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• Great event : Microsoft Visual Studio 2010 Launch @ Microsoft TechEd Blore

  - by sathya

  Great event : Microsoft Visual Studio 2010 Launch @ Microsoft TechEd Blore   I was really excited on attending the day 1 of Microsoft TechEd 2010 in Bangalore. This is the first Teched that am attending. The event was really fun filled with lot of knowledge sharing sessions and lots of goodies and gifts by the partners Initially the Event Started by Murthy's Session. He explained about the Developers relating to the 5 elements of nature (Pancha Boothaas) 1. Fire - Passion 2. Wave (Water) - Catch the right wave which we need to apply. 3. Earth - Connections and lots of opportunities around the world 4. Air -  Its whatever we breathe. Developers.. Without them nothing is possible. they are like the air 5. Sky - Cloud based applications   Next the Keynote and the announcement of Visual Studio by SomaSegar. List of things that he delivered his speech on : 1. Announcement of Visual Studio 2010 2. Announcement of .NET 4.0 3. Announcement of Silverlight later this week 4. What is the current Trend? Microsoft has done a research with many developers across the globe and have got the following feedback from the users. Get Lost (interrupted) - When we do some work and somebody is calling or interrepting by someother way we lose track of what we were doing and we need to do from the start Falling Behind- Technology gets updated  phenomenally over a period of time and developers always have a scenario like they are not in the state of the art technology and they always have a doubt whether they are staying updated. Lack of Collobaration - When a Manager asks a person what the team members have done and some might be done and some might not be and finally all are into a state like we dont know where we are. So they have addressed these 3 points in the VS 2010 by the following features : Get Lost - Some cool features which could overcome this. We have some Graphical interface. which could show what we have done and where we are. Some Zoom features in the code level. Falling Behind - Everything is based on .NET language base. 2010 has been built in such a way that if developers know the native language that's enough for building good applications. Lack of Collobaration - Some Dashboard Features which would show where exactly the project is. And a graphical user interface is shown on clicking which it directly drills down even to the code level. 5. An overview on all new features in VS 2010. 6. Some good demos of new features in VS 2010 by Polita and one more girl. Some of the new features included : 1. Team Explorer 2. Zoom in Code 3. Ribbon Development 4. Development in Single Platform for Windows Phone, XBox, Zune, Azure, Web Based and Windows based applications 5. Sequence Diagram Generation directly from code 6. Dashboards to show project status 7. Javascript and JQuery intellisense 8. Native support for JQuery 9. Packaging feature while deploying. 10. Generation of different versions of web.config like Web.Config.Production, Web.Config.Staging, etc. 11. IntelliTrace - Eliminating the "Not Reproducible" statement. 12. Automated User Interface Testing. At last in the closing of the day we had a great event called Demo Extravaganza, where lot of cool projects that were launched by Microsoft and also the projects that are under research were also shown. I got a lot of info about Bing today. BING really rocks!!! It has the following : 1. Visual Search 2. Product based search. For each product different menu filters were provided to make an advanced search 3. BING Maps was awesome!! It zoomed in to the street level and we can assume that we are the persons who are walking or running on the road and we can see the real objects like buildings moving by our side. 4. PhotoSynth was used in BING to show up all the images taken around the globe in a 3D format. 5. Formula - If we give some formula it automatically gives the value for the variable or derivation of expression Also some info about some kool touch apps which does an authentication and computation of Teched Attendee's Points that they have scored and the sessions attended. One guy won an XBOX in lucky draw as a gift. There were lot of Partner Stalls like Accenture,Intel,Citrix,MicroFocus,Telerik,infragistics,Sapient etc. Some Offers were provided for us like 50% off on Certifications, 1 free Elearning Course, etc. Stay tuned!! Wil update you on other events too..

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• SOA Suite 11g Dynamic Payload Testing with soapUI Free Edition

