters is very easy as is understanding what those filter do. And breaking it up into three sections (basic, by object, and by reference) makes sense. But I could easily see myself running a long profiling session and forgetting that I had set some filter a long while earlier in a different filter section and then spending quite a bit of time trying to figure out why some problem that was clearly visible in the data wasn’t showing up in, e.g. the instance list before remembering to check all the filters for that one setting that was only culling a few things from view. Some sort of indicator icon next to the filter section names that appears you have at least one filter set in that area would be a nice visual clue to remind me that “oh yeah, I told it to only show objects on the Gen 2 heap! That’s why I’m not seeing those instances of the SuperMagic class!” Something that would be nice (but that Red Gate cannot really do anything about) would be if this could be used in Windows Phone 7 development. If Microsoft and Red Gate could work together to make this happen (even if just on the WP7 emulator), that would be amazing. Especially given the memory constraints that apps and games running on mobile devices need to work within, a good memory profiler would be a phenomenally helpful tool. If anyone at Microsoft reads this, it’d be really great if you could make something like that happen. Perhaps even a (subsidized) custom version just for WP7 development. (For XNA games, of course, you can create a Windows version of the game and use ANTS MP on the Windows version in order to get a better picture of your memory situation. For Silverlight on WP7, though, there’s quite a bit of educated guess work and WeakReference creation followed by forced collections in order to find the source of a memory problem.) The only other thing I found myself wanting was a “Back” button. Between my Windows Phone 7, Zune, and other things, I’ve grown very used to having a “back stack” that lets me just navigate back to where I came from. The ANTS MP interface is surprisingly easy to use given how much it lets you do, and once you start using it for any amount of time, you learn all of the different areas such that you know where to go. And it does remember the state of the areas you were previously in, of course. So if you go to, e.g., the Instance Retention Graph from the Class List and then return back to the Class List, it will remember which class you had selected and all that other state information. Still, a “Back” button would be a welcome addition to a future release. Bottom Line ANTS Memory Profiler is not an inexpensive tool. But my time is valuable. I can easily see ANTS MP saving me enough time tracking down memory problems to justify it on a cost basis. More importantly to me, knowing what is happening memory-wise in my programs and having the confidence that my code doesn’t have any hidden time bombs in it that will cause it to OOM if I leave it running for longer than I do when I spin it up real quickly for debugging or just to see how a new feature looks and feels is a good feeling. It’s a feeling that I like having and want to continue to have. I got the current version for free in order to review it. Having done so, I’ve now added it to my must-have tools and will gladly lay out the money for the next version when it comes out. It has a 14 day free trial, so if you aren’t sure if it’s right for you or if you think it seems interesting but aren’t really sure if it’s worth shelling out the money for it, give it a try.

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• Towards Database Continuous Delivery – What Next after Continuous Integration? A Checklist

  - by Ben Rees

  .dbd-banner p{ font-size:0.75em; padding:0 0 10px; margin:0 } .dbd-banner p span{ color:#675C6D; } .dbd-banner p:last-child{ padding:0; } @media ALL and (max-width:640px){ .dbd-banner{ background:#f0f0f0; padding:5px; color:#333; margin-top: 5px; } } -- Database delivery patterns & practices STAGE 4 AUTOMATED DEPLOYMENT If you’ve been fortunate enough to get to the stage where you’ve implemented some sort of continuous integration process for your database updates, then hopefully you’re seeing the benefits of that investment – constant feedback on changes your devs are making, advanced warning of data loss (prior to the production release on Saturday night!), a nice suite of automated tests to check business logic, so you know it’s going to work when it goes live, and so on. But what next? What can you do to improve your delivery process further, moving towards a full continuous delivery process for your database? In this article I describe some of the issues you might need to tackle on the next stage of this journey, and how to plan to overcome those obstacles before they appear. Our Database Delivery Learning Program consists of four stages, really three – source controlling a database, running continuous integration processes, then how to set up automated deployment (the middle stage is split in two – basic and advanced continuous integration, making four stages in total). If you’ve managed to work through the first three of these stages – source control, basic, then advanced CI, then you should have a solid change management process set up where, every time one of your team checks in a change to your database (whether schema or static reference data), this change gets fully tested automatically by your CI server. But this is only part of the story. Great, we know that our updates work, that the upgrade process works, that the upgrade isn’t going to wipe our 4Tb of production data with a single DROP TABLE. But – how do you get this (fully tested) release live? Continuous delivery means being always ready to release your software at any point in time. There’s a significant gap between your latest version being tested, and it being easily releasable. Just a quick note on terminology – there’s a nice piece here from Atlassian on the difference between continuous integration, continuous delivery and continuous deployment. This piece also gives a nice description of the benefits of continuous delivery. These benefits have been summed up by Jez Humble at Thoughtworks as: “Continuous delivery is a set of principles and practices to reduce the cost, time, and risk of delivering incremental changes to users” There’s another really useful piece here on Simple-Talk about the need for continuous delivery and how it applies to the database written by Phil Factor – specifically the extra needs and complexities of implementing a full CD solution for the database (compared to just implementing CD for, say, a web app). So, hopefully you’re convinced of moving on the the next stage! The next step after CI is to get some sort of automated deployment (or “release management”) process set up. But what should I do next? What do I need to plan and think about for getting my automated database deployment process set up? Can’t I just install one of the many release management tools available and hey presto, I’m ready! If only it were that simple. Below I list some of the areas that it’s worth spending a little time on, where a little planning and prep could go a long way. It’s also worth pointing out, that this should really be an evolving process. Depending on your starting point of course, it can be a long journey from your current setup to a full continuous delivery pipeline. If you’ve got a CI mechanism in place, you’re certainly a long way down that path. Nevertheless, we’d recommend evolving your process incrementally. Pages 157 and 129-141 of the book on Continuous Delivery (by Jez Humble and Dave Farley) have some great guidance on building up a pipeline incrementally: http://www.amazon.com/Continuous-Delivery-Deployment-Automation-Addison-Wesley/dp/0321601912 For now, in this post, we’ll look at the following areas for your checklist: You and Your Team Environments The Deployment Process Rollback and Recovery Development Practices You and Your Team It’s a cliché in the DevOps community that “It’s not all about processes and tools, really it’s all about a culture”. As stated in this DevOps report from Puppet Labs: “DevOps processes and tooling contribute to high performance, but these practices alone aren’t enough to achieve organizational success. The most common barriers to DevOps adoption are cultural: lack of manager or team buy-in, or the value of DevOps isn’t understood outside of a specific group”. Like most clichés, there’s truth in there – if you want to set up a database continuous delivery process, you need to get your boss, your department, your company (if relevant) onside. Why? Because it’s an investment with the benefits coming way down the line. But the benefits are huge – for HP, in the book A Practical Approach to Large-Scale Agile Development: How HP Transformed LaserJet FutureSmart Firmware, these are summarized as: -2008 to present: overall development costs reduced by 40% -Number of programs under development increased by 140% -Development costs per program down 78% -Firmware resources now driving innovation increased by a factor of 8 (from 5% working on new features to 40% But what does this mean? It means that, when moving to the next stage, to make that extra investment in automating your deployment process, it helps a lot if everyone is convinced that this is a good thing. That they understand the benefits of automated deployment and are willing to make the effort to transform to a new way of working. Incidentally, if you’re ever struggling to convince someone of the value I’d strongly recommend just buying them a copy of this book – a great read, and a very practical guide to how it can really work at a large org. I’ve spoken to many customers who have implemented database CI who describe their deployment process as “The point where automation breaks down. Up to that point, the CI process runs, untouched by human hand, but as soon as that’s finished we revert to manual.” This deployment process can involve, for example, a DBA manually comparing an environment (say, QA) to production, creating the upgrade scripts, reading through them, checking them against an Excel document emailed to him/her the night before, turning to page 29 in his/her notebook to double-check how replication is switched off and on for deployments, and so on and so on. Painful, error-prone and lengthy. But the point is, if this is something like your deployment process, telling your DBA “We’re changing everything you do and your toolset next week, to automate most of your role – that’s okay isn’t it?” isn’t likely to go down well. There’s some work here to bring him/her onside – to explain what you’re doing, why there will still be control of the deployment process and so on. Or of course, if you’re the DBA looking after this process, you have to do a similar job in reverse. You may have researched and worked out how you’d like to change your methodology to start automating your painful release process, but do the dev team know this? What if they have to start producing different artifacts for you? Will they be happy with this? Worth talking to them, to find out. As well as talking to your DBA/dev team, the other group to get involved before implementation is your manager. And possibly your manager’s manager too. As mentioned, unless there’s buy-in “from the top”, you’re going to hit problems when the implementation starts to get rocky (and what tool/process implementations don’t get rocky?!). You need to have support from someone senior in your organisation – someone you can turn to when you need help with a delayed implementation, lack of resources or lack of progress. Actions: Get your DBA involved (or whoever looks after live deployments) and discuss what you’re planning to do or, if you’re the DBA yourself, get the dev team up-to-speed with your plans, Get your boss involved too and make sure he/she is bought in to the investment. Environments Where are you going to deploy to? And really this question is – what environments do you want set up for your deployment pipeline? Assume everyone has “Production”, but do you have a QA environment? Dedicated development environments for each dev? Proper pre-production? I’ve seen every setup under the sun, and there is often a big difference between “What we want, to do continuous delivery properly” and “What we’re currently stuck with”. Some of these differences are: What we want What we’ve got Each developer with their own dedicated database environment A single shared “development” environment, used by everyone at once An Integration box used to test the integration of all check-ins via the CI process, along with a full suite of unit-tests running on that machine In fact if you have a CI process running, you’re likely to have some sort of integration server running (even if you don’t call it that!). Whether you have a full suite of unit tests running is a different question… Separate QA environment used explicitly for manual testing prior to release “We just test on the dev environments, or maybe pre-production” A proper pre-production (or “staging”) box that matches production as closely as possible Hopefully a pre-production box of some sort. But does it match production closely!? A production environment reproducible from source control A production box which has drifted significantly from anything in source control The big question is – how much time and effort are you going to invest in fixing these issues? In reality this just involves figuring out which new databases you’re going to create and where they’ll be hosted – VMs? Cloud-based? What about size/data issues – what data are you going to include on dev environments? Does it need to be masked to protect access to production data? And often the amount of work here really depends on whether you’re working on a new, greenfield project, or trying to update an existing, brownfield application. There’s a world if difference between starting from scratch with 4 or 5 clean environments (reproducible from source control of course!), and trying to re-purpose and tweak a set of existing databases, with all of their surrounding processes and quirks. But for a proper release management process, ideally you have: Dedicated development databases, An Integration server used for testing continuous integration and running unit tests. [NB: This is the point at which deployments are automatic, without human intervention. Each deployment after this point is a one-click (but human) action], QA – QA engineers use a one-click deployment process to automatically* deploy chosen releases to QA for testing, Pre-production. The environment you use to test the production release process, Production. * A note on the use of the word “automatic” – when carrying out automated deployments this does not mean that the deployment is happening without human intervention (i.e. that something is just deploying over and over again). It means that the process of carrying out the deployment is automatic in that it’s not a person manually running through a checklist or set of actions. The deployment still requires a single-click from a user. Actions: Get your environments set up and ready, Set access permissions appropriately, Make sure everyone understands what the environments will be used for (it’s not a “free-for-all” with all environments to be accessed, played with and changed by development). The Deployment Process As described earlier, most existing database deployment processes are pretty manual. The following is a description of a process we hear very often when we ask customers “How do your database changes get live? How does your manual process work?” Check pre-production matches production (use a schema compare tool, like SQL Compare). Sometimes done by taking a backup from production and restoring in to pre-prod, Again, use a schema compare tool to find the differences between the latest version of the database ready to go live (i.e. what the team have been developing). This generates a script, User (generally, the DBA), reviews the script. This often involves manually checking updates against a spreadsheet or similar, Run the script on pre-production, and check there are no errors (i.e. it upgrades pre-production to what you hoped), If all working, run the script on production.* * this assumes there’s no problem with production drifting away from pre-production in the interim time period (i.e. someone has hacked something in to the production box without going through the proper change management process). This difference could undermine the validity of your pre-production deployment test. Red Gate is currently working on a free tool to detect this problem – sign up here at www.sqllighthouse.com, if you’re interested in testing early versions. There are several variations on this process – some better, some much worse! How do you automate this? In particular, step 3 – surely you can’t automate a DBA checking through a script, that everything is in order!? The key point here is to plan what you want in your new deployment process. There are so many options. At one extreme, pure continuous deployment – whenever a dev checks something in to source control, the CI process runs (including extensive and thorough testing!), before the deployment process keys in and automatically deploys that change to the live box. Not for the faint hearted – and really not something we recommend. At the other extreme, you might be more comfortable with a semi-automated process – the pre-production/production matching process is automated (with an error thrown if these environments don’t match), followed by a manual intervention, allowing for script approval by the DBA. One he/she clicks “Okay, I’m happy for that to go live”, the latter stages automatically take the script through to live. And anything in between of course – and other variations. But we’d strongly recommended sitting down with a whiteboard and your team, and spending a couple of hours mapping out “What do we do now?”, “What do we actually want?”, “What will satisfy our needs for continuous delivery, but still maintaining some sort of continuous control over the process?” NB: Most of what we’re discussing here is about production deployments. It’s important to note that you will also need to map out a deployment process for earlier environments (for example QA). However, these are likely to be less onerous, and many customers opt for a much more automated process for these boxes. Actions: Sit down with your team and a whiteboard, and draw out the answers to the questions above for your production deployments – “What do we do now?”, “What do we actually want?”, “What will satisfy our needs for continuous delivery, but still maintaining some sort of continuous control over the process?” Repeat for earlier environments (QA and so on). Rollback and Recovery If only every deployment went according to plan! Unfortunately they don’t – and when things go wrong, you need a rollback or recovery plan for what you’re going to do in that situation. Once you move in to a more automated database deployment process, you’re far more likely to be deploying more frequently than before. No longer once every 6 months, maybe now once per week, or even daily. Hence the need for a quick rollback or recovery process becomes paramount, and should be planned for. NB: These are mainly scenarios for handling rollbacks after the transaction has been committed. If a failure is detected during the transaction, the whole transaction can just be rolled back, no problem. There are various options, which we’ll explore in subsequent articles, things like: Immediately restore from backup, Have a pre-tested rollback script (remembering that really this is a “roll-forward” script – there’s not really such a thing as a rollback script for a database!) Have fallback environments – for example, using a blue-green deployment pattern. Different options have pros and cons – some are easier to set up, some require more investment in infrastructure; and of course some work better than others (the key issue with using backups, is loss of the interim transaction data that has been added between the failed deployment and the restore). The best mechanism will be primarily dependent on how your application works and how much you need a cast-iron failsafe mechanism. Actions: Work out an appropriate rollback strategy based on how your application and business works, your appetite for investment and requirements for a completely failsafe process. Development Practices This is perhaps the more difficult area for people to tackle. The process by which you can deploy database updates is actually intrinsically linked with the patterns and practices used to develop that database and linked application. So you need to decide whether you want to implement some changes to the way your developers actually develop the database (particularly schema changes) to make the deployment process easier. A good example is the pattern “Branch by abstraction”. Explained nicely here, by Martin Fowler, this is a process that can be used to make significant database changes (e.g. splitting a table) in a step-wise manner so that you can always roll back, without data loss – by making incremental updates to the database backward compatible. Slides 103-108 of the following slidedeck, from Niek Bartholomeus explain the process: https://speakerdeck.com/niekbartho/orchestration-in-meatspace As these slides show, by making a significant schema change in multiple steps – where each step can be rolled back without any loss of new data – this affords the release team the opportunity to have zero-downtime deployments with considerably less stress (because if an increment goes wrong, they can roll back easily). There are plenty more great patterns that can be implemented – the book Refactoring Databases, by Scott Ambler and Pramod Sadalage is a great read, if this is a direction you want to go in: http://www.amazon.com/Refactoring-Databases-Evolutionary-paperback-Addison-Wesley/dp/0321774515 But the question is – how much of this investment are you willing to make? How often are you making significant schema changes that would require these best practices? Again, there’s a difference here between migrating old projects and starting afresh – with the latter it’s much easier to instigate best practice from the start. Actions: For your business, work out how far down the path you want to go, amending your database development patterns to “best practice”. It’s a trade-off between implementing quality processes, and the necessity to do so (depending on how often you make complex changes). Socialise these changes with your development group. No-one likes having “best practice” changes imposed on them, so good to introduce these ideas and the rationale behind them early.   Summary The next stages of implementing a continuous delivery pipeline for your database changes (once you have CI up and running) require a little pre-planning, if you want to get the most out of the work, and for the implementation to go smoothly. We’ve covered some of the checklist of areas to consider – mainly in the areas of “Getting the team ready for the changes that are coming” and “Planning our your pipeline, environments, patterns and practices for development”, though there will be more detail, depending on where you’re coming from – and where you want to get to. This article is part of our database delivery patterns & practices series on Simple Talk. Find more articles for version control, automated testing, continuous integration & deployment.

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• Microsoft Introduces WebMatrix