  - by Greg Mally

  Overview Many web service developers use soapUI for various tests like: smoke test, unit test, and load testing because you can get a free edition that is fairly robust. However, if you need to venture into more complex testing that requires a dynamic payload, then the free edition doesn't necessarily make it easy. This feature does exist in soapUI, but for obvious reasons it is in the Pro version. In this blog I will show you how to use soapUI free edition for dynamic payloads in a simplified example. Hopefully this will open the doors for you to expand into more complex scenarios. The following assumes that you have a working knowledge of soapUI and will not go into concepts like setting up a project etc. For the basics, please review the documentation for soapUI: http://www.soapui.org/Getting-Started/. Additionally, we will be using asynchronous web services and you can review the setup for this in my blog: SOA Suite 11g Asynchronous Testing with soapUI. Features in soapUI Free Edition Relating to this Topic The soapUI test tool provides a very feature rich environment that can do many things provided you are willing to go beyond point and click. For this example, we will be leveraging just a couple features for our dynamic payload example: Test Case Properties Scripting with Groovy Basically, we will be using a property as a global variable and we will manipulate that property using a Groovy script. Setting Up Our Property Properties are available throughout soapUI and here is a snippet from the soapUI website defining the locations: Projects : for handling Project scope values, for example a subscription ID TestSuite : for handling TestSuite scoped values, can be seen as "arguments" to a TestSuite TestCases : for handling TestCase scoped values, can be seen as "arguments" to a TestCase Properties TestStep : for providing local values/state within a TestCase Local TestStep properties : several TestStep types maintain their own list of properties specific to their functionality : DataSource, DataSink, Run TestCase MockServices : for handling MockService scoped values/arguments MockResponses : for handling MockResponse scoped values Global Properties : for handling Global properties, optionally from an external source For our example, we will be defining a custom property in a TestCase called SimpleAsyncPayload. The property can be created in either the Custom Properties tab located at the bottom of the Navigator panel when the TestCase is selected in the Navigator or the Properties label in the TestCase editor: Navigator Panel TestCase Editor You will notice that I set a value of “0” for the custom property. For this simplified example, we will need to retrieve that value and manipulate it prior to making the web service request invocation. In order to accomplish this, we will need to get Groovy ;) Let's Get Groovy We will now add a new Groovy Script step to the TestCase called Manipulate Payload: TestCase Editor > Append Step > Groovy Script Once we have added the Groovy Script step to our TestCase, we can open the Groovy Script editor to add the code to: Get the current value of the property we created called SimpleAsyncPayload. Convert the value of the property to an integer. Increment the value. Store the incremented value back into the TestCase property called SimpleAsyncPayload. The script should look something like the following: Groovy Script Editor – Manipulate Payload At this point we can test the script to see if it is working by simply running the TestCase (left-click on the green triangle in the upper left-hand corner of the TestCase editor). To verify if it ran correctly, we can look at the value of the SimpleAsyncPayload property which should now be 1: TestCase Editor – Run Results All that is left to complete the TestCase is to append another step of type Test Request. The information required to append the request is a name and an operation to invoke. In this example we will use the default name and select the SimpleAsyncBPELProcessBingd -> process as the operation (any other information being requested, simply use the defaults unless you are calling an asynchronous operation then do not add any assertions). We are now in familiar ground with the Test Request editor. Depending upon the type of operation you are invoking (synchronous or asynchronous), please update the request with the necessary information (e.g., callback information for asynchronous operations). We will now tweak the Test Request payload to retrieve the value of the SimpleAsyncPayload property. The soapUI editor makes this very simple: right-click in the payload and navigate to the property (e.g., right-click > Get Data.. > TestCase: [Groovy TestCase] > Property [SimpleAsyncPayload]): Test Request Editor – Insert Property Value Your payload should now look something like the following: Test Request Editor – Inserted Property Value Just like before, we are now ready to run the TestCase. If everything goes as expected we should see a response like the following: Message Viewer – Results of TestCase Run We are now setup to be able to run a stress test where the payload will change for each request. This simple example can be expanded to include multiple payload values, complex calculations in the scripts, or whatever can be done via the soapUI scripting. Hopefully you have found this useful and happy testing to you :)

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• Red Gate in the Community

  - by Nick Harrison

  Much has been said recently about Red Gate's community involvement and commitment to the DotNet community. Much of this has been unduly negative. Before you start throwing stones and spewing obscenities, consider some additional facts: Red Gate's software is actually very good. I have worked on many projects where Red Gate's software was instrumental in finishing successfully. Red Gate is VERY good to the community. I have spoken at many user groups and code camps where Red Gate has been a sponsor. Red Gate consistently offers up money to pay for the venue or food, and they will often give away licenses as door prizes. There are many such community events that would not take place without Red Gate's support. All I have ever seen them ask for is to have their products mentioned or be listed as a sponsor. They don't insist on anyone following a specific script. They don't monitor how their products are showcased. They let their products speak for themselves. Red Gate sponsors the Simple Talk web site. I publish there regularly. Red Gate has never exerted editorial pressure on me. No one has ever told me we can't publish this unless you mention Red Gate products. No one has ever said, you need to say nice things about Red Gate products in order to be published. They have told me, "you need to make this less academic, so you don't alienate too many readers. "You need to actually write an introduction so people will know what you are talking about". "You need to write this so that someone who isn't a reflection nut will follow what you are trying to say." In short, they have been good editors worried about the quality of the content and what the readers are likely to be interested in. For me personally, Red Gate and Simple Talk have both been excellent to work with. As for the developer outrage… I am a little embarrassed by so much of the response that I am seeing. So much of the complaints remind me of little children whining "but you promised" Semantics aside. A promise is just a promise. It's not like they "pinky sweared". Sadly no amount name calling or "double dog daring" will change the economics of the situation. Red Gate is not a multibillion dollar corporation. They are a mid size company doing the best they can. Without a doubt, their pockets are not as deep as Microsoft's. I honestly believe that they did try to make the "freemium" model work. Sadly it did not. I have no doubt that they intended for it to work and that they tried to make it work. I also have no doubt that they labored over making this decision. This could not have been an easy decision to make. Many people are gleefully proclaiming a massive backlash against Red Gate swearing off their wonderful products and promising to bash them at every opportunity from now on. This is childish behavior that does not represent professionals. This type of behavior is more in line with bullies in the school yard than professionals in a professional community. Now for my own prediction… This back lash against Red Gate is not likely to last very long. We will all realize that we still need their products. We may look around for alternatives, but realize that they really do have the best in class for every product that they produce, and that they really are not exorbitantly priced. We will see them sponsoring Code Camps and User Groups and be reminded, "hey this isn't such a bad company". On the other hand, software shops like Red Gate, will remember this back lash and give a second thought to supporting open source projects. They will worry about getting involved when an individual wants to turn over control for a product that they developed but can no longer support alone. Who wants to run the risk of not being able to follow through on their best intentions. In the end we may all suffer, even the toddlers among us throwing the temper tantrum, "BUT YOU PROMISED!" Disclaimer Before anyone asks or jumps to conclusions, I do not get paid by Red Gate to say any of this. I have often written about their products, and I have long thought that they are a wonderful company with amazing products. If they ever open an office in the SE United States, I will be one of the first to apply.

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• Upgrading SSIS Custom Components for SQL Server 2012

  Having finally got around to upgrading my custom components to SQL Server 2012, I thought I’d share some notes on the process. One of the goals was minimal duplication, so the same code files are used to build the 2008 and 2012 components, I just have a separate project file. The high level steps are listed below, followed by some more details. Create a 2012 copy of the project file Upgrade project, just open the new project file is VS2010 Change target framework to .NET 4.0 Set conditional compilation symbol for DENALI Change any conditional code, including assembly version and UI type name Edit project file to change referenced assemblies for 2012 Change target framework to .NET 4.0 Open the project properties. On the Applications page, change the Target framework to .NET Framework 4. Set conditional compilation symbol for DENALI Re-open the project properties. On the Build tab, first change the Configuration to All Configurations, then set a Conditional compilation symbol of DENALI. Change any conditional code, including assembly version and UI type name The value doesn’t have to be DENALI, it can actually be anything you like, that is just what I use. It is how I control sections of code that vary between versions. There were several API changes between 2005 and 2008, as well as interface name changes. Whilst we don’t have the same issues between 2008 and 2012, I still have some sections of code that do change such as the assembly attributes. #if DENALI [assembly: AssemblyDescription("Data Generator Source for SQL Server Integration Services 2012")] [assembly: AssemblyCopyright("Copyright © 2012 Konesans Ltd")] [assembly: AssemblyVersion("3.0.0.0")] #else [assembly: AssemblyDescription("Data Generator Source for SQL Server Integration Services 2008")] [assembly: AssemblyCopyright("Copyright © 2008 Konesans Ltd")] [assembly: AssemblyVersion("2.0.0.0")] #endif The Visual Studio editor automatically formats the code based on the current compilation symbols, hence in this case the 2008 code is grey to indicate it is disabled. As you can see in the previous example I have distinct assembly version attributes, ensuring I can run both 2008 and 2012 versions of my component side by side. For custom components with a user interface, be sure to update the UITypeName property of the DtsTask or DtsPipelineComponent attributes. As above I use the conditional compilation symbol to control the code. #if DENALI [DtsTask ( DisplayName = "File Watcher Task", Description = "File Watcher Task", IconResource = "Konesans.Dts.Tasks.FileWatcherTask.FileWatcherTask.ico", UITypeName = "Konesans.Dts.Tasks.FileWatcherTask.FileWatcherTaskUI,Konesans.Dts.Tasks.FileWatcherTask,Version=3.0.0.0,Culture=Neutral,PublicKeyToken=b2ab4a111192992b", TaskContact = "File Watcher Task; Konesans Ltd; Copyright © 2012 Konesans Ltd; http://www.konesans.com" )] #else [DtsTask ( DisplayName = "File Watcher Task", Description = "File Watcher Task", IconResource = "Konesans.Dts.Tasks.FileWatcherTask.FileWatcherTask.ico", UITypeName = "Konesans.Dts.Tasks.FileWatcherTask.FileWatcherTaskUI,Konesans.Dts.Tasks.FileWatcherTask,Version=2.0.0.0,Culture=Neutral,PublicKeyToken=b2ab4a111192992b", TaskContact = "File Watcher Task; Konesans Ltd; Copyright © 2004-2008 Konesans Ltd; http://www.konesans.com" )] #endif public sealed class FileWatcherTask: Task, IDTSComponentPersist, IDTSBreakpointSite, IDTSSuspend { // .. code goes on... } Shown below is another example I found that needed changing. I borrow one of the MS editors, and use it against a custom property, but need to ensure I reference the correct version of the MS controls assembly. This section of code is actually shared between the 2005, 2008 and 2012 versions of my component hence it has test for both DENALI and KATMAI symbols. #if DENALI const string multiLineUI = "Microsoft.DataTransformationServices.Controls.ModalMultilineStringEditor, Microsoft.DataTransformationServices.Controls, Version=11.0.00.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91"; #elif KATMAI const string multiLineUI = "Microsoft.DataTransformationServices.Controls.ModalMultilineStringEditor, Microsoft.DataTransformationServices.Controls, Version=10.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91"; #else const string multiLineUI = "Microsoft.DataTransformationServices.Controls.ModalMultilineStringEditor, Microsoft.DataTransformationServices.Controls, Version=9.0.242.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91"; #endif // Create Match Expression parameter IDTSCustomPropertyCollection100 propertyCollection = outputColumn.CustomPropertyCollection; IDTSCustomProperty100 property = propertyCollection.New(); property = propertyCollection.New(); property.Name = MatchParams.Name; property.Description = MatchParams.Description; property.TypeConverter = typeof(MultilineStringConverter).AssemblyQualifiedName; property.UITypeEditor = multiLineUI; property.Value = MatchParams.DefaultValue; Edit project file to change referenced assemblies for 2012 We now need to edit the project file itself. Open the MyComponente2012.cproj  in you favourite text editor, and then perform a couple of find and replaces as listed below: Find Replace Comment Version=10.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91 Version=11.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91 Change the assembly references version from SQL Server 2008 to SQL Server 2012. Microsoft SQL Server\100\ Microsoft SQL Server\110\ Change any assembly reference hint path locations from from SQL Server 2008 to SQL Server 2012. If you use any Build Events during development, such as copying the component assembly to the DTS folder, or calling GACUTIL to install it into the GAC, you can also change these now. An example of my new post-build event for a pipeline component is shown below, which uses the .NET 4.0 path for GACUTIL. It also uses the 110 folder location, instead of 100 for SQL Server 2008, but that was covered the the previous find and replace. "C:\Program Files (x86)\Microsoft SDKs\Windows\v7.0A\Bin\NETFX 4.0 Tools\gacutil.exe" /if "$(TargetPath)" copy "$(TargetPath)" "%ProgramFiles%\Microsoft SQL Server\110\DTS\PipelineComponents" /Y