  - by Rick Strahl

  originally published in CoDe Magazine Editorial Microsoft recently released the first CTP of a new development environment called WebMatrix, which along with some of its supporting technologies are squarely aimed at making the Microsoft Web Platform more approachable for first-time developers and hobbyists. But in the process, it also provides some updated technologies that can make life easier for existing .NET developers. Let’s face it: ASP.NET development isn’t exactly trivial unless you already have a fair bit of familiarity with sophisticated development practices. Stick a non-developer in front of Visual Studio .NET or even the Visual Web Developer Express edition and it’s not likely that the person in front of the screen will be very productive or feel inspired. Yet other technologies like PHP and even classic ASP did provide the ability for non-developers and hobbyists to become reasonably proficient in creating basic web content quickly and efficiently. WebMatrix appears to be Microsoft’s attempt to bring back some of that simplicity with a number of technologies and tools. The key is to provide a friendly and fully self-contained development environment that provides all the tools needed to build an application in one place, as well as tools that allow publishing of content and databases easily to the web server. WebMatrix is made up of several components and technologies: IIS Developer Express IIS Developer Express is a new, self-contained development web server that is fully compatible with IIS 7.5 and based on the same codebase that IIS 7.5 uses. This new development server replaces the much less compatible Cassini web server that’s been used in Visual Studio and the Express editions. IIS Express addresses a few shortcomings of the Cassini server such as the inability to serve custom ISAPI extensions (i.e., things like PHP or ASP classic for example), as well as not supporting advanced authentication. IIS Developer Express provides most of the IIS 7.5 feature set providing much better compatibility between development and live deployment scenarios. SQL Server Compact 4.0 Database access is a key component for most web-driven applications, but on the Microsoft stack this has mostly meant you have to use SQL Server or SQL Server Express. SQL Server Compact is not new-it’s been around for a few years, but it’s been severely hobbled in the past by terrible tool support and the inability to support more than a single connection in Microsoft’s attempt to avoid losing SQL Server licensing. The new release of SQL Server Compact 4.0 supports multiple connections and you can run it in ASP.NET web applications simply by installing an assembly into the bin folder of the web application. In effect, you don’t have to install a special system configuration to run SQL Compact as it is a drop-in database engine: Copy the small assembly into your BIN folder (or from the GAC if installed fully), create a connection string against a local file-based database file, and then start firing SQL requests. Additionally WebMatrix includes nice tools to edit the database tables and files, along with tools to easily upsize (and hopefully downsize in the future) to full SQL Server. This is a big win, pending compatibility and performance limits. In my simple testing the data engine performed well enough for small data sets. This is not only useful for web applications, but also for desktop applications for which a fully installed SQL engine like SQL Server would be overkill. Having a local data store in those applications that can potentially be accessed by multiple users is a welcome feature. ASP.NET Razor View Engine What? Yet another native ASP.NET view engine? We already have Web Forms and various different flavors of using that view engine with Web Forms and MVC. Do we really need another? Microsoft thinks so, and Razor is an implementation of a lightweight, script-only view engine. Unlike the Web Forms view engine, Razor works only with inline code, snippets, and markup; therefore, it is more in line with current thinking of what a view engine should represent. There’s no support for a “page model” or any of the other Web Forms features of the full-page framework, but just a lightweight scripting engine that works with plain markup plus embedded expressions and code. The markup syntax for Razor is geared for minimal typing, plus some progressive detection of where a script block/expression starts and ends. This results in a much leaner syntax than the typical ASP.NET Web Forms alligator (<% %>) tags. Razor uses the @ sign plus standard C# (or Visual Basic) block syntax to delineate code snippets and expressions. Here’s a very simple example of what Razor markup looks like along with some comment annotations: <!DOCTYPE html> <html>     <head>         <title></title>     </head>     <body>     <h1>Razor Test</h1>          <!-- simple expressions -->     @DateTime.Now     <hr />     <!-- method expressions -->     @DateTime.Now.ToString("T")          <!-- code blocks -->     @{         List<string> names = new List<string>();         names.Add("Rick");         names.Add("Markus");         names.Add("Claudio");         names.Add("Kevin");     }          <!-- structured block statements -->     <ul>     @foreach(string name in names){             <li>@name</li>     }     </ul>           <!-- Conditional code -->        @if(true) {                        <!-- Literal Text embedding in code -->        <text>         true        </text>;    }    else    {        <!-- Literal Text embedding in code -->       <text>       false       </text>;    }    </body> </html> Like the Web Forms view engine, Razor parses pages into code, and then executes that run-time compiled code. Effectively a “page” becomes a code file with markup becoming literal text written into the Response stream, code snippets becoming raw code, and expressions being written out with Response.Write(). The code generated from Razor doesn’t look much different from similar Web Forms code that only uses script tags; so although the syntax may look different, the operational model is fairly similar to the Web Forms engine minus the overhead of the large Page object model. However, there are differences: -Razor pages are based on a new base class, Microsoft.WebPages.WebPage, which is hosted in the Microsoft.WebPages assembly that houses all the Razor engine parsing and processing logic. Browsing through the assembly (in the generated ASP.NET Temporary Files folder or GAC) will give you a good idea of the functionality that Razor provides. If you look closely, a lot of the feature set matches ASP.NET MVC’s view implementation as well as many of the helper classes found in MVC. It’s not hard to guess the motivation for this sort of view engine: For beginning developers the simple markup syntax is easier to work with, although you obviously still need to have some understanding of the .NET Framework in order to create dynamic content. The syntax is easier to read and grok and much shorter to type than ASP.NET alligator tags (<% %>) and also easier to understand aesthetically what’s happening in the markup code. Razor also is a better fit for Microsoft’s vision of ASP.NET MVC: It’s a new view engine without the baggage of Web Forms attached to it. The engine is more lightweight since it doesn’t carry all the features and object model of Web Forms with it and it can be instantiated directly outside of the HTTP environment, which has been rather tricky to do for the Web Forms view engine. Having a standalone script parser is a huge win for other applications as well – it makes it much easier to create script or meta driven output generators for many types of applications from code/screen generators, to simple form letters to data merging applications with user customizability. For me personally this is very useful side effect and who knows maybe Microsoft will actually standardize they’re scripting engines (die T4 die!) on this engine. Razor also better fits the “view-based” approach where the view is supposed to be mostly a visual representation that doesn’t hold much, if any, code. While you can still use code, the code you do write has to be self-contained. Overall I wouldn’t be surprised if Razor will become the new standard view engine for MVC in the future – and in fact there have been announcements recently that Razor will become the default script engine in ASP.NET MVC 3.0. Razor can also be used in existing Web Forms and MVC applications, although that’s not working currently unless you manually configure the script mappings and add the appropriate assemblies. It’s possible to do it, but it’s probably better to wait until Microsoft releases official support for Razor scripts in Visual Studio. Once that happens, you can simply drop .cshtml and .vbhtml pages into an existing ASP.NET project and they will work side by side with classic ASP.NET pages. WebMatrix Development Environment To tie all of these three technologies together, Microsoft is shipping WebMatrix with an integrated development environment. An integrated gallery manager makes it easy to download and load existing projects, and then extend them with custom functionality. It seems to be a prominent goal to provide community-oriented content that can act as a starting point, be it via a custom templates or a complete standard application. The IDE includes a project manager that works with a single project and provides an integrated IDE/editor for editing the .cshtml and .vbhtml pages. A run button allows you to quickly run pages in the project manager in a variety of browsers. There’s no debugging support for code at this time. Note that Razor pages don’t require explicit compilation, so making a change, saving, and then refreshing your page in the browser is all that’s needed to see changes while testing an application locally. It’s essentially using the auto-compiling Web Project that was introduced with .NET 2.0. All code is compiled during run time into dynamically created assemblies in the ASP.NET temp folder. WebMatrix also has PHP Editing support with syntax highlighting. You can load various PHP-based applications from the WebMatrix Web Gallery directly into the IDE. Most of the Web Gallery applications are ready to install and run without further configuration, with Wizards taking you through installation of tools, dependencies, and configuration of the database as needed. WebMatrix leverages the Web Platform installer to pull the pieces down from websites in a tight integration of tools that worked nicely for the four or five applications I tried this out on. Click a couple of check boxes and fill in a few simple configuration options and you end up with a running application that’s ready to be customized. Nice! You can easily deploy completed applications via WebDeploy (to an IIS server) or FTP directly from within the development environment. The deploy tool also can handle automatically uploading and installing the database and all related assemblies required, making deployment a simple one-click install step. Simplified Database Access The IDE contains a database editor that can edit SQL Compact and SQL Server databases. There is also a Database helper class that facilitates database access by providing easy-to-use, high-level query execution and iteration methods: @{       var db = Database.OpenFile("FirstApp.sdf");     string sql = "select * from customers where Id > @0"; } <ul> @foreach(var row in db.Query(sql,1)){         <li>@row.FirstName @row.LastName</li> } </ul> The query function takes a SQL statement plus any number of positional (@0,@1 etc.) SQL parameters by simple values. The result is returned as a collection of rows which in turn have a row object with dynamic properties for each of the columns giving easy (though untyped) access to each of the fields. Likewise Execute and ExecuteNonQuery allow execution of more complex queries using similar parameter passing schemes. Note these queries use string-based queries rather than LINQ or Entity Framework’s strongly typed LINQ queries. While this may seem like a step back, it’s also in line with the expectations of non .NET script developers who are quite used to writing and using SQL strings in code rather than using OR/M frameworks. The only question is why was something not included from the beginning in .NET and Microsoft made developers build custom implementations of these basic building blocks. The implementation looks a lot like a DataTable-style data access mechanism, but to be fair, this is a common approach in scripting languages. This type of syntax that uses simple, static, data object methods to perform simple data tasks with one line of code are common in scripting languages and are a good match for folks working in PHP/Python, etc. Seems like Microsoft has taken great advantage of .NET 4.0’s dynamic typing to provide this sort of interface for row iteration where each row has properties for each field. FWIW, all the examples demonstrate using local SQL Compact files - I was unable to get a SQL Server connection string to work with the Database class (the connection string wasn’t accepted). However, since the code in the page is still plain old .NET, you can easily use standard ADO.NET code or even LINQ or Entity Framework models that are created outside of WebMatrix in separate assemblies as required. The good the bad the obnoxious - It’s still .NET The beauty (or curse depending on how you look at it :)) of Razor and the compilation model is that, behind it all, it’s still .NET. Although the syntax may look foreign, it’s still all .NET behind the scenes. You can easily access existing tools, helpers, and utilities simply by adding them to the project as references or to the bin folder. Razor automatically recognizes any assembly reference from assemblies in the bin folder. In the default configuration, Microsoft provides a host of helper functions in a Microsoft.WebPages assembly (check it out in the ASP.NET temp folder for your application), which includes a host of HTML Helpers. If you’ve used ASP.NET MVC before, a lot of the helpers should look familiar. Documentation at the moment is sketchy-there’s a very rough API reference you can check out here: http://www.asp.net/webmatrix/tutorials/asp-net-web-pages-api-reference Who needs WebMatrix? Uhm… good Question Clearly Microsoft is trying hard to create an environment with WebMatrix that is easy to use for newbie developers. The goal seems to be simplicity in providing a minimal development environment and an easy-to-use script engine/language that makes it easy to get started with. There’s also some focus on community features that can be used as starting points, such as Web Gallery applications and templates. The community features in particular are very nice and something that would be nice to eventually see in Visual Studio as well. The question is whether this is too little too late. Developers who have been clamoring for a simpler development environment on the .NET stack have mostly left for other simpler platforms like PHP or Python which are catering to the down and dirty developer. Microsoft will be hard pressed to win those folks-and other hardcore PHP developers-back. Regardless of how much you dress up a script engine fronted by the .NET Framework, it’s still the .NET Framework and all the complexity that drives it. While .NET is a fine solution in its breadth and features once you get a basic handle on the core features, the bar of entry to being productive with the .NET Framework is still pretty high. The MVC style helpers Microsoft provides are a good step in the right direction, but I suspect it’s not enough to shield new developers from having to delve much deeper into the Framework to get even basic applications built. Razor and its helpers is trying to make .NET more accessible but the reality is that in order to do useful stuff that goes beyond the handful of simple helpers you still are going to have to write some C# or VB or other .NET code. If the target is a hobby/amateur/non-programmer the learning curve isn’t made any easier by WebMatrix it’s just been shifted a tad bit further along in your development endeavor when you run out of canned components that are supplied either by Microsoft or the community. The database helpers are interesting and actually I’ve heard a lot of discussion from various developers who’ve been resisting .NET for a really long time perking up at the prospect of easier data access in .NET than the ridiculous amount of code it takes to do even simple data access with raw ADO.NET. It seems sad that such a simple concept and implementation should trigger this sort of response (especially since it’s practically trivial to create helpers like these or pick them up from countless libraries available), but there it is. It also shows that there are plenty of developers out there who are more interested in ‘getting stuff done’ easily than necessarily following the latest and greatest practices which are overkill for many development scenarios. Sometimes it seems that all of .NET is focused on the big life changing issues of development, rather than the bread and butter scenarios that many developers are interested in to get their work accomplished. And that in the end may be WebMatrix’s main raison d'être: To bring some focus back at Microsoft that simpler and more high level solutions are actually needed to appeal to the non-high end developers as well as providing the necessary tools for the high end developers who want to follow the latest and greatest trends. The current version of WebMatrix hits many sweet spots, but it also feels like it has a long way to go before it really can be a tool that a beginning developer or an accomplished developer can feel comfortable with. Although there are some really good ideas in the environment (like the gallery for downloading apps and components) which would be a great addition for Visual Studio as well, the rest of the development environment just feels like crippleware with required functionality missing especially debugging and Intellisense, but also general editor support. It’s not clear whether these are because the product is still in an early alpha release or whether it’s simply designed that way to be a really limited development environment. While simple can be good, nobody wants to feel left out when it comes to necessary tool support and WebMatrix just has that left out feeling to it. If anything WebMatrix’s technology pieces (which are really independent of the WebMatrix product) are what are interesting to developers in general. The compact IIS implementation is a nice improvement for development scenarios and SQL Compact 4.0 seems to address a lot of concerns that people have had and have complained about for some time with previous SQL Compact implementations. By far the most interesting and useful technology though seems to be the Razor view engine for its light weight implementation and it’s decoupling from the ASP.NET/HTTP pipeline to provide a standalone scripting/view engine that is pluggable. The first winner of this is going to be ASP.NET MVC which can now have a cleaner view model that isn’t inconsistent due to the baggage of non-implemented WebForms features that don’t work in MVC. But I expect that Razor will end up in many other applications as a scripting and code generation engine eventually. Visual Studio integration for Razor is currently missing, but is promised for a later release. The ASP.NET MVC team has already mentioned that Razor will eventually become the default MVC view engine, which will guarantee continued growth and development of this tool along those lines. And the Razor engine and support tools actually inherit many of the features that MVC pioneered, so there’s some synergy flowing both ways between Razor and MVC. As an existing ASP.NET developer who’s already familiar with Visual Studio and ASP.NET development, the WebMatrix IDE doesn’t give you anything that you want. The tools provided are minimal and provide nothing that you can’t get in Visual Studio today, except the minimal Razor syntax highlighting, so there’s little need to take a step back. With Visual Studio integration coming later there’s little reason to look at WebMatrix for tooling. It’s good to see that Microsoft is giving some thought about the ease of use of .NET as a platform For so many years, we’ve been piling on more and more new features without trying to take a step back and see how complicated the development/configuration/deployment process has become. Sometimes it’s good to take a step - or several steps - back and take another look and realize just how far we’ve come. WebMatrix is one of those reminders and one that likely will result in some positive changes on the platform as a whole. © Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET   IIS7  

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• After connecting wlan0 to bridge interface (and then removing it), can't connect to AP

  - by gmonk

  I'm on a laptop running Debian Jessie with kernel 3.13-1-amd64; lspci shows that my wireless NIC + driver is 04:00.0 Network controller: Intel Corporation Wireless 3160 (rev 83) Subsystem: Intel Corporation Dual Band Wireless-AC 3160 Kernel driver in use: iwlwifi This has been working without any problems, until I tried creating a bridge for lxc containers to use. I did the same thing as this person here: How-to set up a network bridge on a laptop for LXC use? -- and ended up having the same problem as this poster did, so I decided to "undo" my actions. This hasn't been successful. Actions taken so far: To configure the bridge: #> ip link add type veth #> iw dev wlan0 set 4addr on #> ifconfig veth0 up #> brctl addbr br0 #> brctl addif br0 wlan0 #> brctl addif br0 veth0 #> ifconfig br0 192.168.0.4/24 #> ifconfig wlan0 0.0.0.0 To "deconfigure": #> brctl delif br0 wlan0 #> brctl delif br0 veth0 #> iw dev wlan0 set 4addr off #> ifconfig veth0 down #> ifconfig wlan0 down #> ifconfig br0 down #> brctl delbr br0 Now, dmesg and /var/log/syslog show repeated attempts at connecting to the AP that was working before, which fail after authentication: May 27 09:16:01 myhostname kernel: [11350.757172] wlan0: authenticate with 00:18:f8:54:a3:d6 May 27 09:16:01 myhostname kernel: [11350.759036] wlan0: send auth to 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:01 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: scanning -> authenticating May 27 09:16:01 myhostname wpa_supplicant[8946]: wlan0: Trying to associate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:01 myhostname kernel: [11350.762615] wlan0: authenticated May 27 09:16:01 myhostname kernel: [11350.762753] iwlwifi 0000:04:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP May 27 09:16:01 myhostname kernel: [11350.762755] iwlwifi 0000:04:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP May 27 09:16:01 myhostname kernel: [11350.765080] wlan0: associate with 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:01 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: authenticating -> associating May 27 09:16:01 myhostname kernel: [11350.767474] wlan0: RX AssocResp from 00:18:f8:54:a3:d6 (capab=0x411 status=12 aid=0) May 27 09:16:01 myhostname kernel: [11350.767476] wlan0: 00:18:f8:54:a3:d6 denied association (code=12) May 27 09:16:01 myhostname wpa_supplicant[8946]: wlan0: CTRL-EVENT-ASSOC-REJECT bssid=00:18:f8:54:a3:d6 status_code=12 May 27 09:16:01 myhostname kernel: [11350.788475] wlan0: deauthenticating from 00:18:f8:54:a3:d6 by local choice (reason=3) May 27 09:16:01 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: associating -> disconnected May 27 09:16:01 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: disconnected -> scanning May 27 09:16:02 myhostname dhclient: DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 14 May 27 09:16:04 myhostname wpa_supplicant[8946]: wlan0: SME: Trying to authenticate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:04 myhostname kernel: [11354.559579] wlan0: authenticate with 00:18:f8:54:a3:d6 May 27 09:16:04 myhostname kernel: [11354.561458] wlan0: send auth to 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:04 myhostname wpa_supplicant[8946]: wlan0: Trying to associate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:04 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: scanning -> associating May 27 09:16:04 myhostname kernel: [11354.563445] wlan0: authenticated May 27 09:16:04 myhostname kernel: [11354.563631] iwlwifi 0000:04:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP May 27 09:16:04 myhostname kernel: [11354.563633] iwlwifi 0000:04:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP May 27 09:16:04 myhostname kernel: [11354.565727] wlan0: associate with 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:04 myhostname wpa_supplicant[8946]: wlan0: Associated with 00:18:f8:54:a3:d6 May 27 09:16:04 myhostname kernel: [11354.568091] wlan0: RX AssocResp from 00:18:f8:54:a3:d6 (capab=0x411 status=0 aid=9) May 27 09:16:04 myhostname kernel: [11354.569030] wlan0: associated May 27 09:16:04 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: associating -> associated May 27 09:16:05 myhostname kernel: [11354.978204] wlan0: deauthenticated from 00:18:f8:54:a3:d6 (Reason: 15) May 27 09:16:05 myhostname wpa_supplicant[8946]: wlan0: CTRL-EVENT-DISCONNECTED bssid=00:18:f8:54:a3:d6 reason=15 May 27 09:16:05 myhostname kernel: [11354.992729] cfg80211: Calling CRDA to update world regulatory domain May 27 09:16:05 myhostname kernel: [11354.995004] cfg80211: World regulatory domain updated: May 27 09:16:05 myhostname kernel: [11354.995005] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp) May 27 09:16:05 myhostname kernel: [11354.995006] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (N/A, 2000 mBm) May 27 09:16:05 myhostname kernel: [11354.995007] cfg80211: (2457000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm) May 27 09:16:05 myhostname kernel: [11354.995007] cfg80211: (2474000 KHz - 2494000 KHz @ 20000 KHz), (N/A, 2000 mBm) May 27 09:16:05 myhostname kernel: [11354.995008] cfg80211: (5170000 KHz - 5250000 KHz @ 80000 KHz), (N/A, 2000 mBm) May 27 09:16:05 myhostname kernel: [11354.995009] cfg80211: (5735000 KHz - 5835000 KHz @ 80000 KHz), (N/A, 2000 mBm) May 27 09:16:05 myhostname kernel: [11354.995010] cfg80211: (57240000 KHz - 63720000 KHz @ 2160000 KHz), (N/A, 0 mBm) May 27 09:16:05 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: associated -> disconnected May 27 09:16:05 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: disconnected -> scanning May 27 09:16:09 myhostname wpa_supplicant[8946]: wlan0: SME: Trying to authenticate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:09 myhostname kernel: [11358.763968] wlan0: authenticate with 00:18:f8:54:a3:d6 May 27 09:16:09 myhostname kernel: [11358.765796] wlan0: send auth to 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:09 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: scanning -> authenticating May 27 09:16:09 myhostname wpa_supplicant[8946]: wlan0: Trying to associate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:09 myhostname kernel: [11358.769957] wlan0: authenticated May 27 09:16:09 myhostname kernel: [11358.770102] iwlwifi 0000:04:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP May 27 09:16:09 myhostname kernel: [11358.770104] iwlwifi 0000:04:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP May 27 09:16:09 myhostname kernel: [11358.770846] wlan0: associate with 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:09 myhostname kernel: [11358.773358] wlan0: RX AssocResp from 00:18:f8:54:a3:d6 (capab=0x411 status=12 aid=0) May 27 09:16:09 myhostname kernel: [11358.773361] wlan0: 00:18:f8:54:a3:d6 denied association (code=12) May 27 09:16:09 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: authenticating -> associating May 27 09:16:09 myhostname wpa_supplicant[8946]: wlan0: CTRL-EVENT-ASSOC-REJECT bssid=00:18:f8:54:a3:d6 status_code=12 May 27 09:16:09 myhostname kernel: [11358.802187] wlan0: deauthenticating from 00:18:f8:54:a3:d6 by local choice (reason=3) May 27 09:16:09 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: associating -> disconnected May 27 09:16:09 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: disconnected -> scanning May 27 09:16:12 myhostname wpa_supplicant[8946]: wlan0: SME: Trying to authenticate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:12 myhostname kernel: [11362.573442] wlan0: authenticate with 00:18:f8:54:a3:d6 May 27 09:16:12 myhostname kernel: [11362.575270] wlan0: send auth to 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:12 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: scanning -> authenticating May 27 09:16:12 myhostname wpa_supplicant[8946]: wlan0: Trying to associate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:12 myhostname kernel: [11362.580334] wlan0: authenticated May 27 09:16:12 myhostname kernel: [11362.580503] iwlwifi 0000:04:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP May 27 09:16:12 myhostname kernel: [11362.580516] iwlwifi 0000:04:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP May 27 09:16:12 myhostname kernel: [11362.583508] wlan0: associate with 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:12 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: authenticating -> associating May 27 09:16:12 myhostname wpa_supplicant[8946]: wlan0: Associated with 00:18:f8:54:a3:d6 May 27 09:16:12 myhostname kernel: [11362.585908] wlan0: RX AssocResp from 00:18:f8:54:a3:d6 (capab=0x411 status=0 aid=9) May 27 09:16:12 myhostname kernel: [11362.586781] wlan0: associated May 27 09:16:12 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: associating -> associated May 27 09:16:13 myhostname kernel: [11362.947693] wlan0: deauthenticated from 00:18:f8:54:a3:d6 (Reason: 15) May 27 09:16:13 myhostname wpa_supplicant[8946]: wlan0: CTRL-EVENT-DISCONNECTED bssid=00:18:f8:54:a3:d6 reason=15 May 27 09:16:13 myhostname kernel: [11362.973461] cfg80211: Calling CRDA to update world regulatory domain May 27 09:16:13 myhostname kernel: [11362.975673] cfg80211: World regulatory domain updated: May 27 09:16:13 myhostname kernel: [11362.975675] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp) May 27 09:16:13 myhostname kernel: [11362.975676] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (N/A, 2000 mBm) May 27 09:16:13 myhostname kernel: [11362.975677] cfg80211: (2457000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm) May 27 09:16:13 myhostname kernel: [11362.975678] cfg80211: (2474000 KHz - 2494000 KHz @ 20000 KHz), (N/A, 2000 mBm) May 27 09:16:13 myhostname kernel: [11362.975678] cfg80211: (5170000 KHz - 5250000 KHz @ 80000 KHz), (N/A, 2000 mBm) May 27 09:16:13 myhostname kernel: [11362.975679] cfg80211: (5735000 KHz - 5835000 KHz @ 80000 KHz), (N/A, 2000 mBm) May 27 09:16:13 myhostname kernel: [11362.975679] cfg80211: (57240000 KHz - 63720000 KHz @ 2160000 KHz), (N/A, 0 mBm) May 27 09:16:13 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: associated -> disconnected May 27 09:16:13 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: disconnected -> scanning May 27 09:16:14 myhostname NetworkManager[13992]: <warn> Activation (wlan0/wireless): association took too long. May 27 09:16:14 myhostname NetworkManager[13992]: <info> (wlan0): device state change: config -> failed (reason 'no-secrets') [50 120 7] May 27 09:16:14 myhostname NetworkManager[13992]: <info> Marking connection 'Auto myaccesspoint' invalid. May 27 09:16:14 myhostname NetworkManager[13992]: <warn> Activation (wlan0) failed for connection 'Auto myaccesspoint' May 27 09:16:14 myhostname NetworkManager[13992]: <info> (wlan0): device state change: failed -> disconnected (reason 'none') [120 30 0] May 27 09:16:14 myhostname NetworkManager[13992]: <info> (wlan0): deactivating device (reason 'none') [0] May 27 09:16:14 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: scanning -> disconnected The things that jump out at me are "deauthenticating ... by local choice( reason=3)" and the lines that contain "(reason=15)". I've tried various fixes: iwconfig wlan0 power off killing wpa_supplicant connecting with iwconfig + dhclient instead of gnome's network -manager explicitly configuring wlan0 in /etc/network/interfaces creating a /etc/wpa_supplicant.conf file ...but nothing seems to work. I'm not sure what I did wrong, or what step I've skipped in trying to get wlan0 back as a non-bridged device -- I removed it from the bridge and then deleted the bridge itself. Any ideas?