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• C# async and actors

  - by Alex.Davies

  If you read my last post about async, you might be wondering what drove me to write such odd code in the first place. The short answer is that .NET Demon is written using NAct Actors. Actors are an old idea, which I believe deserve a renaissance under C# 5. The idea is to isolate each stateful object so that only one thread has access to its state at any point in time. That much should be familiar, it's equivalent to traditional lock-based synchronization. The different part is that actors pass "messages" to each other rather than calling a method and waiting for it to return. By doing that, each thread can only ever be holding one lock. This completely eliminates deadlocks, my least favourite concurrency problem. Most people who use actors take this quite literally, and there are plenty of frameworks which help you to create message classes and loops which can receive the messages, inspect what type of message they are, and process them accordingly. But I write C# for a reason. Do I really have to choose between using actors and everything I love about object orientation in C#? Type safety Interfaces Inheritance Generics As it turns out, no. You don't need to choose between messages and method calls. A method call makes a perfectly good message, as long as you don't wait for it to return. This is where asynchonous methods come in. I have used NAct for a while to wrap my objects in a proxy layer. As long as I followed the rule that methods must always return void, NAct queued up the call for later, and immediately released my thread. When I needed to get information out of other actors, I could use EventHandlers and callbacks (continuation passing style, for any CS geeks reading), and NAct would call me back in my isolated thread without blocking the actor that raised the event. Using callbacks looks horrible though. To remind you: m_BuildControl.FilterEnabledForBuilding(    projects,    enabledProjects = m_OutOfDateProjectFinder.FilterNeedsBuilding(        enabledProjects,             newDirtyProjects =             {                 ....... Which is why I'm really happy that NAct now supports async methods. Now, methods are allowed to return Task rather than just void. I can await those methods, and C# 5 will turn the rest of my method into a continuation for me. NAct will run the other method in the other actor's context, but will make sure that when my method resumes, we're back in my context. Neither actor was ever blocked waiting for the other one. Apart from when they were actually busy doing something, they were responsive to concurrent messages from other sources. To be fair, you could use async methods with lock statements to achieve exactly the same thing, but it's ugly. Here's a realistic example of an object that has a queue of data that gets passed to another object to be processed: class QueueProcessor {    private readonly ItemProcessor m_ItemProcessor = ...     private readonly object m_Sync = new object();    private Queue<object> m_DataQueue = ...    private List<object> m_Results = ...     public async Task ProcessOne() {         object data = null;         lock (m_Sync)         {             data = m_DataQueue.Dequeue();         }         var processedData = await m_ItemProcessor.ProcessData(data); lock (m_Sync)         {             m_Results.Add(processedData);         }     } } We needed to write two lock blocks, one to get the data to process, one to store the result. The worrying part is how easily we could have forgotten one of the locks. Compare that to the version using NAct: class QueueProcessorActor : IActor { private readonly ItemProcessor m_ItemProcessor = ... private Queue<object> m_DataQueue = ... private List<object> m_Results = ... public async Task ProcessOne()     {         // We are an actor, it's always thread-safe to access our private fields         var data = m_DataQueue.Dequeue();         var processedData = await m_ItemProcessor.ProcessData(data);         m_Results.Add(processedData);     } } You don't have to explicitly lock anywhere, NAct ensures that your code will only ever run on one thread, because it's an actor. Either way, async is definitely better than traditional synchronous code. Here's a diagram of what a typical synchronous implementation might do: The left side shows what is running on the thread that has the lock required to access the QueueProcessor's data. The red section is where that lock is held, but doesn't need to be. Contrast that with the async version we wrote above: Here, the lock is released in the middle. The QueueProcessor is free to do something else. Most importantly, even if the ItemProcessor sometimes calls the QueueProcessor, they can never deadlock waiting for each other. So I thoroughly recommend you use async for all code that has to wait a while for things. And if you find yourself writing lots of lock statements, think about using actors as well. Using actors and async together really takes the misery out of concurrent programming.