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• Need help with workflow in Alfresco

  - by Scott Gartner

  Hello SO community, I haven't had any luck getting help in the Alfresco forums, and I'm hoping for more here. We are building an application based on Alfresco and jBPM and I have defined a workflow, but I have either defined it wrong or am missing something or there are bugs in Alfresco integration with jBPM and I need help figuring out which and fixing it. Here is the problem: I have an advanced workflow and I am trying to launch it from JavaScript. Here is the code I'm using to start the workflow: var nodeId = args.nodeid; var document = search.findNode("workspace://SpacesStore/" + nodeId); var workflowAction = actions.create("start-workflow"); workflowAction.parameters.workflowName = "jbpm$nmwf:MyWorkflow"; workflowAction.parameters["bpm:workflowDescription"] = "Please edit: " + document.name; workflowAction.parameters["bpm:assignees"] = [people.getPerson("admin"), people.getPerson("andyg")]; var futureDate = new Date(); futureDate.setDate(futureDate.getDate() + 7); workflowAction.parameters["bpm:workflowDueDate"] = futureDate; workflowAction.execute(document); This runs fine and e-mail sent from the start node's default transition fires just fine. However, when I go looking for the workflow in my task list it is not there, but it is in my completed task list. The default transition (the only transition) from the start node points at a task node which has four transitions. There are 8 tasks and 22 transitions in the workflow. When I use the workflow console to start the workflow and end the start task, it properly follows the default start node transition to the next task. The new task shows up in "show tasks" but does not show up in "show my tasks" (apparently because the task was marked completed for some reason, though it is not in the "end" node). The task is: task id: jbpm$111 , name: nmwf:submitInEditing , properties: 18 If I do "show transitions" it looks just as I would expect: path: jbpm$62-@ , node: In Editing , active: true task id: jbpm$111 , name: nmwf:submitInEditing, title: submitInEditing title , desc: submitInEditing description , properties: 18 transition id: Submit for Approval , title: Submit for Approval transition id: Request Copyediting Review , title: Request Copyediting Review transition id: Request Legal Review , title: Request Legal Review transition id: Request Review , title: Request Review I don't want to post the entire workflow as it's large, but here are the first two nodes: First the swimlanes: <swimlane name="initiator"></swimlane> <swimlane name="Content Providers"> <assignment actor-id="Content Providers"> <actor>#{bpm_assignees}</actor> </assignment> </swimlane> Now the nodes: <start-state name="start"> <task name="nmwf:submitTask" swimlane="initiator"/> <transition name="" to="In Editing"> <action> <runas>admin</runas> <script> /* Code to send e-mail that a new workflow was started. I get this e-mail. */ </script> </action> </transition> </start-state> <task-node name="In Editing"> <task name="nmwf:submitInEditing" swimlane="Content Providers" /> <!-- I put e-mail sending code in each of these transitions, but none are firing. --> <transition to="In Approval" name="Submit for Approval"></transition> <transition to="In Copyediting" name="Request Copyediting Review"></transition> <transition to="In Legal Review" name="Request Legal Review"></transition> <transition to="In Review" name="Request Review"></transition> </task-node> Here is the model for these two nodes: <type name="nmwf:submitTask"> <parent>bpm:startTask</parent> <mandatory-aspects> <aspect>bpm:assignees</aspect> </mandatory-aspects> </type> <type name="nmwf:submitInEditing"> <parent>bpm:workflowTask</parent> <mandatory-aspects> <aspect>bpm:assignees</aspect> </mandatory-aspects> </type> Here is a pseudo-log of running the workflow in the workflow console: :: deploy alfresco/extension/workflow/processdefinition.xml deployed definition id: jbpm$69 , name: jbpm$nmwf:MyWorkflow , title: nmwf:MyWorkflow , version: 28 :: var bpm:assignees* person admin,andyg set var {http://www.alfresco.org/model/bpm/1.0}assignees = [workspace://SpacesStore/73cf1b28-21aa-40ca-9dde-1cff492d0268, workspace://SpacesStore/03297e91-0b89-4db6-b764-5ada2d167424] :: var bpm:package package 1 set var {http://www.alfresco.org/model/bpm/1.0}package = workspace://SpacesStore/6e2bbbbd-b728-4403-be37-dfce55a83641 :: start bpm:assignees bpm:package started workflow id: jbpm$63 , def: nmwf:MyWorkflow path: jbpm$63-@ , node: start , active: true task id: jbpm$112 , name: nmwf:submitTask, title: submitTask title , desc: submitTask description , properties: 16 transition id: [default] , title: Task Done :: show transitions path: jbpm$63-@ , node: start , active: true task id: jbpm$112 , name: nmwf:submitTask, title: submitTask title , desc: submitTask description , properties: 17 transition id: [default] , title: Task Done :: end task jbpm$112 signal sent - path id: jbpm$63-@ path: jbpm$63-@ , node: In Editing , active: true task id: jbpm$113 , name: nmwf:submitInEditing, title: submitInEditing title , desc: submitInEditing description , properties: 17 transition id: Submit for Approval , title: Submit for Approval transition id: Request Copyediting Review , title: Request Copyediting Review transition id: Request Legal Review , title: Request Legal Review transition id: Request Review , title: Request Review :: show tasks task id: jbpm$113 , name: nmwf:submitInEditing , properties: 18 :: show my tasks admin: [there is no output here] I have been making the assumption that the bpm:assignees that I am setting before starting the workflow initially are getting passed to the first task node "In Editing". Clearly the assignees are on the task object and not on the workflow object. I added the assignees aspect to the start-state task so that it could hold them (after I had a problem; initially they were not there) and possibly they are still sitting there, but the start-state has ended before I even get control back from the web script (not that it would help if it wasn't ended, I need it to be in "In Editing" as the start-state is only used to log that the workflow was started). It has always confused me that the properties that I need to set on each task need to be requested before the task is entered (when you choose a transition you must provide the data for the next task before you can actually move to the next task as you have to validate that you have all of the required data first and then signal the transition). However, the code to start the workflow is asynchronous and therefore does not return either the started workflow or the current task (which in my case would be "In Editing"). So, either way you cannot set variables such as bpm:assignees and bpm:dueDate. I wonder if this is the problem with the user task list. I'm setting the assignees in the property list, but maybe those assignees are going to the start-state task and are not getting passed to the "In Editing" task? Note that this is my first jBPM workflow, so please don't assume I know what I'm doing. If you see something that looks off, it probably is and I just don't know it. Thanks in advance for any advice or help,

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• Simplemodal: four times on a page leads to extra "next" or "previous" button

  - by DDF

  We are experiencing a problem with each instance of the call to the simplemodal div class .basic-modal-content adding an extra next or previous button in the modal windows. We are using simplemodal in four places on a page using a common JS in the container (provided below) and a common CSS format for the modal windows. In one area we are using six "statements" in a window with a next and previous button. I would include a picture of the modal window but it's being disallowed by the system as I'm a first time poster to this forum. In the other three areas we are using three "biographies" in a similar window with the ability to see each of the three bios from each of modal windows. We are using a common Simplemodal JS script in the page which has the following code: <script> $(function() { $('a').each(function() { $(this).click(function() { $('#modal_' + this.id).modal({ overlayClose:true }); }); }); var num_divs = $('div.basic-modal-content').length; $('div.basic-modal-content').each(function(i) { /* if there is a previous div add a link to it */ if (i > 0) { /* get the ID for previous div */ var prev_id = $(this).prev('.basic-modal-content').attr('id'); /* add the link with click event */ $('<a href="#" class="simplemodal-container-prev"></a>') .click(function() { $.modal.close(); $('#' + prev_id).modal({overlayClose:true}); }) .appendTo($(this)); } /* if there is a next div add a link to it */ if (i < num_divs - 1) { /* get the ID for next div */ var next_id = $(this).next('.basic-modal-content').attr('id'); /* add the link with click event */ $('<a href="#" class="simplemodal-container-next"></a>') .click(function() { $.modal.close(); $('#' + next_id).modal({overlayClose:true}); }) .appendTo($(this)); } }); }); </script> and some CSS to create an image for each window that shows the progress bar through the ul/li list. The code to produce the above looks like this: <h1>Our HEADLINE</h1> <div id='basic-modal'> <ul> <li><a href='#' id='one'>TEXT 1</a></li> <li><a href='#' id='two'>TEXT 2</a></li> <li><a href='#' id='three'>TEXT 3</a></li> <li><a href='#' id='four'>TEXT 4</a></li> <li><a href='#' id='five'>TEXT 5</a></li> <li><a href='#' id='six'>TEXT 6</a></li> </ul> </div> <div class="basic-modal-content" id="modal_one"> <img src="link to modal_one.png" alt="progress bar"/> <h3>headline text</h3> <p>body text</p> </div> <div class="basic-modal-content" id="modal_two"> <img src="link to modal_two.png" alt="progress bar"/> <h3>headline text</h3> <p>body text</p> </div> <div> ... other divs 3 4 and 5 </div> <div class="basic-modal-content" id="modal_six"> <img src="link to modal_six.png" alt="progress bar"/> <h3>headline text</h3> <p>body text</p> </div> </div> The ul/li structure works on the main page for the links. The modal windows allow one to browse through all of the six TEXTs. There is a common CSS style to the windows and a custom image in each of the modal windows derived from the "#modal_[number] img" CSS in the form of a progress bar. It should be noted that the first modal window in the first set of ul/li (the six) do not exhibit the extra previous button. Here is the relevant code from one of the three biographic links. You will note that the biographic links each have to have all three in this current configuration. <h4>Our HEADLINE</h4> <div class="bottom-widget-text"> <img src="picture" alt="not relevant to the simplemodal problem"/> <p>Read about person NUMBER 1 by clicking on the following link: <a href='#' id='seven' >Expand</a> </p> </div> <div class="basic-modal-content" id="modal_seven"> <img src="link to modal_seven.png" alt="portrait 1"/> <h3>headline text</h3> <p>BIOGRAPHY</p> </div> <div class="basic-modal-content" id="modal_eight"> <img src="link to modal_eight.png" alt="portrait 2"/> <h3>headline text</h3> <p>BIOGRAPHY</p> </div> <div class="basic-modal-content" id="modal_nine"> <img src="link to modal_nine.png" alt="portrait 3"/> <h3>headline text</h3> <p>BIOGRAPHY</p> </div> </div> Similarly the "biographies" open up from a different area of the page. The modal windows allow one to browse through all three of the BIOs. The bios use the SAME CSS style windows and a custom image in each of the modal windows derived from the "#modal_[number] img" CSS in the form of a portrait. Everything is working well except one thing: the first six windows have an extra next button that leads to an image of the close widow button only. Similarly, the BIOs pages have extra previous button that leads to the same "close button only" shown above. We want to maintain the same base CSS for the modal windows for this page. We want to keep the JS simple. The only behavior that is bad is the extra previous and next bottons that appear to be spurious. So is this a fix to the JS? Or do I have the instances of the modal windows too entangled? Perhaps there is a better method for having multiple instances of a simplemodal window on the same page? Or is the problem the "#" variable being common to each of the uses of the JS? Thanks in advance. DDF

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• Optimizing a lot of Scanner.findWithinHorizon(pattern, 0) calls

  - by darvids0n

  I'm building a process which extracts data from 6 csv-style files and two poorly laid out .txt reports and builds output CSVs, and I'm fully aware that there's going to be some overhead searching through all that whitespace thousands of times, but I never anticipated converting about about 50,000 records would take 12 hours. Excerpt of my manual matching code (I know it's horrible that I use lists of tokens like that, but it was the best thing I could think of): public static String lookup(List<String> tokensBefore, List<String> tokensAfter) { String result = null; while(_match(tokensBefore)) { // block until all input is read if(id.hasNext()) { result = id.next(); // capture the next token that matches if(_matchImmediate(tokensAfter)) // try to match tokensAfter to this result return result; } else return null; // end of file; no match } return null; // no matches } private static boolean _match(List<String> tokens) { return _match(tokens, true); } private static boolean _match(List<String> tokens, boolean block) { if(tokens != null && !tokens.isEmpty()) { if(id.findWithinHorizon(tokens.get(0), 0) == null) return false; for(int i = 1; i <= tokens.size(); i++) { if (i == tokens.size()) { // matches all tokens return true; } else if(id.hasNext() && !id.next().matches(tokens.get(i))) { break; // break to blocking behaviour } } } else { return true; // empty list always matches } if(block) return _match(tokens); // loop until we find something or nothing else return false; // return after just one attempted match } private static boolean _matchImmediate(List<String> tokens) { if(tokens != null) { for(int i = 0; i <= tokens.size(); i++) { if (i == tokens.size()) { // matches all tokens return true; } else if(!id.hasNext() || !id.next().matches(tokens.get(i))) { return false; // doesn't match, or end of file } } return false; // we have some serious problems if this ever gets called } else { return true; // empty list always matches } } Basically wondering how I would work in an efficient string search (Boyer-Moore or similar). My Scanner id is scanning a java.util.String, figured buffering it to memory would reduce I/O since the search here is being performed thousands of times on a relatively small file. The performance increase compared to scanning a BufferedReader(FileReader(File)) was probably less than 1%, the process still looks to be taking a LONG time. I've also traced execution and the slowness of my overall conversion process is definitely between the first and last like of the lookup method. In fact, so much so that I ran a shortcut process to count the number of occurrences of various identifiers in the .csv-style files (I use 2 lookup methods, this is just one of them) and the process completed indexing approx 4 different identifiers for 50,000 records in less than a minute. Compared to 12 hours, that's instant. Some notes (updated): I don't necessarily need the pattern-matching behaviour, I only get the first field of a line of text so I need to match line breaks or use Scanner.nextLine(). All ID numbers I need start at position 0 of a line and run through til the first block of whitespace, after which is the name of the corresponding object. I would ideally want to return a String, not an int locating the line number or start position of the result, but if it's faster then it will still work just fine. If an int is being returned, however, then I would now have to seek to that line again just to get the ID; storing the ID of every line that is searched sounds like a way around that. Anything to help me out, even if it saves 1ms per search, will help, so all input is appreciated. Thankyou! Usage scenario 1: I have a list of objects in file A, who in the old-style system have an id number which is not in file A. It is, however, POSSIBLY in another csv-style file (file B) or possibly still in a .txt report (file C) which each also contain a bunch of other information which is not useful here, and so file B needs to be searched through for the object's full name (1 token since it would reside within the second column of any given line), and then the first column should be the ID number. If that doesn't work, we then have to split the search token by whitespace into separate tokens before doing a search of file C for those tokens as well. Generalised code: String field; for (/* each record in file A */) { /* construct the rest of this object from file A info */ // now to find the ID, if we can List<String> objectName = new ArrayList<String>(1); objectName.add(Pattern.quote(thisObject.fullName)); field = lookup(objectSearchToken, objectName); // search file B if(field == null) // not found in file B { lookupReset(false); // initialise scanner to check file C objectName.clear(); // not using the full name String[] tokens = thisObject.fullName.split(id.delimiter().pattern()); for(String s : tokens) objectName.add(Pattern.quote(s)); field = lookup(objectSearchToken, objectName); // search file C lookupReset(true); // back to file B } else { /* found it, file B specific processing here */ } if(field != null) // found it in B or C thisObject.ID = field; } The objectName tokens are all uppercase words with possible hyphens or apostrophes in them, separated by spaces. Much like a person's name. As per a comment, I will pre-compile the regex for my objectSearchToken, which is just [\r\n]+. What's ending up happening in file C is, every single line is being checked, even the 95% of lines which don't contain an ID number and object name at the start. Would it be quicker to use ^[\r\n]+.*(objectname) instead of two separate regexes? It may reduce the number of _match executions. The more general case of that would be, concatenate all tokensBefore with all tokensAfter, and put a .* in the middle. It would need to be matching backwards through the file though, otherwise it would match the correct line but with a huge .* block in the middle with lots of lines. The above situation could be resolved if I could get java.util.Scanner to return the token previous to the current one after a call to findWithinHorizon. I have another usage scenario. Will put it up asap.