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• Fun With the Chrome JavaScript Console and the Pluralsight Website

  - by Steve Michelotti

  Originally posted on: http://geekswithblogs.net/michelotti/archive/2013/07/24/fun-with-the-chrome-javascript-console-and-the-pluralsight-website.aspxI’m currently working on my third course for Pluralsight. Everyone already knows that Scott Allen is a “dominating force” for Pluralsight but I was curious how many courses other authors have published as well. The Pluralsight Authors page - http://pluralsight.com/training/Authors – shows all 146 authors and you can click on any author’s page to see how many (and which) courses they have authored. The problem is: I don’t want to have to click into 146 pages to get a count for each author. With this in mind, I figured I could write a little JavaScript using the Chrome JavaScript console to do some “detective work.” My first step was to figure out how the HTML was structured on this page so I could do some screen-scraping. Right-click the first author - “Inspect Element”. I can see there is a primary <div> with a class of “main” which contains all the authors. Each author is in an <h3> with an <a> tag containing their name and link to their page:     This web page already has jQuery loaded so I can use $ directly from the console. This allows me to just use jQuery to inspect items on the current page. Notice this is a multi-line command. In order to use multiple lines in the console you have to press SHIFT-ENTER to go to the next line:     Now I can see I’m extracting data just fine. At this point I want to follow each URL. Then I want to screen-scrape this next page to see how many courses each author has done. Let’s take a look at the author detail page:       I can see we have a table (with a css class of “course”) that contains rows for each course authored. This means I can get the number of courses pretty easily like this:     Now I can put this all together. Back on the authors page, I want to follow each URL, extract the returned HTML, and grab the count. In the code below, I simply use the jQuery $.get() method to get the author detail page and the “data” variable that is in the callback contains the HTML. A nice feature of jQuery is that I can simply put this HTML string inside of $() and I can use jQuery selectors directly on it in conjunction with the find() method:     Now I’m getting somewhere. I have every Pluralsight author and how many courses each one has authored. But that’s not quite what I’m after – what I want to see are the authors that have the MOST courses in the library. What I’d like to do is to put all of the data in an array and then sort that array descending by number of courses. I can add an item to the array after each author detail page is returned but the catch here is that I can’t perform the sort operation until ALL of the author detail pages have executed. The jQuery $.get() method is naturally an async method so I essentially have 146 async calls and I don’t want to perform my sort action until ALL have completed (side note: don’t run this script too many times or the Pluralsight servers might think your an evil hacker attempting a DoS attack and deny you). My C# brain wants to use a WaitHandle WaitAll() method here but this is JavaScript. I was able to do this by using the jQuery Deferred() object. I create a new deferred object for each request and push it onto a deferred array. After each request is complete, I signal completion by calling the resolve() method. Finally, I use a $.when.apply() method to execute my descending sort operation once all requests are complete. Here is my complete console command: 1: var authorList = [], 2: defList = []; 3: $(".main h3 a").each(function() { 4: var def = $.Deferred(); 5: defList.push(def); 6: var authorName = $(this).text(); 7: var authorUrl = $(this).attr('href'); 8: $.get(authorUrl, function(data) { 9: var courseCount = $(data).find("table.course tbody tr").length; 10: authorList.push({ name: authorName, numberOfCourses: courseCount }); 11: def.resolve(); 12: }); 13: }); 14: $.when.apply($, defList).then(function() { 15: console.log("*Everything* is complete"); 16: var sortedList = authorList.sort(function(obj1, obj2) { 17: return obj2.numberOfCourses - obj1.numberOfCourses; 18: }); 19: for (var i = 0; i < sortedList.length; i++) { 20: console.log(authorList[i]); 21: } 22: });   And here are the results:     WOW! John Sonmez has 44 courses!! And Matt Milner has 29! I guess Scott Allen isn’t the only “dominating force”. I would have assumed Scott Allen was #1 but he comes in as #3 in total course count (of course Scott has 11 courses in the Top 50, and 14 in the Top 100 which is incredible!). Given that I’m in the middle of producing only my third course, I better get to work!

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• WIF, ADFS 2 and WCF&ndash;Part 6: Chaining multiple Token Services

  - by Your DisplayName here!