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• org.hibernate.MappingException: Unknown entity:

  - by tsegay

  I tried to see all the questions on this topic but none of them helped me. And I really want to understand what is going on with my code. I have a standalone application which uses spring and Hibernate as JPA and I am trying to run the test using a single main Class My main class package edu.acct.tsegay.common; import edu.acct.tsegay.model.User; import edu.acct.tsegay.business.IUserBusinessObject; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; public class App { public static void main(String[] args) { try { ApplicationContext context = new ClassPathXmlApplicationContext( "Spring3AndHibernate-servlet.xml"); IUserBusinessObject userBusinessObject = (IUserBusinessObject) context .getBean("userBusiness"); User user = (User) context.getBean("user1"); user.setPassword("pass"); user.setUsername("tsegay"); System.out.println(user.getPassword()); userBusinessObject.delete(user); User user2 = new User(); user2.setUsername("habest"); user2.setPassword("pass1"); System.out.println(user2.getPassword()); /* * userBusinessObject.save(user2); * * User user3 = userBusinessObject.searchUserbyId("tsegay"); * System.out.println("Search Result: " + user3.getUsername()); */ System.out.println("Success"); } catch (Exception e) { e.printStackTrace(); } } } my application context is: <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd"> <!-- data source --> <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="com.mysql.jdbc.Driver" /> <property name="url" value="jdbc:mysql://localhost:3306/test" /> <property name="username" value="test" /> <property name="password" value="password" /> </bean> <!-- session factory --> <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"> <property name="dataSource"> <ref bean="dataSource" /> </property> <property name="hibernateProperties"> <props> <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop> <prop key="hibernate.show_sql">true</prop> </props> </property> </bean> <!-- exposed person business object --> <bean id="userBusiness" class="edu.acct.tsegay.business.UserBusinessObject"> <property name="userDao" ref="userDao" /> </bean> <bean id="user1" class="edu.acct.tsegay.model.User"> <property name="username" value="tse" /> <property name="password" value="pass" /> </bean> <!-- Data Access Object --> <bean id="userDao" class="edu.acct.tsegay.dao.UserDao"> <property name="sessionFactory" ref="sessionFactory" /> </bean> </beans> My User Model is: package edu.acct.tsegay.model; import java.io.Serializable; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.Version; import org.hibernate.annotations.NaturalId; @Entity public class User implements Serializable { /** * */ private static final long serialVersionUID = 1L; private String username; private String password; private Integer VERSION; @Version public Integer getVERSION() { return VERSION; } public void setVERSION(Integer vERSION) { VERSION = vERSION; } @NaturalId public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } } My DAO is: package edu.acct.tsegay.dao; import edu.acct.tsegay.model.User; import org.hibernate.SessionFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.orm.hibernate3.HibernateTemplate; import org.springframework.stereotype.Repository; @Repository public class UserDao implements IUserDao { private SessionFactory sessionFactory; private HibernateTemplate hibernateTemplate; public SessionFactory getSessionFactory() { return sessionFactory; } @Autowired public void setSessionFactory(SessionFactory sessionFactory) { this.sessionFactory = sessionFactory; this.hibernateTemplate = new HibernateTemplate(sessionFactory); } public void save(User user) { // TODO Auto-generated method stub // getHibernateTemplate().save(user); this.hibernateTemplate.save(user); } public void delete(User user) { // TODO Auto-generated method stub this.hibernateTemplate.delete(user); } public User searchUserbyId(String username) { // TODO Auto-generated method stub return this.hibernateTemplate.get(User.class, username); } } And this my stacktrace error when i run the program: pass org.springframework.orm.hibernate3.HibernateSystemException: Unknown entity: edu.acct.tsegay.model.User; nested exception is org.hibernate.MappingException: Unknown entity: edu.acct.tsegay.model.User at org.springframework.orm.hibernate3.SessionFactoryUtils.convertHibernateAccessException(SessionFactoryUtils.java:679) at org.springframework.orm.hibernate3.HibernateAccessor.convertHibernateAccessException(HibernateAccessor.java:412) at org.springframework.orm.hibernate3.HibernateTemplate.doExecute(HibernateTemplate.java:411) at org.springframework.orm.hibernate3.HibernateTemplate.executeWithNativeSession(HibernateTemplate.java:374) at org.springframework.orm.hibernate3.HibernateTemplate.delete(HibernateTemplate.java:837) at org.springframework.orm.hibernate3.HibernateTemplate.delete(HibernateTemplate.java:833) at edu.acct.tsegay.dao.UserDao.delete(UserDao.java:34) at edu.acct.tsegay.business.UserBusinessObject.delete(UserBusinessObject.java:30) at edu.acct.tsegay.common.App.main(App.java:23) Caused by: org.hibernate.MappingException: Unknown entity: edu.acct.tsegay.model.User at org.hibernate.impl.SessionFactoryImpl.getEntityPersister(SessionFactoryImpl.java:580) at org.hibernate.impl.SessionImpl.getEntityPersister(SessionImpl.java:1365) at org.hibernate.event.def.DefaultDeleteEventListener.onDelete(DefaultDeleteEventListener.java:100) at org.hibernate.event.def.DefaultDeleteEventListener.onDelete(DefaultDeleteEventListener.java:74) at org.hibernate.impl.SessionImpl.fireDelete(SessionImpl.java:793) at org.hibernate.impl.SessionImpl.delete(SessionImpl.java:771) at org.springframework.orm.hibernate3.HibernateTemplate$25.doInHibernate(HibernateTemplate.java:843) at org.springframework.orm.hibernate3.HibernateTemplate.doExecute(HibernateTemplate.java:406) ... 6 more Please let me know if you need any more of my configuration. Any help is much appreciated..

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• png image store in database and retrieve in android 1.5

  - by hany

  hai, I am new to android. I have problem. This is my code but it will not work, the problem is in view binder. Please correct it. // this is my activity package com.android.Fruits2; import java.util.ArrayList; import java.util.HashMap; import android.app.ListActivity; import android.database.Cursor; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.os.Bundle; import android.widget.SimpleAdapter; import android.widget.SimpleCursorAdapter; import android.widget.SimpleAdapter.ViewBinder; public class Fruits2 extends ListActivity { private DBhelper mDB; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // setContentView(R.layout.main); mDB = new DBhelper(this); mDB.Reset(); Bitmap img = BitmapFactory.decodeResource(getResources(), R.drawable.icon); mDB.createPersonEntry(new PersonData(img, "Harsha", 24,"mca")); String[] columns = {mDB.KEY_ID, mDB.KEY_IMG, mDB.KEY_NAME, mDB.KEY_AGE, mDB.KEY_STUDY}; String table = mDB.PERSON_TABLE; Cursor c = mDB.getHandle().query(table, columns, null, null, null, null, null); startManagingCursor(c); SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.data, c, new String[] {mDB.KEY_IMG, mDB.KEY_NAME, mDB.KEY_AGE, mDB.KEY_STUDY}, new int[] {R.id.img, R.id.name, R.id.age,R.id.study}); adapter.setViewBinder( new MyViewBinder()); setListAdapter(adapter); } } //my viewbinder package com.android.Fruits2; import android.database.Cursor; import android.graphics.BitmapFactory; import android.view.View; import android.widget.ImageView; import android.widget.SimpleCursorAdapter; public class MyViewBinder implements SimpleCursorAdapter.ViewBinder { public boolean setViewValue(View view, Cursor cursor, int columnIndex) { if( (view instanceof ImageView) ) { ImageView iv = (ImageView) view; byte[] img = cursor.getBlob(columnIndex); iv.setImageBitmap(BitmapFactory.decodeByteArray(img, 0, img.length)); return true; } return false; } } // data package com.android.Fruits2; import android.graphics.Bitmap; public class PersonData { private Bitmap bmp; private String name; private int age; private String study; public PersonData(Bitmap b, String n, int k, String v) { bmp = b; name = n; age = k; study = v; } public Bitmap getBitmap() { return bmp; } public String getName() { return name; } public int getAge() { return age; } public String getStudy() { return study; } } //dbhelper package com.android.Fruits2; import java.io.ByteArrayOutputStream; import android.content.ContentValues; import android.content.Context; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenHelper; import android.graphics.Bitmap; import android.provider.BaseColumns; public class DBhelper { public static final String KEY_ID = BaseColumns._ID; public static final String KEY_NAME = "name"; public static final String KEY_AGE = "age"; public static final String KEY_STUDY = "study"; public static final String KEY_IMG = "image"; private DatabaseHelper mDbHelper; private SQLiteDatabase mDb; private static final String DATABASE_NAME = "PersonalDB"; private static final int DATABASE_VERSION = 1; public static final String PERSON_TABLE = "Person"; private static final String CREATE_PERSON_TABLE = "create table "+PERSON_TABLE+" (" +KEY_ID+" integer primary key autoincrement, " +KEY_IMG+" blob not null, " +KEY_NAME+" text not null , " +KEY_AGE+" integer not null, " +KEY_STUDY+" text not null);"; private final Context mCtx; private boolean opened = false; private static class DatabaseHelper extends SQLiteOpenHelper { DatabaseHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } public void onCreate(SQLiteDatabase db) { db.execSQL(CREATE_PERSON_TABLE); } public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { db.execSQL("DROP TABLE IF EXISTS "+PERSON_TABLE); onCreate(db); } } public void Reset() { openDB(); mDbHelper.onUpgrade(this.mDb, 1, 1); closeDB(); } public DBhelper(Context ctx) { mCtx = ctx; mDbHelper = new DatabaseHelper(mCtx); } private SQLiteDatabase openDB() { if(!opened) mDb = mDbHelper.getWritableDatabase(); opened = true; return mDb; } public SQLiteDatabase getHandle() { return openDB(); } private void closeDB() { if(opened) mDbHelper.close(); opened = false; } public void createPersonEntry(PersonData about) { openDB(); ByteArrayOutputStream out = new ByteArrayOutputStream(); about.getBitmap().compress(Bitmap.CompressFormat.PNG, 100, out); ContentValues cv = new ContentValues(); cv.put(KEY_IMG, out.toByteArray()); cv.put(KEY_NAME, about.getName()); cv.put(KEY_AGE, about.getAge()); cv.put(KEY_STUDY, about.getStudy()); mDb.insert(PERSON_TABLE, null, cv); closeDB(); } } //data.xml <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="wrap_content"> <ImageView android:id = "@+id/img" android:layout_width = "wrap_content" android:layout_height = "wrap_content" > </ImageView> <TextView android:id = "@+id/name" android:layout_width = "wrap_content" android:layout_height = "wrap_content" android:textSize="15dp" android:textColor="#ff0000" > </TextView> <TextView android:id = "@+id/age" android:layout_width = "wrap_content" android:layout_height = "wrap_content" android:textSize="15dp" android:textColor="#ff0000" /> <TextView android:id = "@+id/study" android:layout_width = "wrap_content" android:layout_height = "wrap_content" android:textSize="15dp" android:textColor="#ff0000" /> </LinearLayout> When I run this in android 1.6 and 2.1, it works. But when I run in android 1.5, not work. My application is android 1.5. Please correct and send code to me. Thank you.

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• Type '_Default' already contains a definition

  - by salvationishere

  I am developing a C# VS 2008 / SQL Server 2008 website. I have a Gridview. I included the Default.aspx and aspx.cs files below. But when I build this I get the below error: The Type '_Default' already contains a definition for 'btnOWrite' What do I need to do to fix this? I am not getting any errors now; just that this grid does not show up. Thanks! ASPX file: <%@ Page Language="C#" MasterPageFile="~/Site.master" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" Title="Untitled Page" %> <asp:Content ID="Content1" ContentPlaceHolderID="MainContent" runat="Server"> <asp:Panel runat="server" ID="AuthenticatedMessagePanel"> <asp:Label runat="server" ID="WelcomeBackMessage"></asp:Label> <table> <tr> <td> <asp:Label ID="tableLabel" runat="server" Font-Bold="True" Text="Select target table:"></asp:Label> </td> <td> <asp:Label ID="inputLabel" runat="server" Font-Bold="True" Text="Select input file:"></asp:Label> </td> </tr> <tr> <td valign="top"> <asp:Label ID="feedbackLabel" runat="server"></asp:Label> <asp:SqlDataSource ID="SelectTables" runat="server" ConnectionString="<%$ ConnectionStrings:AdventureWorks3_SelectTables %>" SelectCommand="getTableNames" SelectCommandType="StoredProcedure"> <SelectParameters> <asp:QueryStringParameter DefaultValue="Person" Name="SchemaName" QueryStringField="SchemaName" Type="String" /> </SelectParameters> </asp:SqlDataSource> <asp:GridView ID="GridView1" DataSourceID="SelectTables" runat="server" Style="width: 400px;" CellPadding="4" ForeColor="#333333" GridLines="None" OnSelectedIndexChanged="GridView1_SelectedIndexChanged" AutoGenerateSelectButton="True" DataKeyNames="TABLE_NAME"> <RowStyle BackColor="#F7F6F3" ForeColor="#333333" /> <Columns> <asp:BoundField HeaderText="TABLE_NAME" DataField="TABLE_NAME" /> </Columns> <FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /> <PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" /> <SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" /> <HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /> <EditRowStyle BackColor="#999999" /> <AlternatingRowStyle BackColor="White" ForeColor="#284775" /> </asp:GridView> </td> <td valign="top"> <input id="uploadFile" type="file" size="26" runat="server" name="uploadFile" title="UploadFile" class="greybar" enableviewstate="True" /> </td> </tr> </table> <table> <tr> <td style="width:150px; height:50px"></td> <td valign="bottom" style="width:150px; height:50px"> <input id="btnOWrite" type="submit" value="Overwrite Data" runat="server" class="greybar" onserverclick="btnOWrite_Click" name="btnOWrite" />&nbsp; </td> <td style="width:100px"></td> <td valign="bottom" style="width:150px; height:50px"> <input id="btnAppend" type="submit" value="Append Data" runat="server" class="greybar" onserverclick="btnAppend_Click" name="btnAppend" /> </td> </tr> </table> </asp:Panel> <asp:Panel runat="Server" ID="AnonymousMessagePanel"> <asp:HyperLink runat="server" ID="lnkLogin" Text="Log In" NavigateUrl="~/Login.aspx"> </asp:HyperLink> </asp:Panel> </asp:Content> ASPX.CS file: using System; using System.Collections; using System.Configuration; using System.Data; using System.Linq; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.HtmlControls; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Xml.Linq; using System.Collections.Generic; using System.IO; using System.Drawing; using System.ComponentModel; using System.Data.SqlClient; using ADONET_namespace; using System.Security.Principal; //using System.Windows; public partial class _Default : System.Web.UI.Page //namespace AddFileToSQL { //protected System.Web.UI.HtmlControls.HtmlInputFile uploadFile; protected System.Web.UI.HtmlControls.HtmlInputButton btnOWrite; protected System.Web.UI.HtmlControls.HtmlInputButton btnAppend; protected System.Web.UI.WebControls.Label Label1; protected static string inputfile = ""; public static string targettable; public static string selection; // Number of controls added to view state protected int default_NumberOfControls { get { if (ViewState["default_NumberOfControls"] != null) { return (int)ViewState["default_NumberOfControls"]; } else { return 0; } } set { ViewState["default_NumberOfControls"] = value; } } protected void uploadFile_onclick(object sender, EventArgs e) { } protected void Load_GridData() { //GridView1.DataSource = ADONET_methods.DisplaySchemaTables(); //GridView1.DataBind(); } protected void btnOWrite_Click(object sender, EventArgs e) { if (uploadFile.PostedFile.ContentLength > 0) { feedbackLabel.Text = "You do not have sufficient access to overwrite table records."; } else { feedbackLabel.Text = "This file does not contain any data."; } } protected void btnAppend_Click(object sender, EventArgs e) { string fullpath = Page.Request.PhysicalApplicationPath; string path = uploadFile.PostedFile.FileName; if (File.Exists(path)) { // Create a file to write to. try { StreamReader sr = new StreamReader(path); string s = ""; while (sr.Peek() > 0) s = sr.ReadLine(); sr.Close(); } catch (IOException exc) { Console.WriteLine(exc.Message + "Cannot open file."); return; } } if (uploadFile.PostedFile.ContentLength > 0) { inputfile = System.IO.File.ReadAllText(path); Session["Message"] = inputfile; Response.Redirect("DataMatch.aspx"); } else { feedbackLabel.Text = "This file does not contain any data."; } } protected void Page_Load(object sender, EventArgs e) { if (Request.IsAuthenticated) { WelcomeBackMessage.Text = "Welcome back, " + User.Identity.Name + "!"; // Reference the CustomPrincipal / CustomIdentity CustomIdentity ident = User.Identity as CustomIdentity; if (ident != null) WelcomeBackMessage.Text += string.Format(" You are the {0} of {1}.", ident.Title, ident.CompanyName); AuthenticatedMessagePanel.Visible = true; AnonymousMessagePanel.Visible = false; if (!Page.IsPostBack) { Load_GridData(); } } else { AuthenticatedMessagePanel.Visible = false; AnonymousMessagePanel.Visible = true; } } protected void GridView1_SelectedIndexChanged(object sender, EventArgs e) { GridViewRow row = GridView1.SelectedRow; targettable = row.Cells[2].Text; } }

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• Can this Query be corrected or different table structure needed? (database dumps provided)

  - by sandeepan

  This is a bit lengthy but I have provided sufficient details and kept things very clear. Please see if you can help. (I will surely accept answer if it solves my problem) I am sure a person experienced with this can surely help or suggest me to decide the tables structure. About the system:- There are tutors who create classes A tags based search approach is being followed Tag relations are created/edited when new tutors registers/edits profile data and when tutors create classes (this makes tutors and classes searcheable).For simplicity, let us consider only tutor name and class name are the fields which are matched against search keywords. In this example, I am considering - tutor "Sandeepan Nath" has created a class called "first class" tutor "Bob Cratchit" has created a class called "new class" Desired search results- AND logic to be appied on the search keywords and match against class and tutor data(class name + tutor name), in other words, All those classes be shown such that all the search terms are present in the class name or its tutor name. Example to be clear - Searching "first class" returns class with id_wc = 1. Working Searching "Sandeepan class" should also return class with id_wc = 1. Not working in System 2. Problem with profile editing and searching To tell in one sentence, I am facing a conflict between the ease of profile edition (edition of tag relations when tutor profiles are edited) and the ease of search logic. In the beginning, we had one table structure and search was easy but tag edition logic was very clumsy and unmaintainable(Check System 1 in the section below) . So we created separate tag relations tables to make profile edition simpler but search has become difficult. Please dump the tables so that you can run the search query I have given below and see the results. System 1 (previous system - search easy - profile edition difficult):- Only one table called All_Tag_Relations table had the all the tag relations. The tags table below is common to both systems 1 and 2. CREATE TABLE IF NOT EXISTS `all_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) unsigned DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `all_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`, `id_wc`) VALUES (1, 1, 1, NULL), (2, 2, 1, NULL), (3, 1, 1, 1), (4, 2, 1, 1), (5, 3, 1, 1), (6, 4, 1, 1), (7, 6, 2, NULL), (8, 7, 2, NULL), (9, 6, 2, 2), (10, 7, 2, 2), (11, 5, 2, 2), (12, 4, 2, 2); CREATE TABLE IF NOT EXISTS `tags` ( `id_tag` int(10) unsigned NOT NULL AUTO_INCREMENT, `tag` varchar(255) DEFAULT NULL, PRIMARY KEY (`id_tag`), UNIQUE KEY `tag` (`tag`), KEY `id_tag` (`id_tag`), KEY `tag_2` (`tag`), KEY `tag_3` (`tag`), KEY `tag_4` (`tag`), FULLTEXT KEY `tag_5` (`tag`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; INSERT INTO `tags` (`id_tag`, `tag`) VALUES (1, 'Sandeepan'), (2, 'Nath'), (3, 'first'), (4, 'class'), (5, 'new'), (6, 'Bob'), (7, 'Cratchit'); Please note that for every class, the tag rels of its tutor have to be duplicated. Example, for class with id_wc=1, the tag rel records with id_tag_rel = 3 and 4 are actually extras if you compare with the tag rel records with id_tag_rel = 1 and 2. System 2 (present system - profile edition easy, search difficult) Two separate tables Tutors_Tag_Relations and Webclasses_Tag_Relations have the corresponding tag relations data (Please dump into a separate database)- CREATE TABLE IF NOT EXISTS `tutors_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `tutors_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`) VALUES (1, 1, 1), (2, 2, 1), (3, 6, 2), (4, 7, 2); CREATE TABLE IF NOT EXISTS `webclasses_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `webclasses_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `webclasses_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`, `id_wc`) VALUES (1, 3, 1, 1), (2, 4, 1, 1), (3, 5, 2, 2), (4, 4, 2, 2); CREATE TABLE IF NOT EXISTS `tags` ( `id_tag` int(10) unsigned NOT NULL AUTO_INCREMENT, `tag` varchar(255) DEFAULT NULL, PRIMARY KEY (`id_tag`), UNIQUE KEY `tag` (`tag`), KEY `id_tag` (`id_tag`), KEY `tag_2` (`tag`), KEY `tag_3` (`tag`), KEY `tag_4` (`tag`), FULLTEXT KEY `tag_5` (`tag`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; INSERT INTO `tags` (`id_tag`, `tag`) VALUES (1, 'Sandeepan'), (2, 'Nath'), (3, 'first'), (4, 'class'), (5, 'new'), (6, 'Bob'), (7, 'Cratchit'); CREATE TABLE IF NOT EXISTS `all_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) unsigned DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; insert into All_Tag_Relations select NULL,id_tag,id_tutor,NULL from Tutors_Tag_Relations; insert into All_Tag_Relations select NULL,id_tag,id_tutor,id_wc from Webclasses_Tag_Relations; Here you can see how easily tutor first name can be edited only in one place. But search has become really difficult, so on being advised to use a Temporary table, I am creating one at every search request, then dumping all the necessary data and then searching from it, I am creating this All_Tag_Relations table at search run time. Here I am just dumping all the data from the two tables Tutors_Tag_Relations and Webclasses_Tag_Relations. But, I am still not able to get classes if I search with tutor name This is the query which searches "first class". Running them on both the systems shows correct results (returns the class with id_wc = 1). SELECT wtagrels.id_wc,SUM(DISTINCT( wtagrels.id_tag =3)) AS key_1_total_matches, SUM(DISTINCT( wtagrels.id_tag =4)) AS key_2_total_matches FROM all_tag_relations AS wtagrels WHERE ( wtagrels.id_tag =3 OR wtagrels.id_tag =4 ) GROUP BY wtagrels.id_wc HAVING key_1_total_matches = 1 AND key_2_total_matches = 1 LIMIT 0, 20 But, searching for "Sandeepan class" works only with the 1st system Here is the query which searches "Sandeepan class" SELECT wtagrels.id_wc,SUM(DISTINCT( wtagrels.id_tag =1)) AS key_1_total_matches, SUM(DISTINCT( wtagrels.id_tag =4)) AS key_2_total_matches FROM all_tag_relations AS wtagrels WHERE ( wtagrels.id_tag =1 OR wtagrels.id_tag =4 ) GROUP BY wtagrels.id_wc HAVING key_1_total_matches = 1 AND key_2_total_matches = 1 LIMIT 0, 20 Can anybody alter this query and somehow do a proper join or something to get correct results. That solves my problem in a nice way. As you can figure out, the reason why it does not work in system 2 is that in system 1, for every class, one additional tag relation linking class and tutor name is present. e.g. for class first class, (records with id_tag_rel 3 and 4) which returns the class on searching with tutor name. So, you see the trade-off between the search and profile edition difficulty with the two systems. How do I overcome both. I have to reach a conclusion soon. So far my reasoning is it is definitely not good from a code maintainability point of view to follow the single tag rel table structure of system one, because in a real system while editing a field like "tutor qualifications", there can be as many records in tag rels table as there are words in qualification of a tutor (one word in a field = one tag relation). Now suppose a tutor has 100 classes. When he edits his qualification, all the tag rel rows corresponding to him are deleted and then as many copies are to be created (as per the new qualification data) as there are classes. This becomes particularly difficult if later more searcheable fields are added. The code cannot be robust. Is the best solution to follow system 2 (edition has to be in one table - no extra work for each and every class) and somehow re-create the all_tag_relations table like system 1 (from the tables tutor_tag_relations and webclasses_tag_relations), creating the extra tutor tag rels for each and every class by a tutor (which is currently missing in system 2's temporary all_tag_relations table). That would be a time consuming logic script. I doubt that table can be recreated without resorting to PHP sript (mysql alone cannot do that). But the problem is that running all this at search time will make search definitely slow. So, how do such systems work? How are such situations handled? I thought about we can run a cron which initiates that PHP script, say every 1 minute and replaces the existing all_tag_relations table as per new tag rels from tutor_tag_relations and webclasses_tag_relations (replaces means creates a new table, deletes the original and renames the new one as all_tag_relations, otherwise search won't work during that period- or is there any better way to that?). Anyway, the result would be that any changes by tutors will reflect in search in the next 1 minute and not immediately. An alternateve would be to initate that PHP script every time a tutor edits his profile. But here again, since many users may edit their profiles concurrently, will the creation of so many tables be a burden and can mysql make the server slow? Any help would be appreciated and working solution will be accepted as answer. Thanks, Sandeepan

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• Authoritative sources about Database vs. Flatfile decision

  - by FastAl

  <tldr>looking for a reference to a book or other undeniably authoritative source that gives reasons when you should choose a database vs. when you should choose other storage methods. I have provided an un-authoritative list of reasons about 2/3 of the way down this post.</tldr> I have a situation at my company where a database is being used where it would be better to use another solution (in this case, an auto-generated piece of source code that contains a static lookup table, searched by binary sort). Normally, a database would be an OK solution even though the problem does not require a database, e.g, none of the elements of ACID are needed, as it is read-only data, updated about every 3-5 years (also requiring other sourcecode changes), and fits in memory, and can be keyed into via binary search (a tad faster than db, but speed is not an issue). The problem is that this code runs on our enterprise server, but is shared with several PC platforms (some disconnected, some use a central DB, etc.), and parts of it are managed by multiple programming units, parts by the DBAs, parts even by mathematicians in another department, etc. These hit their own platform’s version of their databases (containing their own copy of the static data). What happens is that every implementation, every little change, something different goes wrong. There are many other issues as well. I can’t even use a flatfile, because one mode of running on our enterprise server does not have permission to read files (only databases, and of course, its own literal storage, e.g., in-source table). Of course, other parts of the system use databases in proper, less obscure manners; there is no problem with those parts. So why don’t we just change it? I don’t have administrative ability to force a change. But I’m affected because sometimes I have to help fix the problems, but mostly because it causes outages and tons of extra IT time by other programmers and d*mmit that makes me mad! The reason neither management, nor the designers of the system, can see the problem is that they propose a solution that won’t work: increase communication; implement more safeguards and standards; etc. But every time, in a different part of the already-pared-down but still multi-step processes, a few different diligent, hard-working, top performing IT personnel make a unique subtle error that causes it to fail, sometimes after the last round of testing! And in general these are not single-person failures, but understandable miscommunications. And communication at our company is actually better than most. People just don't think that's the case because they haven't dug into the matter. However, I have it on very good word from somebody with extensive formal study of sociology and psychology that the relatively small amount of less-than-proper database usage in this gigantic cross-platform multi-source, multi-language project is bureaucratically un-maintainable. Impossible. No chance. At least with Human Beings in the loop, and it can’t be automated. In addition, the management and developers who could change this, though intelligent and capable, don’t understand the rigidity of this ‘how humans are’ issue, and are not convincible on the matter. The reason putting the static data in sourcecode will solve the problem is, although the solution is less sexy than a database, it would function with no technical drawbacks; and since the sharing of sourcecode already works very well, you basically erase any database-related effort from this section of the project, along with all the drawbacks of it that are causing problems. OK, that’s the background, for the curious. I won’t be able to convince management that this is an unfixable sociological problem, and that the real solution is coding around these limits of human nature, just as you would code around a bug in a 3rd party component that you can’t change. So what I have to do is exploit the unsuitableness of the database solution, and not do it using logic, but rather authority. I am aware of many reasons, and posts on this site giving reasons for one over the other; I’m not looking for lists of reasons like these (although you can add a comment if I've miss a doozy): WHY USE A DATABASE? instead of flatfile/other DB vs. file: if you need... Random Read / Transparent search optimization Advanced / varied / customizable Searching and sorting capabilities Transaction/rollback Locks, semaphores Concurrency control / Shared users Security 1-many/m-m is easier Easy modification Scalability Load Balancing Random updates / inserts / deletes Advanced query Administrative control of design, etc. SQL / learning curve Debugging / Logging Centralized / Live Backup capabilities Cached queries / dvlp & cache execution plans Interleaved update/read Referential integrity, avoid redundant/missing/corrupt/out-of-sync data Reporting (from on olap or oltp db) / turnkey generation tools [Disadvantages:] Important to get right the first time - professional design - but only b/c it's meant to last s/w & h/w cost Usu. over a network, speed issue (best vs. best design vs. local=even then a separate process req's marshalling/netwk layers/inter-p comm) indicies and query processing can stand in the way of simple processing (vs. flatfile) WHY USE FLATFILE: If you only need... Sequential Row processing only Limited usage append only (no reading, no master key/update) Only Update the record you're reading (fixed length recs only) Too big to fit into memory If Local disk / read-ahead network connection Portability / small system Email / cut & Paste / store as document by novice - simple format Low design learning curve but high cost later WHY USE IN-MEMORY/TABLE (tables, arrays, etc.): if you need... Processing a single db/ff record that was imported Known size of data Static data if hardcoding the table Narrow, unchanging use (e.g., one program or proc) -includes a class that will be shared, but encapsulates its data manipulation Extreme speed needed / high transaction frequency Random access - but search is dependent on implementation Following are some other posts about the topic: http://stackoverflow.com/questions/1499239/database-vs-flat-text-file-what-are-some-technical-reasons-for-choosing-one-over http://stackoverflow.com/questions/332825/are-flat-file-databases-any-good http://stackoverflow.com/questions/2356851/database-vs-flat-files http://stackoverflow.com/questions/514455/databases-vs-plain-text/514530 What I’d like to know is if anybody could recommend a hard, authoritative source containing these reasons. I’m looking for a paper book I can buy, or a reputable website with whitepapers about the issue (e.g., Microsoft, IBM), not counting the user-generated content on those sites. This will have a greater change to elicit a change that I’m looking for: less wasted programmer time, and more reliable programs. Thanks very much for your help. You win a prize for reading such a large post!

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• Can this Query can be corrected or different table structure needed? (question is clear, detailed, d

  - by sandeepan

  This is a bit lengthy but I have provided sufficient details and kept things very clear. Please see if you can help. (I will surely accept answer if it solves my problem) I am sure a person experienced with this can surely help or suggest me to decide the tables structure. About the system:- There are tutors who create classes A tags based search approach is being followed Tag relations are created/edited when new tutors registers/edits profile data and when tutors create classes (this makes tutors and classes searcheable).For simplicity, let us consider only tutor name and class name are the fields which are matched against search keywords. In this example, I am considering - tutor "Sandeepan Nath" has created a class called "first class" tutor "Bob Cratchit" has created a class called "new class" Desired search results- AND logic to be appied on the search keywords and match against class and tutor data(class name + tutor name), in other words, All those classes be shown such that all the search terms are present in the class name or its tutor name. Example to be clear - Searching "first class" returns class with id_wc = 1. Working Searching "Sandeepan class" should also return class with id_wc = 1. Not working in System 2. Problem with profile editing and searching To tell in one sentence, I am facing a conflict between the ease of profile edition (edition of tag relations when tutor profiles are edited) and the ease of search logic. In the beginning, we had one table structure and search was easy but tag edition logic was very clumsy and unmaintainable(Check System 1 in the section below) . So we created separate tag relations tables to make profile edition simpler but search has become difficult. Please dump the tables so that you can run the search query I have given below and see the results. System 1 (previous system - search easy - profile edition difficult):- Only one table called All_Tag_Relations table had the all the tag relations. The tags table below is common to both systems 1 and 2. CREATE TABLE IF NOT EXISTS `all_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) unsigned DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `all_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`, `id_wc`) VALUES (1, 1, 1, NULL), (2, 2, 1, NULL), (3, 1, 1, 1), (4, 2, 1, 1), (5, 3, 1, 1), (6, 4, 1, 1), (7, 6, 2, NULL), (8, 7, 2, NULL), (9, 6, 2, 2), (10, 7, 2, 2), (11, 5, 2, 2), (12, 4, 2, 2); CREATE TABLE IF NOT EXISTS `tags` ( `id_tag` int(10) unsigned NOT NULL AUTO_INCREMENT, `tag` varchar(255) DEFAULT NULL, PRIMARY KEY (`id_tag`), UNIQUE KEY `tag` (`tag`), KEY `id_tag` (`id_tag`), KEY `tag_2` (`tag`), KEY `tag_3` (`tag`), KEY `tag_4` (`tag`), FULLTEXT KEY `tag_5` (`tag`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; INSERT INTO `tags` (`id_tag`, `tag`) VALUES (1, 'Sandeepan'), (2, 'Nath'), (3, 'first'), (4, 'class'), (5, 'new'), (6, 'Bob'), (7, 'Cratchit'); Please note that for every class, the tag rels of its tutor have to be duplicated. Example, for class with id_wc=1, the tag rel records with id_tag_rel = 3 and 4 are actually extras if you compare with the tag rel records with id_tag_rel = 1 and 2. System 2 (present system - profile edition easy, search difficult) Two separate tables Tutors_Tag_Relations and Webclasses_Tag_Relations have the corresponding tag relations data (Please dump into a separate database)- CREATE TABLE IF NOT EXISTS `tutors_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `tutors_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`) VALUES (1, 1, 1), (2, 2, 1), (3, 6, 2), (4, 7, 2); CREATE TABLE IF NOT EXISTS `webclasses_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `webclasses_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `webclasses_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`, `id_wc`) VALUES (1, 3, 1, 1), (2, 4, 1, 1), (3, 5, 2, 2), (4, 4, 2, 2); CREATE TABLE IF NOT EXISTS `tags` ( `id_tag` int(10) unsigned NOT NULL AUTO_INCREMENT, `tag` varchar(255) DEFAULT NULL, PRIMARY KEY (`id_tag`), UNIQUE KEY `tag` (`tag`), KEY `id_tag` (`id_tag`), KEY `tag_2` (`tag`), KEY `tag_3` (`tag`), KEY `tag_4` (`tag`), FULLTEXT KEY `tag_5` (`tag`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; INSERT INTO `tags` (`id_tag`, `tag`) VALUES (1, 'Sandeepan'), (2, 'Nath'), (3, 'first'), (4, 'class'), (5, 'new'), (6, 'Bob'), (7, 'Cratchit'); CREATE TABLE IF NOT EXISTS `all_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) unsigned DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; insert into All_Tag_Relations select NULL,id_tag,id_tutor,NULL from Tutors_Tag_Relations; insert into All_Tag_Relations select NULL,id_tag,id_tutor,id_wc from Webclasses_Tag_Relations; Here you can see how easily tutor first name can be edited only in one place. But search has become really difficult, so on being advised to use a Temporary table, I am creating one at every search request, then dumping all the necessary data and then searching from it, I am creating this All_Tag_Relations table at search run time. Here I am just dumping all the data from the two tables Tutors_Tag_Relations and Webclasses_Tag_Relations. But, I am still not able to get classes if I search with tutor name This is the query which searches "first class". Running them on both the systems shows correct results (returns the class with id_wc = 1). SELECT wtagrels.id_wc,SUM(DISTINCT( wtagrels.id_tag =3)) AS key_1_total_matches, SUM(DISTINCT( wtagrels.id_tag =4)) AS key_2_total_matches FROM all_tag_relations AS wtagrels WHERE ( wtagrels.id_tag =3 OR wtagrels.id_tag =4 ) GROUP BY wtagrels.id_wc HAVING key_1_total_matches = 1 AND key_2_total_matches = 1 LIMIT 0, 20 But, searching for "Sandeepan class" works only with the 1st system Here is the query which searches "Sandeepan class" SELECT wtagrels.id_wc,SUM(DISTINCT( wtagrels.id_tag =1)) AS key_1_total_matches, SUM(DISTINCT( wtagrels.id_tag =4)) AS key_2_total_matches FROM all_tag_relations AS wtagrels WHERE ( wtagrels.id_tag =1 OR wtagrels.id_tag =4 ) GROUP BY wtagrels.id_wc HAVING key_1_total_matches = 1 AND key_2_total_matches = 1 LIMIT 0, 20 Can anybody alter this query and somehow do a proper join or something to get correct results. That solves my problem in a nice way. As you can figure out, the reason why it does not work in system 2 is that in system 1, for every class, one additional tag relation linking class and tutor name is present. e.g. for class first class, (records with id_tag_rel 3 and 4) which returns the class on searching with tutor name. So, you see the trade-off between the search and profile edition difficulty with the two systems. How do I overcome both. I have to reach a conclusion soon. So far my reasoning is it is definitely not good from a code maintainability point of view to follow the single tag rel table structure of system one, because in a real system while editing a field like "tutor qualifications", there can be as many records in tag rels table as there are words in qualification of a tutor (one word in a field = one tag relation). Now suppose a tutor has 100 classes. When he edits his qualification, all the tag rel rows corresponding to him are deleted and then as many copies are to be created (as per the new qualification data) as there are classes. This becomes particularly difficult if later more searcheable fields are added. The code cannot be robust. Is the best solution to follow system 2 (edition has to be in one table - no extra work for each and every class) and somehow re-create the all_tag_relations table like system 1 (from the tables tutor_tag_relations and webclasses_tag_relations), creating the extra tutor tag rels for each and every class by a tutor (which is currently missing in system 2's temporary all_tag_relations table). That would be a time consuming logic script. I doubt that table can be recreated without resorting to PHP sript (mysql alone cannot do that). But the problem is that running all this at search time will make search definitely slow. So, how do such systems work? How are such situations handled? I thought about we can run a cron which initiates that PHP script, say every 1 minute and replaces the existing all_tag_relations table as per new tag rels from tutor_tag_relations and webclasses_tag_relations (replaces means creates a new table, deletes the original and renames the new one as all_tag_relations, otherwise search won't work during that period- or is there any better way to that?). Anyway, the result would be that any changes by tutors will reflect in search in the next 1 minute and not immediately. An alternateve would be to initate that PHP script every time a tutor edits his profile. But here again, since many users may edit their profiles concurrently, will the creation of so many tables be a burden and can mysql make the server slow? Any help would be appreciated and working solution will be accepted as answer. Thanks, Sandeepan

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• How do I prove I should put a table of values in source code instead of a database table?

  - by FastAl

  <tldr>looking for a reference to a book or other undeniably authoritative source that gives reasons when you should choose a database vs. when you should choose other storage methods. I have provided an un-authoritative list of reasons about 2/3 of the way down this post.</tldr> I have a situation at my company where a database is being used where it would be better to use another solution (in this case, an auto-generated piece of source code that contains a static lookup table, searched by binary sort). Normally, a database would be an OK solution even though the problem does not require a database, e.g, none of the elements of ACID are needed, as it is read-only data, updated about every 3-5 years (also requiring other sourcecode changes), and fits in memory, and can be keyed into via binary search (a tad faster than db, but speed is not an issue). The problem is that this code runs on our enterprise server, but is shared with several PC platforms (some disconnected, some use a central DB, etc.), and parts of it are managed by multiple programming units, parts by the DBAs, parts even by mathematicians in another department, etc. These hit their own platform’s version of their databases (containing their own copy of the static data). What happens is that every implementation, every little change, something different goes wrong. There are many other issues as well. I can’t even use a flatfile, because one mode of running on our enterprise server does not have permission to read files (only databases, and of course, its own literal storage, e.g., in-source table). Of course, other parts of the system use databases in proper, less obscure manners; there is no problem with those parts. So why don’t we just change it? I don’t have administrative ability to force a change. But I’m affected because sometimes I have to help fix the problems, but mostly because it causes outages and tons of extra IT time by other programmers and d*mmit that makes me mad! The reason neither management, nor the designers of the system, can see the problem is that they propose a solution that won’t work: increase communication; implement more safeguards and standards; etc. But every time, in a different part of the already-pared-down but still multi-step processes, a few different diligent, hard-working, top performing IT personnel make a unique subtle error that causes it to fail, sometimes after the last round of testing! And in general these are not single-person failures, but understandable miscommunications. And communication at our company is actually better than most. People just don't think that's the case because they haven't dug into the matter. However, I have it on very good word from somebody with extensive formal study of sociology and psychology that the relatively small amount of less-than-proper database usage in this gigantic cross-platform multi-source, multi-language project is bureaucratically un-maintainable. Impossible. No chance. At least with Human Beings in the loop, and it can’t be automated. In addition, the management and developers who could change this, though intelligent and capable, don’t understand the rigidity of this ‘how humans are’ issue, and are not convincible on the matter. The reason putting the static data in sourcecode will solve the problem is, although the solution is less sexy than a database, it would function with no technical drawbacks; and since the sharing of sourcecode already works very well, you basically erase any database-related effort from this section of the project, along with all the drawbacks of it that are causing problems. OK, that’s the background, for the curious. I won’t be able to convince management that this is an unfixable sociological problem, and that the real solution is coding around these limits of human nature, just as you would code around a bug in a 3rd party component that you can’t change. So what I have to do is exploit the unsuitableness of the database solution, and not do it using logic, but rather authority. I am aware of many reasons, and posts on this site giving reasons for one over the other; I’m not looking for lists of reasons like these (although you can add a comment if I've miss a doozy): WHY USE A DATABASE? instead of flatfile/other DB vs. file: if you need... Random Read / Transparent search optimization Advanced / varied / customizable Searching and sorting capabilities Transaction/rollback Locks, semaphores Concurrency control / Shared users Security 1-many/m-m is easier Easy modification Scalability Load Balancing Random updates / inserts / deletes Advanced query Administrative control of design, etc. SQL / learning curve Debugging / Logging Centralized / Live Backup capabilities Cached queries / dvlp & cache execution plans Interleaved update/read Referential integrity, avoid redundant/missing/corrupt/out-of-sync data Reporting (from on olap or oltp db) / turnkey generation tools [Disadvantages:] Important to get right the first time - professional design - but only b/c it's meant to last s/w & h/w cost Usu. over a network, speed issue (best vs. best design vs. local=even then a separate process req's marshalling/netwk layers/inter-p comm) indicies and query processing can stand in the way of simple processing (vs. flatfile) WHY USE FLATFILE: If you only need... Sequential Row processing only Limited usage append only (no reading, no master key/update) Only Update the record you're reading (fixed length recs only) Too big to fit into memory If Local disk / read-ahead network connection Portability / small system Email / cut & Paste / store as document by novice - simple format Low design learning curve but high cost later WHY USE IN-MEMORY/TABLE (tables, arrays, etc.): if you need... Processing a single db/ff record that was imported Known size of data Static data if hardcoding the table Narrow, unchanging use (e.g., one program or proc) -includes a class that will be shared, but encapsulates its data manipulation Extreme speed needed / high transaction frequency Random access - but search is dependent on implementation Following are some other posts about the topic: http://stackoverflow.com/questions/1499239/database-vs-flat-text-file-what-are-some-technical-reasons-for-choosing-one-over http://stackoverflow.com/questions/332825/are-flat-file-databases-any-good http://stackoverflow.com/questions/2356851/database-vs-flat-files http://stackoverflow.com/questions/514455/databases-vs-plain-text/514530 What I’d like to know is if anybody could recommend a hard, authoritative source containing these reasons. I’m looking for a paper book I can buy, or a reputable website with whitepapers about the issue (e.g., Microsoft, IBM), not counting the user-generated content on those sites. This will have a greater change to elicit a change that I’m looking for: less wasted programmer time, and more reliable programs. Thanks very much for your help. You win a prize for reading such a large post!