  See the previous posts first. So far we looked at the (simpler) scenario where a client acquires a token from an identity provider and uses that for authentication against a relying party WCF service. Another common scenario is, that the client first requests a token from an identity provider, and then uses this token to request a new token from a Resource STS or a partner’s federation gateway. This sounds complicated, but is actually very easy to achieve using WIF’s WS-Trust client support. The sequence is like this: Request a token from an identity provider. You use some “bootstrap” credential for that like Windows integrated, UserName or a client certificate. The realm used for this request is the identifier of the Resource STS/federation gateway. Use the resulting token to request a new token from the Resource STS/federation gateway. The realm for this request would be the ultimate service you want to talk to. Use this resulting token to authenticate against the ultimate service. Step 1 is very much the same as the code I have shown in the last post. In the following snippet, I use a client certificate to get a token from my STS: private static SecurityToken GetIdPToken() {     var factory = new WSTrustChannelFactory(         new CertificateWSTrustBinding(SecurityMode.TransportWithMessageCredential,         idpEndpoint);     factory.TrustVersion = TrustVersion.WSTrust13;       factory.Credentials.ClientCertificate.SetCertificate(         StoreLocation.CurrentUser,         StoreName.My,         X509FindType.FindBySubjectDistinguishedName,         "CN=Client");       var rst = new RequestSecurityToken     {         RequestType = RequestTypes.Issue,         AppliesTo = new EndpointAddress(rstsRealm),         KeyType = KeyTypes.Symmetric     };       var channel = factory.CreateChannel();     return channel.Issue(rst); } To use a token to request another token is slightly different. First the IssuedTokenWSTrustBinding is used and second the channel factory extension methods are used to send the identity provider token to the Resource STS: private static SecurityToken GetRSTSToken(SecurityToken idpToken) {     var binding = new IssuedTokenWSTrustBinding();     binding.SecurityMode = SecurityMode.TransportWithMessageCredential;       var factory = new WSTrustChannelFactory(         binding,         rstsEndpoint);     factory.TrustVersion = TrustVersion.WSTrust13;     factory.Credentials.SupportInteractive = false;       var rst = new RequestSecurityToken     {         RequestType = RequestTypes.Issue,         AppliesTo = new EndpointAddress(svcRealm),         KeyType = KeyTypes.Symmetric     };       factory.ConfigureChannelFactory();     var channel = factory.CreateChannelWithIssuedToken(idpToken);     return channel.Issue(rst); } For this particular case I chose an ADFS endpoint for issued token authentication (see part 1 for more background). Calling the service now works exactly like I described in my last post. You may now wonder if the same thing can be also achieved using configuration only – absolutely. But there are some gotchas. First of all the configuration files becomes quite complex. As we discussed in part 4, the bindings must be nested for WCF to unwind the token call-stack. But in this case svcutil cannot resolve the first hop since it cannot use metadata to inspect the identity provider. This binding must be supplied manually. The other issue is around the value for the realm/appliesTo when requesting a token for the R-STS. Using the manual approach you have full control over that parameter and you can simply use the R-STS issuer URI. Using the configuration approach, the exact address of the R-STS endpoint will be used. This means that you may have to register multiple R-STS endpoints in the identity provider. Another issue you will run into is, that ADFS does only accepts its configured issuer URI as a known realm by default. You’d have to manually add more audience URIs for the specific endpoints using the ADFS Powershell commandlets. I prefer the “manual” approach. That’s it. Hope this is useful information.

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• Common usecases and techniques when integrating a 3rd party application with Oracle Sales Cloud

  - by asantaga

  Over the last year or so I've see a lot of partners migrating and integrate their applications with Oracle Sales Cloud. Interestingly I'd say 60% of the partners use the same set of design patterns over and over again. Most of the time I see that they want to embed their application into Oracle Sales Cloud, within a tab usually, perhaps click on a link to their application (passing some piece of data + credentials) and then within their application update sales cloud again using webservices. Here are some examples of the different use-cases I've seen , and how partners are embedding their applications into Sales Cloud, NB : The following examples use the "Desktop" User Interface rather than the Newer "Simplified User Interface", I'll update the sample application soon but the integration patterns are precisely the same Use Case 1 :  Navigator "Link out" to third party application This is an example of where the developer has added a link to the global navigator and this links out to the 3rd Party Application. Typically one doesn't pass any contextual data with the exception of perhaps user credentials, or better still JWT Token. Techniques Used   Adding Link to Menu Item Using JWT Token in Sales Cloud Use Case 2 : Application Embedded within the Sales Cloud Dashboard Within the Oracle Sales Cloud application there is a tab called "Sales", within this tab its possible to embed a SubTab and embed a iFrame pointing to your application. To do this the developer simply needs to edit the page in customization mode, add the tab and then add the iFrame, simples! The developer can pass credentials/JWT Token and some other pieces of data but not object data (ie the current OpportunityID etc)  Techniques Used Adding a page to the dashboard  Using JWT Token in Sales Cloud  Use Case 3 : Embedding a Tab and Context Linking out from a Sales Cloud object to the 3rd party application In this usecase the developer embeds two components into Oracle Sales Cloud. The first is a SubTab showing summary data to the user (a quote in our case) and then secondly a hyperlink, (although it could be a button) which when clicked navigates the user to the 3rd party application. In this case the developer almost always passes context specific data (i.e. the opportunityId) and a security token (username password combo or JWT Token). The third party application usually takes the data, perhaps queries more data using the Sales Cloud SOAP/WebService interface and then displays the resulting mashup to the user for further processing. When the user has finished their work in the 3rd party application they normally navigate back to Oracle Sales Cloud using what's called a "DeepLink", ie taking them back to the object [opportunity in our case] they came from. This image visually shows a "Happy Path" a user may follow, and combines linking out to an application , webservice calls and deep linking back to Sales Cloud. Techniques Used Extending a SalesCloud application with a custom button Using JWT Token in Sales Cloud Extending Oracle Sales Cloud [Opportnity] with a custom tab exposing External Content Retrieving Data from Oracle Sales cloud using WebServices Coding some groovy script to generate the URLs required (Doc 1571200.1 on MyOracle Support) DeepLinking to specific Oracle Sales Cloud Pages (Doc 1516151.1 on My Oracle Support) Use-Case 4 :  Server Side processing/synchronization This usecase focuses on the Server Side processing of data, in this case synchronizing data. Here the 3rd party application is running on a "timer", e.g. cron or similar, and when triggered it queries data from Oracle Sales Cloud, then it queries data from the 3rd party application, determines the deltas and then inserts the data where required. Specifically here we are calling Oracle Sales Cloud using SOAP/WebServices and the 3rd party application is being communicated to using the REST API, for Oracle Sales Cloud one would use standard JAX-WS WebService calls and for REST one would use the JAX-RS api and perhap the Jackson api for managing JSON objects.. This is a very common use case and one which specifically lends itself to using the Oracle Java Cloud Service as the ideal application server where to host the mediator between the two applications.  Techniques Used Using JWT Token in Sales Cloud Integrating with the Oracle Java Cloud Service Retrieving Data from Oracle Sales cloud using WebServices General Resources The above is just a small set of techniques and use-cases which are used today. There are plenty of other sources of documentation and resources available on the internet but to get you started here are a few of my favourite places  Sales Cloud General Documentation Sales Cloud Customize Tab is useful for general customization of Sales Cloud Sales Cloud Integration Tab focuses on the 3rd party integration techniques  Official Oracle Fusion Developer Relations Blog Official Oracle Fusion Developer Relations YouTube Channel Enjoy integrating! 