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• how to pass an id number string to this class

  - by Phil

  I'm very much a vb person, but have had to use this id number class in c#. I got it from http://www.codingsanity.com/idnumber.htm : using System; using System.Text.RegularExpressions; namespace Utilities.SouthAfrica { /// <summary> /// Represents a South African Identity Number. /// valid number = 7707215230080 /// invalid test number = 1234567891234 /// /// </summary> [Serializable()] public class IdentityNumber { #region Enumerations /// <summary> /// Indicates a gender. /// </summary> public enum PersonGender { Female = 0, Male = 5 } public enum PersonCitizenship { SouthAfrican = 0, Foreign = 1 } #endregion #region Declarations static Regex _expression; Match _match; const string _IDExpression = @"(?<Year>[0-9][0-9])(?<Month>([0][1-9])|([1][0-2]))(?<Day>([0-2][0-9])|([3][0-1]))(?<Gender>[0-9])(?<Series>[0-9]{3})(?<Citizenship>[0-9])(?<Uniform>[0-9])(?<Control>[0-9])"; #endregion #region Constuctors /// <summary> /// Sets up the shared objects for ID validation. /// </summary> static IdentityNumber() { _expression = new Regex(_IDExpression, RegexOptions.Compiled | RegexOptions.Singleline); } /// <summary> /// Creates the ID number from a string. /// </summary> /// <param name="IDNumber">The string ID number.</param> public IdentityNumber(string IDNumber) { _match = _expression.Match(IDNumber.Trim()); } #endregion #region Properties /// <summary> /// Indicates the date of birth encoded in the ID Number. /// </summary> /// <exception cref="System.ArgumentException">Thrown if the ID Number is not usable.</exception> public DateTime DateOfBirth { get { if(IsUsable == false) { throw new ArgumentException("ID Number is unusable!", "IDNumber"); } int year = int.Parse(_match.Groups["Year"].Value); // NOTE: Do not optimize by moving these to static, otherwise the calculation may be incorrect // over year changes, especially century changes. int currentCentury = int.Parse(DateTime.Now.Year.ToString().Substring(0, 2) + "00"); int lastCentury = currentCentury - 100; int currentYear = int.Parse(DateTime.Now.Year.ToString().Substring(2, 2)); // If the year is after or at the current YY, then add last century to it, otherwise add // this century. // TODO: YY -> YYYY logic needs thinking about if(year > currentYear) { year += lastCentury; } else { year += currentCentury; } return new DateTime(year, int.Parse(_match.Groups["Month"].Value), int.Parse(_match.Groups["Day"].Value)); } } /// <summary> /// Indicates the gender for the ID number. /// </summary> /// <exception cref="System.ArgumentException">Thrown if the ID Number is not usable.</exception> public PersonGender Gender { get { if(IsUsable == false) { throw new ArgumentException("ID Number is unusable!", "IDNumber"); } int gender = int.Parse(_match.Groups["Gender"].Value); if(gender < (int) PersonGender.Male) { return PersonGender.Female; } else { return PersonGender.Male; } } } /// <summary> /// Indicates the citizenship for the ID number. /// </summary> /// <exception cref="System.ArgumentException">Thrown if the ID Number is not usable.</exception> public PersonCitizenship Citizenship { get { if(IsUsable == false) { throw new ArgumentException("ID Number is unusable!", "IDNumber"); } return (PersonCitizenship) Enum.Parse(typeof(PersonCitizenship), _match.Groups["Citizenship"].Value); } } /// <summary> /// Indicates if the IDNumber is usable or not. /// </summary> public bool IsUsable { get { return _match.Success; } } /// <summary> /// Indicates if the IDNumber is valid or not. /// </summary> public bool IsValid { get { if(IsUsable == true) { // Calculate total A by adding the figures in the odd positions i.e. the first, third, fifth, // seventh, ninth and eleventh digits. int a = int.Parse(_match.Value.Substring(0, 1)) + int.Parse(_match.Value.Substring(2, 1)) + int.Parse(_match.Value.Substring(4, 1)) + int.Parse(_match.Value.Substring(6, 1)) + int.Parse(_match.Value.Substring(8, 1)) + int.Parse(_match.Value.Substring(10, 1)); // Calculate total B by taking the even figures of the number as a whole number, and then // multiplying that number by 2, and then add the individual figures together. int b = int.Parse(_match.Value.Substring(1, 1) + _match.Value.Substring(3, 1) + _match.Value.Substring(5, 1) + _match.Value.Substring(7, 1) + _match.Value.Substring(9, 1) + _match.Value.Substring(11, 1)); b *= 2; string bString = b.ToString(); b = 0; for(int index = 0; index < bString.Length; index++) { b += int.Parse(bString.Substring(index, 1)); } // Calculate total C by adding total A to total B. int c = a + b; // The control-figure can now be determined by subtracting the ones in figure C from 10. string cString = c.ToString() ; cString = cString.Substring(cString.Length - 1, 1) ; int control = 0; // Where the total C is a multiple of 10, the control figure will be 0. if(cString != "0") { control = 10 - int.Parse(cString.Substring(cString.Length - 1, 1)); } if(_match.Groups["Control"].Value == control.ToString()) { return true; } } return false; } } #endregion } } Here is the code from my default.aspx.cs page: using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using Utilities.Southafrica; <- this is the one i added to public partial class _Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { var someNumber = new IdentityNumber("123456"); <- gives error } } Can someone please tell the syntax for how I pass an id number to the class? Thanks

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• how to pass an id number string to this class (asp.net, c#)

  - by Phil

  I'm very much a vb person, but have had to use this id number class in c#. I got it from http://www.codingsanity.com/idnumber.htm : using System; using System.Text.RegularExpressions; namespace Utilities.SouthAfrica { /// <summary> /// Represents a South African Identity Number. /// valid number = 7707215230080 /// invalid test number = 1234567891234 /// /// </summary> [Serializable()] public class IdentityNumber { #region Enumerations /// <summary> /// Indicates a gender. /// </summary> public enum PersonGender { Female = 0, Male = 5 } public enum PersonCitizenship { SouthAfrican = 0, Foreign = 1 } #endregion #region Declarations static Regex _expression; Match _match; const string _IDExpression = @"(?<Year>[0-9][0-9])(?<Month>([0][1-9])|([1][0-2]))(?<Day>([0-2][0-9])|([3][0-1]))(?<Gender>[0-9])(?<Series>[0-9]{3})(?<Citizenship>[0-9])(?<Uniform>[0-9])(?<Control>[0-9])"; #endregion #region Constuctors /// <summary> /// Sets up the shared objects for ID validation. /// </summary> static IdentityNumber() { _expression = new Regex(_IDExpression, RegexOptions.Compiled | RegexOptions.Singleline); } /// <summary> /// Creates the ID number from a string. /// </summary> /// <param name="IDNumber">The string ID number.</param> public IdentityNumber(string IDNumber) { _match = _expression.Match(IDNumber.Trim()); } #endregion #region Properties /// <summary> /// Indicates the date of birth encoded in the ID Number. /// </summary> /// <exception cref="System.ArgumentException">Thrown if the ID Number is not usable.</exception> public DateTime DateOfBirth { get { if(IsUsable == false) { throw new ArgumentException("ID Number is unusable!", "IDNumber"); } int year = int.Parse(_match.Groups["Year"].Value); // NOTE: Do not optimize by moving these to static, otherwise the calculation may be incorrect // over year changes, especially century changes. int currentCentury = int.Parse(DateTime.Now.Year.ToString().Substring(0, 2) + "00"); int lastCentury = currentCentury - 100; int currentYear = int.Parse(DateTime.Now.Year.ToString().Substring(2, 2)); // If the year is after or at the current YY, then add last century to it, otherwise add // this century. // TODO: YY -> YYYY logic needs thinking about if(year > currentYear) { year += lastCentury; } else { year += currentCentury; } return new DateTime(year, int.Parse(_match.Groups["Month"].Value), int.Parse(_match.Groups["Day"].Value)); } } /// <summary> /// Indicates the gender for the ID number. /// </summary> /// <exception cref="System.ArgumentException">Thrown if the ID Number is not usable.</exception> public PersonGender Gender { get { if(IsUsable == false) { throw new ArgumentException("ID Number is unusable!", "IDNumber"); } int gender = int.Parse(_match.Groups["Gender"].Value); if(gender < (int) PersonGender.Male) { return PersonGender.Female; } else { return PersonGender.Male; } } } /// <summary> /// Indicates the citizenship for the ID number. /// </summary> /// <exception cref="System.ArgumentException">Thrown if the ID Number is not usable.</exception> public PersonCitizenship Citizenship { get { if(IsUsable == false) { throw new ArgumentException("ID Number is unusable!", "IDNumber"); } return (PersonCitizenship) Enum.Parse(typeof(PersonCitizenship), _match.Groups["Citizenship"].Value); } } /// <summary> /// Indicates if the IDNumber is usable or not. /// </summary> public bool IsUsable { get { return _match.Success; } } /// <summary> /// Indicates if the IDNumber is valid or not. /// </summary> public bool IsValid { get { if(IsUsable == true) { // Calculate total A by adding the figures in the odd positions i.e. the first, third, fifth, // seventh, ninth and eleventh digits. int a = int.Parse(_match.Value.Substring(0, 1)) + int.Parse(_match.Value.Substring(2, 1)) + int.Parse(_match.Value.Substring(4, 1)) + int.Parse(_match.Value.Substring(6, 1)) + int.Parse(_match.Value.Substring(8, 1)) + int.Parse(_match.Value.Substring(10, 1)); // Calculate total B by taking the even figures of the number as a whole number, and then // multiplying that number by 2, and then add the individual figures together. int b = int.Parse(_match.Value.Substring(1, 1) + _match.Value.Substring(3, 1) + _match.Value.Substring(5, 1) + _match.Value.Substring(7, 1) + _match.Value.Substring(9, 1) + _match.Value.Substring(11, 1)); b *= 2; string bString = b.ToString(); b = 0; for(int index = 0; index < bString.Length; index++) { b += int.Parse(bString.Substring(index, 1)); } // Calculate total C by adding total A to total B. int c = a + b; // The control-figure can now be determined by subtracting the ones in figure C from 10. string cString = c.ToString() ; cString = cString.Substring(cString.Length - 1, 1) ; int control = 0; // Where the total C is a multiple of 10, the control figure will be 0. if(cString != "0") { control = 10 - int.Parse(cString.Substring(cString.Length - 1, 1)); } if(_match.Groups["Control"].Value == control.ToString()) { return true; } } return false; } } #endregion } } Can someone please tell the syntax for how I pass an id number to the class? Thanks

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• SOA PARTNER COMMUNITY NEWSLETTER JULY 2012

  - by mseika

  SOA PARTNER COMMUNITY NEWSLETTER JULY 2012 Dear SOA partner community member To provide our community members the best of our knowledge, we want your feedback on our SOA Partner community. Thus we are organizing SOA Partner Community Survey 2012. We request you to participate in the survey and give your valuable feedback on various areas of marketing, sales and education. To continue our successful BPM Suite, Oracle is launching together with you Process Accelerators initiative. It’s your opportunity to co-develop and market predefined processes. Oracle Fusion Applications Design Patterns are a great tool to develop your SOA or BPM solution or process accelerators. To promote your SOA & BPM Specialization we continue to offer several benefits. This month we would like to highlight our Specialization Plaques - make sure you request one for your office! Our Fusion Middleware Summer Camps are booked out, if could not get a seat you can attend the SOA & BPM track @ Virtual Developer Day: Oracle Fusion Development Oracle demo systems offer´s two new demos: Business Driven Development based on BPM Suite & SOA Lifecycle Management. Jürgen KressOracle SOA & BPM Partner Adoption EMEA NEW CONTENT Community SurveyProcess Accelerators KitPlaques SOA & BPM SpecializedSOA & BPM at Virtual Developer Day News from our Partners & CommunityOverview of SOA Diagnostics in 11.1.1.6 Business driven development(BDD) demo now available! SOA Lifecycle Management Oracle Fusion applications design patterns Updated material by Oracle Connect and Network SOA Blogs SOA on Facebook SOA on LinkedIn SOA on Twitter Mix SOA Forum COMMUNITY SURVEY Like every year we would like to get your feedback in our SOA Partner Community Survey 2012. Make sure that You attend to further develop our community and support our planning! It is key for us to get your feedback to prepare for the next fiscal year. Back to top PROCESS ACCELERATORS KIT Oracle is very interested to co-develop and market with you, our partners, pre-defined processes for BPM Suite.I am very happy to announce a new program called “Oracle BPM Partner Solution Catalog”. This program will provide a one-stop shop for our customers looking for Oracle BPM partner solutions available in the market today.The Oracle BPM Solution Catalog will be hosted on our very popular Oracle Technology Network (OTN). To give you an idea of the scale of customer visibility, OTN today receives over 1Million hits per day from our business and developer community. We would like to invite you to list your Oracle BPM 11g solutions available today.In order to participate in this program, you need to do the following: Fill in the attached slide templates - #3 and #4 for each Oracle BPM 11g solution you would like to list on OTN.Please add links to whitepapers , videos, references to the specific solution in the template slide. We recommend that you create a landing page on your website for these linked artifacts and just point to the same from within the PowerPoint template. This will give you the flexibility to update the information as frequently as needed. If you have the particular solution in production or a reference available, please list them as well. Send the PowerPoint template slides (1 set of slides for each Oracle BPM solution) to [email protected]. In addition to having the opportunity to list your solutions on OTN for Oracle customers, you will have the chance to advertise your new wins/implementations/solutions in an Oracle Sponsored PM Webinar held every quarter. This program is targeted to go live by the end of summer 2012. At this point, we are targeting a soft launch in July end 2012 so send on your BPM solutions information as soon as possible. We would love to have your solution(s) listed in the “Oracle BPM Partner Solution Catalog” at the time of the launch. This will be a live repository so you can keep adding more solutions as they become available. If you have any questions, please feel free to contact us [email protected], Product Strategy Director, Oracle BPM , Phone +1 650.506.5486.Thank you and look forward to hearing from you. Oracle BPM team Process Accelerators Overview.pdf ProcessAcceleratorsDataSheet.pdf Demos draUPK.zip & trmUPK.zip BPM Solution repository slides.ppt Additional BPM material BPM Process Development Lifecycle Document that describes recommended approach to collaborative process modeling across business and IT tools ADF 11g PS5 Application with Customized BPM Worklist Task Flow (MDS Seeded Customization) by Andrejus Baranovskis BPMN process editor problems in 11.1.1.6 by Mark Nelson BPM – Disable DBMS job to refresh B2B Materialized View by Mark Nelson For the complete kit please visit the BPM folder at our SOA Community Workspace (SOA Community membership required). For the complete presentation please visit our SOA Community Workspace (SOA Community membership required). Information is Oracle and Partner confidential! Back to top PLAQUES SOA & BPM SPECIALIZED We continue to offer you a nice SOA & BPM Specialization plaque with your logo to proof your success. If you are a SOA or BPM Specialized partner and would like to request the plaque please send Brigitte an e-mail with the following information: Partner Name Partner logo (preferred eps file) Partner Status gold or platinum Your shipping address Your Specialization: SOA or BPM We recommend to mount the plaque at your office reception in addition you can use the SOA Specialization logos at your website download Logo: Gold & Platinum or the BPM logos Gold & Platinum Back to top SOA & BPM AT VIRTUAL DEVELOPER DAY Register now for this FREE hands-on online workshop Get up to date and learn everything you wanted to know about Oracle ADF & Fusion Development plus live Q&A chats with Oracle technical staffOracle Application Development Framework (ADF) is the standards based, strategic framework for Oracle Fusion Applications and Oracle Fusion Middleware. Oracle ADF’s integration with the Oracle SOA Suite, Oracle WebCenter and Oracle BI creates a complete productive development platform for your custom applications.Join us at this FREE virtual event and learn the latest in Fusion Development including: Is Oracle ADF development faster and simpler than Forms, Apex or .Net? Mobile Application Development with ADF Mobile Oracle ADF development with Eclipse Oracle WebCenter Portal and ADF Development Application Lifecycle Management with ADF Building Process Centric Applications with ADF and BPM Oracle Business Intelligence and ADF Integration Live Q&A chats with Oracle technical staff Developer lead, manager or architect - this event has something for everyone. Don’t miss this opportunity.Tuesday, July 10, 2012. 9:00 a.m. PT -1:00 p.m. PT 11:00 a.m. CT - 3:00 p.m. CT 12:00 p.m. ET - 4:00 p.m. ET 1:00 p.m. BRT - 5:00 p.m. BRT Register online now! for this FREE event. Agenda: 09:00 am Opening 09:30 am Keynote: Oracle Fusion Development Track1Introduction to Fusion Development Track2What's New in Fusion Development Track3Fusion Development in the Enterprise 10:00 am Is Oracle ADF Development Faster and Simpler than Oracle Forms, APEX or .Net? Mobile Application Development with ADF Mobile Oracle WebCenter Portal and ADF Development 11:00 am Rich Web UI made simple - an ADF Faces Overview Oracle Enterprise Pack for Eclipse - ADF Development Building Process Centric Applications with ADF and BPM 12:00 noon Next Generation Controller for JSF Application Lifecycle Management for ADF Oracle Business Intelligence and ADF Integration *Hands On Lab – WebCenter and ADF Lab w/ JDeveloper - Lab materials will be provided ahead of the event to give you ample time to work through the lab and increase the productivity of the live chat sessions the day of the event. Sessions abstractsRegister online now! for this FREE event Read more on Community Events and post your comment here. Back to top NEWS FROM OUR PARTNERS AND COMMUNITY Send your tweets @soacommunity #soacommunity and follow us at http://twitter.com/soacommunity JDeveloper & ADF?Troubleshooting BPMN process editor problems in 11.1.1.6http://dlvr.it/1p0FfS SOA Community?SOA & BPM @ Virtual Developer Day: Oracle Fusion Development - July 10th 2012https://soacommunity.wordpress.com/2012/07/02/soa-bpm-virtual-developer-day- oracle-fusion-developmentjuly-10th-2012/#soacommunity #soa #bom #education orclateamsoa ?A-Team Blog #ateam: BAM design pointers - In working recently with a large Oracle customer on SOA and BAM, I discove.http://ow.ly/1kYqES SOA CommunitySOA Community Newsletter June 2012http://wp.me/p10C8u-qw SOA CommunityBPMN process editor problems in 11.1.1.6 by Mark Nelsonhttp://redstack.wordpress.com/2012/06/27/ bpmn-process-editor-problems-in-11-1-1-6 #soacommunity #bpm OTNArchBeat ?SOA Learning Library: free short, topic-focused training on Oracle SOA & BPM products | @SOACommunity http://pub.vitrue.com/NE1G Andrejus Baranovskis ?ADF 11g PS5 Application with Customized BPM Worklist Task Flow (MDS Seeded Customization)http://fb.me/1coX4r1X1 SOA CommunitySOA Learning Library provides a comprehensive curriculum for the SOA and BPM product suites https://soacommunity.wordpress.com/2012/06/27/soa-learning-library #soacommunity #soa #bpm OTNArchBeat ?A Universal JMX Client for Weblogic - Part 1: Monitoring BPEL Thread Pools in SOA 11g | Stefan Koserhttp://pub.vitrue.com/mQVZ OTNArchBeat ?BPM - Disable DBMS job to refresh B2B Materialized View | Mark Nelson http://pub.vitrue.com/3PR0Oracle SOA ?Learn how Choice Hotels Implements Innovative Google Maps Solution with #OracleSOA http://bit.ly/MTwIJ3 SOA Communitytop Tweets SOA Partner Community - June 2012 Send your tweets @soacommunity #soacommunity https://soacommunity.wordpress.com/2012/06/25/top-tweets-soa-partner-community-june-2012 Torsten Winterberg#OPITZ is pushing Oracle commitment to the next level: New Specializations done: ADF, BPM, WLS, Exadatahttp://bit.ly/KX1WVS ServiceTechSymposium ?Only 8 more days left until Super Early Bird Registration Discount expires! http://www.servicetechsymposium.com OracleBlogsSOA Management in 3 minutes - Video explainerhttp://ow.ly/1kN5pn SOA Community ?SOA, Cloud & Service Technology Symposium 2012 London - Enter Promo Code: Djmxz370https://soacommunity.wordpress.com/2012/06/22/soa-cloud-service-technology-symposium-2012-london #soasymposium #soacommunity #soa Heidi BuelowGreat course! w David Read RT @soacommunity: product management ADF for BPM training 5 seats left https://soacommunity.wordpress.com/2012/06/12/fusion-middleware-summer-campsadvanced-partner-trainings/ #bpm #soacommunity SOA Community ?product management ADF for BPM training 5 seats lefthttps://soacommunity.wordpress.com/2012/06/12/fusion-middleware-summer-campsadvanced-partner-trainings/ #bpm #soacommunity OTNArchBeat ?Oacle Fusion Applications Design Patterns Now Available For Developers | Ultan O'Broinhttp://pub.vitrue.com/UEiF OTNArchBeat ?SOA, Cloud & Service Technology Symposium 2012London - Special Oracle Discounthttp://pub.vitrue.com/8E0J SOA CommunityBecome a facebook fan of soacommunity http://www.facebook.com/soacommunity #soacommunity SOA Community ?SOA Suite HealthCare Integration Architecture https://blogs.oracle.com/SOAForHealthcare/entry/soa_suite_healthcare_integration_architecture #soacommunity #soa Andrejus Baranovskis ?Running Pre-built Virtual Machine for SOA Suite and BPM Suite 11g PS5 on Mac OS X Snow Leopard (10.6http://fb.me/vB8nO0Vg OracleBlogsPrinciples of Service-Oriented Architecture by Douwe P. van den Bos http://ow.ly/1kIcOP OTNArchBeatOracle Public Cloud Architecture | @TylerJewell http://ow.ly/bHAcL The SOA Network ?Business Process Management, Service-Oriented Architecture, and Web 2.0: Business Transformation or.http://bit.ly/LBgREL #ITNews #SOA OracleBlogs ?Oracle SOA Foundation Practitioner Certificationhttp://ow.ly/1kGYYg Frank Nimphius ?Learn Advanced ADF. ORACLE Fusion Middleware Summer Camps in Lisbon - July 9th - 13thhttp://bit.ly/KGCl3i SOA CommunityTransform Your Application Integration with Best Practices from Oracle Customershttps://blogs.oracle.com/SOA/entry/transform_your_application_integration_with #soacommunity #soa #bpm Simone GeibWhat you always wanted to know about #oraclesoa diagnostics: Shawn Bailey, Overview of SOA Diagnostics in 11.1.1.6,http://ow.ly/bxK0M Oracle SOA ?Save the date: Jun 21 10AM, SOA & BPM Customer Insight Series. Hear how Choice Hotels went from legacy to #oraclesoa http://bit.ly/LsNDGl OTNArchBeat ?New VirtualBox images for Oracle SOA Suite & Oracle BPM Suite 11.1.1.6.0http://ow.ly/bwDAl OracleBlogs ?Process development lifecycle in Oracle BPM 11g http://ow.ly/1ktesY Daniel AmadeiNew post: Oracle BPEL 11g Message Delivery & Recovery.http://amadei.com.br/blog/index.php /oracle-bpel-11g-message-delivery SOA Community ?Sending out the June edition of the #soacommunity newsletter - read it or become a member http://www.oracle.com/goto/emea/soa!#soa #bpm Arun Pareek ?For the past six months Ahmed Aboulnaga and me have been working on Oracle SOA Suite 11g Administrator's Handbook.http://lnkd.in/CAvpUQ SOA CommunitySun shine all day no clouds - solar eclipse is over... #sunshine #cloud http://www.infoq.com/presentations/Swarm-Computing Michel SchildmeijerWatch my blog Oracle Service Bus 11g: listing projects and services with WLST - part 1 http://lnkd.in/B7f3GQ @TITAN_GS @wlscommunity OTNArchBeatBook Review: Oracle Application Integration Architecture (AIA) Foundation Pack 11gR1: Essentials | Rajesh Rahejahttp://ow.ly/bn2cc OTNArchBeat ?Driving from Business Architecture to Business Process Services | @vghariharan http://ow.ly/bn5UB OTNArchBeat ?SOA Analysis within the Department of Defense Architecture Framework (DoDAF) 2.0 - Part II | Dawit Lessanu http://ow.ly/bn6sX Simone Geib ?Contact me directly for ideas how to improvehttp://bit.ly/advancedsoasuite and additional posts, presentations, white papers, ... #soasuite Simone Geib ?#soasuite advanced OTN page has become too cluttered. Broke it into separate pages to start with. http://bit.ly/advancedsoasuite OracleBlogs ?June Webcast: SOA Gateway Implementation and Troubleshooting (2 sessions) http://ow.ly/1kbRFA ServiceTechSymposium ?New session just posted to calendar: "NoSQL for Data Services, Data Virtualization & Big Data" by Guido Schmutz, Trivadis AG ://ow.ly/bjjOeDebra Lilley ?looks good - real proof people are using the apps ! RT @fteter: Very cool Fusion Applications Help site: http://bit.ly/L3nvOR #FusionApps demed ?rapid proliferation of cloud computing will drive convergence of SOA and cloud paradigms" http://ovum.com/2012/05/18/soa-paves-the-way-for-cloud/ SOA CommunityMiddleware Oracle Excellence Awards 2012-HAPPY NEW YEAR! https://soacommunity.wordpress.com/2012/05/31/middleware-oracle-excellence-awards-2012happy-new-year/ #soacommunity #opn #opnaward #specialization #oracle SOA CommunityHappy New Year #soacommunity thanks for the business! Time for a drink http://pic.twitter.com/zkK08KWB OTNArchBeat ?Who should ‘own’ the Enterprise Architecture? | Michael Glas http://bit.ly/K0ge0Q SOA Communitytop Tweets SOA Partner Community &ndash; May 2012 http://wp.me/p10C8u-pP ServiceTechSymposiumNew session just posted to Symposium calendar: "Elastic SOA in the Cloud" by Steve Millidge, C2B2 Consulting http://www.servicetechsymposium.com/agenda2012.php #elastic_soa_in_the_cloud orclateamsoa ?A-Team Blog #ateam: How to Set JVM Parameters in Oracle SOA 11Ghttp://ow.ly/1k2cnl ServiceTechSymposium ?New session just posted to Symposium calendar: "SOA Governance at EDP: A Global Energy Company" by Manuel Rosa, Linkhttp://www.servicetechsymposium.com/agenda2012.php#soa_governance_at_edp SOA Community ?VirtualBox image SOA Suite & BPM Suite 11.1.1.6.0&ndash;Your feedback?http://wp.me/p10C8u-qh Oracle MiddlewareSave the date: Jun 21 10AM, SOA & BPM Customer Insight Series. Hear how Choice Hotels went from legacy to#oraclesoa http://bit.ly/LU1y5N OTNArchBeat ?Goodbye, Silos. Hello SOA. | @stephanieoverbyhttp://pub.vitrue.com/NJJO SOA CommunityBPM Standard Edition - to start your BPM project http://wp.me/p10C8u-qj Please feel free to send us your news! And add your blog to our SOA blog wiki. Back to top OVERVIEW OF SOA DIAGNOSTICS IN 11.1.1.6 What tools are available for diagnosing SOA Suite issues? There are a variety of tools available to help you and Support diagnose SOA Suite issues in 11g but it can be confusing as to which tool is appropriate for a particular situation and what their relationships are. This blog post will introduce the various tools and attempt to clarify what each is for and how they are related. Let's first list the tools we'll be addressing: RDA: Remote Diagnostic Agent DFW: Diagnostic Framework Selective Tracing DMS: Dynamic Monitoring Service ODL: Oracle Diagnostic Logging ADR: Automatic Diagnostics Repository ADRCI: Automatic Diagnostics Repository Command Interpreter WLDF: WebLogic Diagnostic Framework This overview is not mean to be a comprehensive guide on using all of these tools, however, extensive reference materials are included that will provide many more details on their execution. Another point to note is that all of these tools are applicable for Fusion Middleware as a whole but specific products may or may not have implemented features to leverage them. A couple of the tools have a WebLogic Scripting Tool or 'WLST' interface. WLST is a command interface for executing pre-built functions and custom scripts against a domain. A detailed WLST tutorial is beyond the scope of this post but you can find general information here. There are more specific resources in the below sections.In this post when we refer to 'Enterprise Manager' or 'EM' we are referring to Enterprise Manager Fusion Middleware Control. read the full blog post here. Read more on Oracle and post your comment here. Back to top BUSINESS DRIVEN DEVELOPMENT (BDD) DEMO NOW AVAILABLE! For access to the Oracle demo systems please visit OPN and talk to your Partner Expert DSS is pleased to announce the availability of the demo “Business Driven Development“. This innovative demonstration uses a case-study approach to show business users how they can easily streamline their Business Processes - delivering greater efficiency, agility, visibility and collaboration with Oracle BPM and WebCenter. The BDD demonstration uses a case study-based approach to highlight a business problem at a fictional company, Avitek Corporation, and uses Oracle BPM and Oracle WebCenter to solve the business problem. This holistic approach has specifically been used to appeal to a non-technical business analyst user. This demo is NOT focused on product features, but aims to guide users through a complete BPM lifecycle. The scenario is based on improving a simple order process (scenario details are in the demo script). Avitek Corporation is sufferinng from a manual email-driven ordering process. Sales reps don’t know where the customer orders are stuck (no visibility) and finance users are unable to manually approve every order (no automation). There are several areas where this process can be improved with Business Process Management technology. This demo shows how improving following areas will ignificantly help resolve the business problems Avitek Corporation is facing. Areas for improvement include: Utilizing BPM for process management, rather than an unregulated, email-based process. Utilizing automated services, rather than requiring a human to key into a system. For example, Finance checking the customer’s credit rating is something that could be automated. Centralizing business rules that can be integrated into a business process, rather than requiring a human to process them. For example, Finance must determine when orders can be automatically approved. Provide insight and visibility into the process. For example, Sales Rep needs to know the status of their customer’s orders. The BDD Demo uses the following products. Oracle BPM Suite 11g PS4FP Oracle WebCenter 11g PS4FP (for Process Spaces) Oracle Business Activity Monitoring 11g Oracle Database 11g Back to top SOA LIFECYCLE MANAGEMENT For access to the Oracle demo systems please visit OPN and talk to your Partner Expert We are pleased to announce the availability of the SOA Management demo that showcases some of the key provisioning and lifecycle management capabilities of SOA Management Pack Enterprise Edition (EE). This demo specifically focuses on some of the lifecycle management solutions for Oracle SOA Suite and Oracle Service Bus (OSB). Demo Highlights The demo showcases the following capabilities. Provisioning of SOA Composites Provisioning of OSB Projects Provision SOA and OSB artifacts in a future maintenance window Back to top ORACLE FUSION APPLICATIONS DESIGN PATTERNS The Oracle Fusion Applications user experience design patterns are published! These new, reusable usability solutions and best-practices, which will join the Oracle dashboard patterns and guidelines that are already available online, are used by Oracle to artfully bring to life a new standard in the user experience, or UX, of enterprise applications. Now, the Oracle applications development community can benefit from the science behind the Oracle Fusion Applications user experience, too. These Oracle Fusion Applications UX Design Patterns, or blueprints, enable Oracle applications developers and system implementers everywhere to leverage professional usability insight when: tailoring an Oracle Fusion application, creating coexistence solutions that existing users will be delighted with, thus enabling graceful user transitions to Oracle Fusion Applications down the road, or designing exciting, new, highly usable applications in the cloud or on-premise. Based on the Oracle Application Development Framework (ADF) components, the Oracle Fusion Applications patterns and guidelines are proven with real users and in the Applications UX usability labs, so you can get right to work coding productivity-enhancing designs that provide an advantage for your entire business. What’s the best way to get started? We’ve made that easy, too. The Design Filter Tool (DeFT) selects the best pattern for your user type and task. Simply adapt your selection for your own task flow and content, and you’re on your way to a really great applications user experience. More Oracle applications design patterns and training are coming your way in the future. To provide feedback on the sets that are currently available, let me know in the comments! Read more on Fusionapps and post your comment here. Back to top UPDATED ORACLE MATERIAL Integrated SOA Gateway Documentation - Implementation Guide | Developer’s Guide Webcast Series: Oracle’s SOA and Oracle Business Process Management Solutions (Choice Hotels, Eaton, Farmers Insurance) BAM design pointers By Kavitha Srinivasan Seeking Oracle Fusion Middleware Go Live StoriesOracle Fusion Middleware product management is looking for recent go live stories to share with the Oracle sales team, sales consulting, product management and other internal groups. Customer contact details may remain anonymous. Your successful implementation will be featured in a quarterly report. The chance to present on an internal webcast is also available. Contact Maria Forney ([email protected]) if you have a noteworthy implementation success story. This is a good opportunity for partners interested in showcasing Oracle Fusion Middleware implementations, and gaining more exposure within Oracle. Performance tuning resources. All in one: docs, blogs, WPs, ppts: http://bit.ly/soa_resources Back to top HAVE YOU MISSED OUR LAST SOA PARTNER COMMUNITY WEBCASTS? UPK Webcast Business Driven Application Management & BPM11g & Application Grid & GoldenGate & Fusion Middleware Pricing & OC4J to WebLogic & Next Generation SOA & Fusion Middleware in Utility & Fusion Middleware in Communications & Fusion Middleware in Public Services & Fusion Middleware in Financial Services Please check your local OPN trainings calendar for additional training dates and locations. Back to top SOA PARTNER COMMUNITY CALENDAR On-Demand Trainings Event Name Language Type SOA Virtual Developers Day English Tech In-Class Trainings Date Event name Location / Country Contact person Type 09-13.07.2012 BPM Suite 11g advanced training by David Read Lisbon, Portugal Jürgen Kress Tech 09-13.07.2012 ADF 11g advanced training by Grant Ronald and Frank Nimphius Lisbon, Portugal Jürgen Kress Tech 09-13.07.2012 WebCenter Portal advanced training by Stefan Krantz and Angelo Santagata Lisbon, Portugal Jürgen Kress Tech 10.07.2012 Fusion Middleware Virtual Developer Day Online OTN Tech 10- 12.07.2012 WebLogic 12c training by Cosmin Tudor Lisbon, Portugal Jürgen Kress Tech 16-18.07.2012 SOA Suite 11g advanced training by Niall Commiskey Munich, Germany Jürgen Kress Tech 16-18.07.2012 ADF for BPM Suite 11g advanced training by David Read Munich, Germany Jürgen Kress Tech 16-18.07.2012 WebCenter Sites 11g advanced training by Product Management Munich, Germany Jürgen Kress Tech 17-20.07.2012 Oracle BPM 11g Implementation Bootcamp Live Virtual Class Oracle University Tech 23-26.07.2012 Oracle BPM 11g Implementation Bootcamp Utrecht, Netherlands Oracle University Tech 29-31.08.2012 Oracle BPM 11g Implementation Bootcamp Live Virtual Class Oracle University Tech 02-05.10.2012 Oracle BPM 11g Implementation Bootcamp Utrecht, Netherlands Oracle University Tech 15-18.10.2012 Oracle BPM 11g Implementation Bootcamp Utrecht, Netherlands Oracle University Tech 28-30.11.2012 Oracle AIA 11g Implementation Bootcamp Live Virtual Class Oracle University Tech 11-14.12.2012 Oracle BPM 11g Implementation Bootcamp Live Virtual Class Oracle University Tech 20-22.2.2013 Oracle AIA 11g Implementation Bootcamp Utrecht, Netherlands Oracle University Tech 14-17.1.2013 Oracle BPM 11g Implementation Bootcamp Utrecht, Netherlands Oracle University Tech 15-18.3.2013 Oracle BPM 11g Implementation Bootcamp Utrecht, Netherlands Oracle University Tech Please check your local OPN Training Calendar for additional training and locations here. Back to top SOASCHOOL.COM - SOA CERTIFIED PROFESSIONAL(SOACP) PROGRAM The SOASchool.com - SOA Certified Professional (SOACP) program is dedicated to excellence in the field of SOA and service-oriented computing. Through a series of seasoned course modules and exams, IT professionals have the opportunity to obtain a number of different certifications to recognize their accomplishment of gaining "project ready" SOA proficiency. This comprehensive and strictly vendor-neutral program was developed in cooperation with best-selling SOA author Thomas Erl and several major SOA organizations and academic institutions. Through the involvement of the SOA Education Committee, course contents and certification requirements are constantly reviewed and revised to stay current with developments in the service-oriented computing industry. The program is currently comprised of 12 course modules and 5 certifications and is expanding to 18 course modules and 8 certifications throughout 2009. For more information, visit www.soaschool.com and www.soacp.com. Blog Twitter LinkedIn Mix Forum Wiki Back to top YOUR CONTENT ON THE NEWSLETTER AND ON THE SOA COMMUNITY PORTAL Publishing Your StoriesWe would like to invite our partners to publish information in the newsletter or on our SOA Community portal. Especially we are looking for your real life experience with our SOA technology. Please send your documents to Jürgen Kress. We look forward to getting your suggestions! Back to top SOA DISCUSSION FORUM BECOMES INTERACTIVE AT THE SOA COMMUNITY! Do you want to chat to experts, including partners and Oracle SOA Product Development? Do you want to get the latest information about our SOA solutions and events?Attend our private online SOA Discussion Forum at OTN. Please send your OTN forums user name to Brigitte Felisaz. You must be a registered user to access the SOA Discussion Forum. Back to top INVITE YOUR COLLEAGUES TO JOIN THE SOA COMMUNITY Please feel free to invite your colleagues to join the SOA Community and to participate in the SOA Assessment tests. For registration please login the Oracle PartnerNetwork and go to: www.oracle.com/goto/emea/soa For any questions on the above or concerning SOA and Oracle in general please contact the Oracle EMEA Alliances & Channels SOA Team. Best regardsOracle EMEA SOA TeamJürgen Kress Jürgen KressSOA Partner Adoption EMEATel. +49 89 1430 1479E-Mail: [email protected]

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• Red Gate Coder interviews: Alex Davies