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• ASP.NET WebAPI Security 4: Examples for various Authentication Scenarios

  - by Your DisplayName here!

  The Thinktecture.IdentityModel.Http repository includes a number of samples for the various authentication scenarios. All the clients follow a basic pattern: Acquire client credential (a single token, multiple tokens, username/password). Call Service. The service simply enumerates the claims it finds on the request and returns them to the client. I won’t show that part of the code, but rather focus on the step 1 and 2. Basic Authentication This is the most basic (pun inteneded) scenario. My library contains a class that can create the Basic Authentication header value. Simply set username and password and you are good to go. var client = new HttpClient { BaseAddress = _baseAddress }; client.DefaultRequestHeaders.Authorization = new BasicAuthenticationHeaderValue("alice", "alice"); var response = client.GetAsync("identity").Result; response.EnsureSuccessStatusCode();   SAML Authentication To integrate a Web API with an existing enterprise identity provider like ADFS, you can use SAML tokens. This is certainly not the most efficient way of calling a “lightweight service” ;) But very useful if that’s what it takes to get the job done. private static string GetIdentityToken() {     var factory = new WSTrustChannelFactory(         new WindowsWSTrustBinding(SecurityMode.Transport),         _idpEndpoint);     factory.TrustVersion = TrustVersion.WSTrust13;     var rst = new RequestSecurityToken     {         RequestType = RequestTypes.Issue,         KeyType = KeyTypes.Bearer,         AppliesTo = new EndpointAddress(Constants.Realm)     };     var token = factory.CreateChannel().Issue(rst) as GenericXmlSecurityToken;     return token.TokenXml.OuterXml; } private static Identity CallService(string saml) {     var client = new HttpClient { BaseAddress = _baseAddress };     client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("SAML", saml);     var response = client.GetAsync("identity").Result;     response.EnsureSuccessStatusCode();     return response.Content.ReadAsAsync<Identity>().Result; }   SAML to SWT conversion using the Azure Access Control Service Another possible options for integrating SAML based identity providers is to use an intermediary service that allows converting the SAML token to the more compact SWT (Simple Web Token) format. This way you only need to roundtrip the SAML once and can use the SWT afterwards. The code for the conversion uses the ACS OAuth2 endpoint. The OAuth2Client class is part of my library. private static string GetServiceTokenOAuth2(string samlToken) {     var client = new OAuth2Client(_acsOAuth2Endpoint);     return client.RequestAccessTokenAssertion(         samlToken,         SecurityTokenTypes.Saml2TokenProfile11,         Constants.Realm).AccessToken; }   SWT Authentication When you have an identity provider that directly supports a (simple) web token, you can acquire the token directly without the conversion step. Thinktecture.IdentityServer e.g. supports the OAuth2 resource owner credential profile to issue SWT tokens. private static string GetIdentityToken() {     var client = new OAuth2Client(_oauth2Address);     var response = client.RequestAccessTokenUserName("bob", "abc!123", Constants.Realm);     return response.AccessToken; } private static Identity CallService(string swt) {     var client = new HttpClient { BaseAddress = _baseAddress };     client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", swt);     var response = client.GetAsync("identity").Result;     response.EnsureSuccessStatusCode();     return response.Content.ReadAsAsync<Identity>().Result; }   So you can see that it’s pretty straightforward to implement various authentication scenarios using WebAPI and my authentication library. Stay tuned for more client samples!

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• Wildcards!