  - by Michael Williamson

  Alex Davies has been a software engineer at Red Gate since graduating from university, and is currently busy working on .NET Demon. We talked about tackling parallel programming with his actors framework, a scientific approach to debugging, and how JavaScript is going to affect the programming languages we use in years to come. So, if we start at the start, how did you get started in programming? When I was seven or eight, I was given a BBC Micro for Christmas. I had asked for a Game Boy, but my dad thought it would be better to give me a proper computer. For a year or so, I only played games on it, but then I found the user guide for writing programs in it. I gradually started doing more stuff on it and found it fun. I liked creating. As I went into senior school I continued to write stuff on there, trying to write games that weren’t very good. I got a real computer when I was fourteen and found ways to write BASIC on it. Visual Basic to start with, and then something more interesting than that. How did you learn to program? Was there someone helping you out? Absolutely not! I learnt out of a book, or by experimenting. I remember the first time I found a loop, I was like “Oh my God! I don’t have to write out the same line over and over and over again any more. It’s amazing!” When did you think this might be something that you actually wanted to do as a career? For a long time, I thought it wasn’t something that you would do as a career, because it was too much fun to be a career. I thought I’d do chemistry at university and some kind of career based on chemical engineering. And then I went to a careers fair at school when I was seventeen or eighteen, and it just didn’t interest me whatsoever. I thought “I could be a programmer, and there’s loads of money there, and I’m good at it, and it’s fun”, but also that I shouldn’t spoil my hobby. Now I don’t really program in my spare time any more, which is a bit of a shame, but I program all the rest of the time, so I can live with it. Do you think you learnt much about programming at university? Yes, definitely! I went into university knowing how to make computers do anything I wanted them to do. However, I didn’t have the language to talk about algorithms, so the algorithms course in my first year was massively important. Learning other language paradigms like functional programming was really good for breadth of understanding. Functional programming influences normal programming through design rather than actually using it all the time. I draw inspiration from it to write imperative programs which I think is actually becoming really fashionable now, but I’ve been doing it for ages. I did it first! There were also some courses on really odd programming languages, a bit of Prolog, a little bit of C. Having a little bit of each of those is something that I would have never done on my own, so it was important. And then there are knowledge-based courses which are about not programming itself but things that have been programmed like TCP. Those are really important for examples for how to approach things. Did you do any internships while you were at university? Yeah, I spent both of my summers at the same company. I thought I could code well before I went there. Looking back at the crap that I produced, it was only surpassed in its crappiness by all of the other code already in that company. I’m so much better at writing nice code now than I used to be back then. Was there just not a culture of looking after your code? There was, they just didn’t hire people for their abilities in that area. They hired people for raw IQ. The first indicator of it going wrong was that they didn’t have any computer scientists, which is a bit odd in a programming company. But even beyond that they didn’t have people who learnt architecture from anyone else. Most of them had started straight out of university, so never really had experience or mentors to learn from. There wasn’t the experience to draw from to teach each other. In the second half of my second internship, I was being given tasks like looking at new technologies and teaching people stuff. Interns shouldn’t be teaching people how to do their jobs! All interns are going to have little nuggets of things that you don’t know about, but they shouldn’t consistently be the ones who know the most. It’s not a good environment to learn. I was going to ask how you found working with people who were more experienced than you… When I reached Red Gate, I found some people who were more experienced programmers than me, and that was difficult. I’ve been coding since I was tiny. At university there were people who were cleverer than me, but there weren’t very many who were more experienced programmers than me. During my internship, I didn’t find anyone who I classed as being a noticeably more experienced programmer than me. So, it was a shock to the system to have valid criticisms rather than just formatting criticisms. However, Red Gate’s not so big on the actual code review, at least it wasn’t when I started. We did an entire product release and then somebody looked over all of the UI of that product which I’d written and say what they didn’t like. By that point, it was way too late and I’d disagree with them. Do you think the lack of code reviews was a bad thing? I think if there’s going to be any oversight of new people, then it should be continuous rather than chunky. For me I don’t mind too much, I could go out and get oversight if I wanted it, and in those situations I felt comfortable without it. If I was managing the new person, then maybe I’d be keener on oversight and then the right way to do it is continuously and in very, very small chunks. Have you had any significant projects you’ve worked on outside of a job? When I was a teenager I wrote all sorts of stuff. I used to write games, I derived how to do isomorphic projections myself once. I didn’t know what the word was so I couldn’t Google for it, so I worked it out myself. It was horrifically complicated. But it sort of tailed off when I started at university, and is now basically zero. If I do side-projects now, they tend to be work-related side projects like my actors framework, NAct, which I started in a down tools week. Could you explain a little more about NAct? It is a little C# framework for writing parallel code more easily. Parallel programming is difficult when you need to write to shared data. Sometimes parallel programming is easy because you don’t need to write to shared data. When you do need to access shared data, you could just have your threads pile in and do their work, but then you would screw up the data because the threads would trample on each other’s toes. You could lock, but locks are really dangerous if you’re using more than one of them. You get interactions like deadlocks, and that’s just nasty. Actors instead allows you to say this piece of data belongs to this thread of execution, and nobody else can read it. If you want to read it, then ask that thread of execution for a piece of it by sending a message, and it will send the data back by a message. And that avoids deadlocks as long as you follow some obvious rules about not making your actors sit around waiting for other actors to do something. There are lots of ways to write actors, NAct allows you to do it as if it was method calls on other objects, which means you get all the strong type-safety that C# programmers like. Do you think that this is suitable for the majority of parallel programming, or do you think it’s only suitable for specific cases? It’s suitable for most difficult parallel programming. If you’ve just got a hundred web requests which are all independent of each other, then I wouldn’t bother because it’s easier to just spin them up in separate threads and they can proceed independently of each other. But where you’ve got difficult parallel programming, where you’ve got multiple threads accessing multiple bits of data in multiple ways at different times, then actors is at least as good as all other ways, and is, I reckon, easier to think about. When you’re using actors, you presumably still have to write your code in a different way from you would otherwise using single-threaded code. You can’t use actors with any methods that have return types, because you’re not allowed to call into another actor and wait for it. If you want to get a piece of data out of another actor, then you’ve got to use tasks so that you can use “async” and “await” to await asynchronously for it. But other than that, you can still stick things in classes so it’s not too different really. Rather than having thousands of objects with mutable state, you can use component-orientated design, where there are only a few mutable classes which each have a small number of instances. Then there can be thousands of immutable objects. If you tend to do that anyway, then actors isn’t much of a jump. If I’ve already built my system without any parallelism, how hard is it to add actors to exploit all eight cores on my desktop? Usually pretty easy. If you can identify even one boundary where things look like messages and you have components where some objects live on one side and these other objects live on the other side, then you can have a granddaddy object on one side be an actor and it will parallelise as it goes across that boundary. Not too difficult. If we do get 1000-core desktop PCs, do you think actors will scale up? It’s hard. There are always in the order of twenty to fifty actors in my whole program because I tend to write each component as actors, and I tend to have one instance of each component. So this won’t scale to a thousand cores. What you can do is write data structures out of actors. I use dictionaries all over the place, and if you need a dictionary that is going to be accessed concurrently, then you could build one of those out of actors in no time. You can use queuing to marshal requests between different slices of the dictionary which are living on different threads. So it’s like a distributed hash table but all of the chunks of it are on the same machine. That means that each of these thousand processors has cached one small piece of the dictionary. I reckon it wouldn’t be too big a leap to start doing proper parallelism. Do you think it helps if actors get baked into the language, similarly to Erlang? Erlang is excellent in that it has thread-local garbage collection. C# doesn’t, so there’s a limit to how well C# actors can possibly scale because there’s a single garbage collected heap shared between all of them. When you do a global garbage collection, you’ve got to stop all of the actors, which is seriously expensive, whereas in Erlang garbage collections happen per-actor, so they’re insanely cheap. However, Erlang deviated from all the sensible language design that people have used recently and has just come up with crazy stuff. You can definitely retrofit thread-local garbage collection to .NET, and then it’s quite well-suited to support actors, even if it’s not baked into the language. Speaking of language design, do you have a favourite programming language? I’ll choose a language which I’ve never written before. I like the idea of Scala. It sounds like C#, only with some of the niggles gone. I enjoy writing static types. It means you don’t have to writing tests so much. When you say it doesn’t have some of the niggles? C# doesn’t allow the use of a property as a method group. It doesn’t have Scala case classes, or sum types, where you can do a switch statement and the compiler checks that you’ve checked all the cases, which is really useful in functional-style programming. Pattern-matching, in other words. That’s actually the major niggle. C# is pretty good, and I’m quite happy with C#. And what about going even further with the type system to remove the need for tests to something like Haskell? Or is that a step too far? I’m quite a pragmatist, I don’t think I could deal with trying to write big systems in languages with too few other users, especially when learning how to structure things. I just don’t know anyone who can teach me, and the Internet won’t teach me. That’s the main reason I wouldn’t use it. If I turned up at a company that writes big systems in Haskell, I would have no objection to that, but I wouldn’t instigate it. What about things in C#? For instance, there’s contracts in C#, so you can try to statically verify a bit more about your code. Do you think that’s useful, or just not worthwhile? I’ve not really tried it. My hunch is that it needs to be built into the language and be quite mathematical for it to work in real life, and that doesn’t seem to have ended up true for C# contracts. I don’t think anyone who’s tried them thinks they’re any good. I might be wrong. On a slightly different note, how do you like to debug code? I think I’m quite an odd debugger. I use guesswork extremely rarely, especially if something seems quite difficult to debug. I’ve been bitten spending hours and hours on guesswork and not being scientific about debugging in the past, so now I’m scientific to a fault. What I want is to see the bug happening in the debugger, to step through the bug happening. To watch the program going from a valid state to an invalid state. When there’s a bug and I can’t work out why it’s happening, I try to find some piece of evidence which places the bug in one section of the code. From that experiment, I binary chop on the possible causes of the bug. I suppose that means binary chopping on places in the code, or binary chopping on a stage through a processing cycle. Basically, I’m very stupid about how I debug. I won’t make any guesses, I won’t use any intuition, I will only identify the experiment that’s going to binary chop most effectively and repeat rather than trying to guess anything. I suppose it’s quite top-down. Is most of the time then spent in the debugger? Absolutely, if at all possible I will never debug using print statements or logs. I don’t really hold much stock in outputting logs. If there’s any bug which can be reproduced locally, I’d rather do it in the debugger than outputting logs. And with SmartAssembly error reporting, there’s not a lot that can’t be either observed in an error report and just fixed, or reproduced locally. And in those other situations, maybe I’ll use logs. But I hate using logs. You stare at the log, trying to guess what’s going on, and that’s exactly what I don’t like doing. You have to just look at it and see does this look right or wrong. We’ve covered how you get to grip with bugs. How do you get to grips with an entire codebase? I watch it in the debugger. I find little bugs and then try to fix them, and mostly do it by watching them in the debugger and gradually getting an understanding of how the code works using my process of binary chopping. I have to do a lot of reading and watching code to choose where my slicing-in-half experiment is going to be. The last time I did it was SmartAssembly. The old code was a complete mess, but at least it did things top to bottom. There wasn’t too much of some of the big abstractions where flow of control goes all over the place, into a base class and back again. Code’s really hard to understand when that happens. So I like to choose a little bug and try to fix it, and choose a bigger bug and try to fix it. Definitely learn by doing. I want to always have an aim so that I get a little achievement after every few hours of debugging. Once I’ve learnt the codebase I might be able to fix all the bugs in an hour, but I’d rather be using them as an aim while I’m learning the codebase. If I was a maintainer of a codebase, what should I do to make it as easy as possible for you to understand? Keep distinct concepts in different places. And name your stuff so that it’s obvious which concepts live there. You shouldn’t have some variable that gets set miles up the top of somewhere, and then is read miles down to choose some later behaviour. I’m talking from a very much SmartAssembly point of view because the old SmartAssembly codebase had tons and tons of these things, where it would read some property of the code and then deal with it later. Just thousands of variables in scope. Loads of things to think about. If you can keep concepts separate, then it aids me in my process of fixing bugs one at a time, because each bug is going to more or less be understandable in the one place where it is. And what about tests? Do you think they help at all? I’ve never had the opportunity to learn a codebase which has had tests, I don’t know what it’s like! What about when you’re actually developing? How useful do you find tests in finding bugs or regressions? Finding regressions, absolutely. Running bits of code that would be quite hard to run otherwise, definitely. It doesn’t happen very often that a test finds a bug in the first place. I don’t really buy nebulous promises like tests being a good way to think about the spec of the code. My thinking goes something like “This code works at the moment, great, ship it! Ah, there’s a way that this code doesn’t work. Okay, write a test, demonstrate that it doesn’t work, fix it, use the test to demonstrate that it’s now fixed, and keep the test for future regressions.” The most valuable tests are for bugs that have actually happened at some point, because bugs that have actually happened at some point, despite the fact that you think you’ve fixed them, are way more likely to appear again than new bugs are. Does that mean that when you write your code the first time, there are no tests? Often. The chance of there being a bug in a new feature is relatively unaffected by whether I’ve written a test for that new feature because I’m not good enough at writing tests to think of bugs that I would have written into the code. So not writing regression tests for all of your code hasn’t affected you too badly? There are different kinds of features. Some of them just always work, and are just not flaky, they just continue working whatever you throw at them. Maybe because the type-checker is particularly effective around them. Writing tests for those features which just tend to always work is a waste of time. And because it’s a waste of time I’ll tend to wait until a feature has demonstrated its flakiness by having bugs in it before I start trying to test it. You can get a feel for whether it’s going to be flaky code as you’re writing it. I try to write it to make it not flaky, but there are some things that are just inherently flaky. And very occasionally, I’ll think “this is going to be flaky” as I’m writing, and then maybe do a test, but not most of the time. How do you think your programming style has changed over time? I’ve got clearer about what the right way of doing things is. I used to flip-flop a lot between different ideas. Five years ago I came up with some really good ideas and some really terrible ideas. All of them seemed great when I thought of them, but they were quite diverse ideas, whereas now I have a smaller set of reliable ideas that are actually good for structuring code. So my code is probably more similar to itself than it used to be back in the day, when I was trying stuff out. I’ve got more disciplined about encapsulation, I think. There are operational things like I use actors more now than I used to, and that forces me to use immutability more than I used to. The first code that I wrote in Red Gate was the memory profiler UI, and that was an actor, I just didn’t know the name of it at the time. I don’t really use object-orientation. By object-orientation, I mean having n objects of the same type which are mutable. I want a constant number of objects that are mutable, and they should be different types. I stick stuff in dictionaries and then have one thing that owns the dictionary and puts stuff in and out of it. That’s definitely a pattern that I’ve seen recently. I think maybe I’m doing functional programming. Possibly. It’s plausible. If you had to summarise the essence of programming in a pithy sentence, how would you do it? Programming is the form of art that, without losing any of the beauty of architecture or fine art, allows you to produce things that people love and you make money from. So you think it’s an art rather than a science? It’s a little bit of engineering, a smidgeon of maths, but it’s not science. Like architecture, programming is on that boundary between art and engineering. If you want to do it really nicely, it’s mostly art. You can get away with doing architecture and programming entirely by having a good engineering mind, but you’re not going to produce anything nice. You’re not going to have joy doing it if you’re an engineering mind. Architects who are just engineering minds are not going to enjoy their job. I suppose engineering is the foundation on which you build the art. Exactly. How do you think programming is going to change over the next ten years? There will be an unfortunate shift towards dynamically-typed languages, because of JavaScript. JavaScript has an unfair advantage. JavaScript’s unfair advantage will cause more people to be exposed to dynamically-typed languages, which means other dynamically-typed languages crop up and the best features go into dynamically-typed languages. Then people conflate the good features with the fact that it’s dynamically-typed, and more investment goes into dynamically-typed languages. They end up better, so people use them. What about the idea of compiling other languages, possibly statically-typed, to JavaScript? It’s a reasonable idea. I would like to do it, but I don’t think enough people in the world are going to do it to make it pick up. The hordes of beginners are the lifeblood of a language community. They are what makes there be good tools and what makes there be vibrant community websites. And any particular thing which is the same as JavaScript only with extra stuff added to it, although it might be technically great, is not going to have the hordes of beginners. JavaScript is always to be quickest and easiest way for a beginner to start programming in the browser. And dynamically-typed languages are great for beginners. Compilers are pretty scary and beginners don’t write big code. And having your errors come up in the same place, whether they’re statically checkable errors or not, is quite nice for a beginner. If someone asked me to teach them some programming, I’d teach them JavaScript. If dynamically-typed languages are great for beginners, when do you think the benefits of static typing start to kick in? The value of having a statically typed program is in the tools that rely on the static types to produce a smooth IDE experience rather than actually telling me my compile errors. And only once you’re experienced enough a programmer that having a really smooth IDE experience makes a blind bit of difference, does static typing make a blind bit of difference. So it’s not really about size of codebase. If I go and write up a tiny program, I’m still going to get value out of writing it in C# using ReSharper because I’m experienced with C# and ReSharper enough to be able to write code five times faster if I have that help. Any other visions of the future? Nobody’s going to use actors. Because everyone’s going to be running on single-core VMs connected over network-ready protocols like JSON over HTTP. So, parallelism within one operating system is going to die. But until then, you should use actors. More Red Gater Coder interviews

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• Data Modeling: Logical Modeling Exercise

  - by swisscheese

  In trying to learn the art of data storage I have been trying to take in as much solid information as possible. PerformanceDBA posted some really helpful tutorials/examples in the following posts among others: is my data normalized? and Relational table naming convention. I already asked a subset question of this model here. So to make sure I understood the concepts he presented and I have seen elsewhere I wanted to take things a step or two further and see if I am grasping the concepts. Hence the purpose of this post, which hopefully others can also learn from. Everything I present is conceptual to me and for learning rather than applying it in some production system. It would be cool to get some input from PerformanceDBA also since I used his models to get started, but I appreciate all input given from anyone. As I am new to databases and especially modeling I will be the first to admit that I may not always ask the right questions, explain my thoughts clearly, or use the right verbage due to lack of expertise on the subject. So please keep that in mind and feel free to steer me in the right direction if I head off track. If there is enough interest in this I would like to take this from the logical to physical phases to show the evolution of the process and share it here on Stack. I will keep this thread for the Logical Diagram though and start new one for the additional steps. For my understanding I will be building a MySQL DB in the end to run some tests and see if what I came up with actually works. Here is the list of things that I want to capture in this conceptual model. Edit for V1.2 The purpose of this is to list Bands, their members, and the Events that they will be appearing at, as well as offer music and other merchandise for sale Members will be able to match up with friends Members can write reviews on the Bands, their music, and their events. There can only be one review per member on a given item, although they can edit their reviews and history will be maintained. BandMembers will have the chance to write a single Comment on Reviews about the Band they are associated with. Collectively as a Band only one Comment is allowed per Review. Members can then rate all Reviews and Comments but only once per given instance Members can select their favorite Bands, music, Merchandise, and Events Bands, Songs, and Events will be categorized into the type of Genre that they are and then further subcategorized into a SubGenre if necessary. It is ok for a Band or Event to fall into more then one Genre/SubGenre combination. Event date, time, and location will be posted for a given band and members can show that they will be attending the Event. An Event can be comprised of more than one Band, and multiple Events can take place at a single location on the same day Every party will be tied to at least one address and address history shall be maintained. Each party could also be tied to more then one address at a time (i.e. billing, shipping, physical) There will be stored profiles for Bands, BandMembers, and general members. So there it is, maybe a bit involved but could be a great learning tool for many hopefully as the process evolves and input is given by the community. Any input? EDIT v1.1 In response to PerformanceDBA U.3) That means no merchandise other than Band merchandise in the database. Correct ? That was my original thought but you got me thinking. Maybe the site would want to sell its own merchandise or even other merchandise from the bands. Not sure a mod to make for that. Would it require an entire rework of the Catalog section or just the identifying relationship that exists with the Band? Attempted a mod to sell both complete albums or song. Either way they would both be in electronic format only available for download. That is why I listed an Album as being comprised of Songs rather then 2 separate entities. U.5) I understand what you bring up about the circular relation with Favorite. I would like to get to this “It is either one Entity with some form of differentiation (FavoriteType) which identifies its treatment” but how to is not clear to me. What am I missing here? u.6) “Business Rules This is probably the only area you are weak in.” Thanks for the honest response. I will readdress these but I hope to clear up some confusion in my head first with the responses I have posted back to you. Q.1) Yes I would like to have Accepted, Rejected, and Blocked. I am not sure what you are referring to as to how this would change the logical model? Q.2) A person does not have to be a User. They can exist only as a BandMember. Is that what you are asking? Minor Issue Zero, One, or More…Oops I admit I forgot to give this attention when building the model. I am submitting this version as is and will address in a future version. I need to read up more on Constraint Checking to make sure I am understanding things. M.4) Depends if you envision OrderPurchase in the future. Can you expand as to what you mean here? EDIT V1.2 In response to PerformanceDBA input... Lessons learned. I was mixing the concept of Identifying / Non-Identifying and Cardinality (i.e. Genre / SubGenre), and doing so inconsistently to make things worse. Associative Tables are not required in Logical Diagrams as their many-to-many relationships can be depicted and then expanded in the Physical Model. I was overlooking the Cardinality in a lot of the relationships The importance of reading through relationships using effective Verb Phrases to reassure I am modeling what I want to accomplish. U.2) In the concept of this model it is only required to track a Venue as a location for an Event. No further data needs to be collected. With that being said Events will take place on a given EventDate and will be hosted at a Venue. Venues will host multiple events and possibly multiple events on a given date. In my new model my thinking was that EventDate is already tied to Event . Therefore, Venue will not need a relationship with EventDate. The 5th and 6th bullets you have listed under U.2) leave me questioning my thinking though. Am I missing something here? U.3) Is it time to move the link between Item and Band up to Item and Party instead? With the current design I don't see a possibility to sell merchandise not tied to the band as you have brought up. U.5) I left as per your input rather than making it a discrete Supertype/Subtype Relationship as I don’t see a benefit of having that type of roll up. Additional Revisions AR.1) After going through the exercise for FavoriteItem, I feel that Item to Review requires a many-to-many relationship so that is indicated. Necessary? Ok here we go for v1.3 I took a few days on this version, going back and forth with my design. Once the logical process is complete, as I want to see if I am on the right track, I will go through in depth what I had learned and the troubles I faced as a beginner going through this process. The big point for this version was it took throwing in some Keys to help see what I was missing in the past. Going through the process of doing a matrix proved to be of great help also. Regardless of anything, if it wasn't for the input given by PerformanceDBA I would still be a lost soul wondering in the dark. Who knows my current design might reaffirm that I still am, but I have learned a lot so I am know I at least have a flashlight in my hand. At this point in time I admit that I am still confused about identifying and non-identifying relationships. In my model I had to use non-identifying relationships with non nulls just to join the relationships I wanted to model. In reading a lot on the subject there seems to be a lot of disagreement and indecisiveness on the subject so I did what I thought represented the right things in my model. When to force (identifying) and when to be free (non-identifying)? Anyone have inputs? EDIT V1.4 Ok took the V1.3 inputs and cleaned things up for this V1.4 Currently working on a V1.5 to include attributes.

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