  - by Tim Dexter

  Yes, its been a while, Im sorry, mumble, mumble ... no excuses. Well other than its been, as my son would say 'hecka busy.' On a brighter note I see Kan has been posting some cool stuff in my absence, long may he continue! I received a question today asking about using a wildcard in a template, something like: <?if:INVOICE = 'MLP*'?> where * is the wildcard Well that particular try does not work but you can do it without building your own wildcard function. XSL, the underpinning language of the RTF templates, has some useful string functions - you can find them listed here. I used the starts-with function to achieve a simple wildcard scenario but the contains can be used in conjunction with some of the others to build something more sophisticated. Assume I have a a list of friends and the amounts of money they owe me ... Im very generous and my interest rates a pretty competitive :0) <ROWSET> <ROW> <NAME>Andy</NAME> <AMT>100</AMT> </ROW> <ROW> <NAME>Andrew</NAME> <AMT>60</AMT> </ROW> <ROW> <NAME>Aaron</NAME> <AMT>50</AMT> </ROW> <ROW> <NAME>Alice</NAME> <AMT>40</AMT> </ROW> <ROW> <NAME>Bob</NAME> <AMT>10</AMT> </ROW> <ROW> <NAME>Bill</NAME> <AMT>100</AMT> </ROW> Now, listing my friends is easy enough <for-each:ROW> <NAME> <AMT> <end for-each> but lets say I just want to see all my friends beginning with 'A'. To do that I can use an XPATH expression to filter the data and tack it on to the for-each expression. This is more efficient that using an 'if' statement just inside the for-each. <?for-each:ROW[starts-with(NAME,'A')]?> will find me all the A's. The square braces denote the start of the XPATH expression. starts-with is the function Im calling and Im passing the value I want to check i.e. NAME and the string Im looking for. Just substitute in the characters you are looking for. You can of course use the function in a if statement too. <?if:starts-with(NAME,'A')?><?attribute@incontext:color;'red'?><?end if?> Notice I removed the square braces, this will highlight text red if the name begins with an 'A' You can even use the function to do conditional calculations: <?sum (AMT[starts-with(../NAME,'A')])?> Sum only the amounts where the name begins with an 'A' Notice the square braces are back, its a function we want to apply to the AMT field. Also notice that we need to use ../NAME. The AMT and NAME elements are at the same level in the tree, so when we are at the AMT level we need the ../ to go up a level to then come back down to test the NAME value. I have built out the above functions in a sample template here. Huge prizes for the first person to come up with a 'true' wildcard solution i.e. if NAME like '*im*exter* demand cash now!

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• MySql for Visual Studio 1.0.2 GA has been released

  - by fernando

  MySQL for Visual Studio is a new product including all of the Visual Studio integration previously available as part of Connector/Net.  The product is now released as GA and is appropriate for use in production environments.  It is compatible with MySQL Server versions 5.0-5.7 and Visual Studio versions 2008-2012.  It is now available as part of MySql Installer for Windows (http://dev.mysql.com/tech-resources/articles/mysql-installer-for-windows.html). The 1.0 version of MySQL for Visual Studio brings the following new features:   Workbench Launching.   MySql Utilities Launching.   Table Script Generation.   The functionality of the core libraries (ADO.NET, EF, ASP.NET providers is available as the separate download of Connector/NET 6.7). Features available from previous versions:        Server explorer connections     Design time support     Entity Framework designer (Database First & Model First)     Stored Routines Debugger     Intellisense     ASP.NET Website Configuration Tool Workbench Launching  ------------------------------------------- A context menu for connections in Server Explorer allows to launch Workbench (if Workbench is installed). MySql Utilities Launching  ------------------------------------------- A context menu for connections in Server Explorer allows to launch a prompt for MySql Utilities (if MySql Utilities is installed). Table Script Generation  ------------------------------------------- A context menu for tables is available in Server Explorer to generate the script for a table. The full list of bug fixes for "MySql for Visual Studio" 1.0 follows: 1.0.2 - Fix for Documentation not found (Oracle bug #6915712). - Fix for intellisense completion, now Views are displayed together with Tables calling intellisense (Oracle Bug #16881451). - Fix for parser syntax, now the parser supports the clause ALTER TABLE table_name RENAME {INDEX|KEY} old_index_name TO new_index_name introduced in MySql 5.7. (Oracle Bug #16881481) - Fix for Debugging a routine produces an error when binary log is enabled (Oracle bug #16941181). - Fix for WorkItem 552: MySql for Visual Studio Installer fails when installing against VS2008. - Fix for bug Vs plugin installer is not working (Oracle bug #16973339). - Fix for bug Release notes file has no notes about (Oracle bug #16973326). 1.0.1 - Fix for "README" file and "Release Notes" file referes to connector 6.6. - Fix for Parser fails to recognizes a complex view (Oracle bug #16815427). - Fix for Altering table's primary key in designer not working (Oracle bug #16866053). - Fix for Web configuration tool is not shown on mysql for visual studio (Oracle bug # 16902696). - Fix for Model first is not supported using mysql for visual studio (Oracle bug # 16902743). - Fix for Mysql for vs should not be installed with connector/net version < 6.7 (Oracle bug # 16902774). - Fix for Resolve assemblies dependencies between MySql.Data (Connector/Net version) and MySql.Data (WI # 460). - Fix for Showing an exception related to resources (Oracle bug #16903039). 1.0.0 - Added new option on Connection Node for Server Explorer Window in Visual Studio to give the user the option when WB is Installed to open the MySQL Utilities console window. - Added new option on Connection Node for Server Explorer Window in Visual Studio to give the user the option when WB is Installed to open the SQL Editor Window using the same connection. - Implemented a menu option to generate table script from server explorer context menu (Tracker task 433). - Fix for bug If using repair option, then vs2010 doesnt allow to connect to db (Oracle bug #16238242). - Fix for bug "Can't change the name for a view in view editor" (Oracle bug #13805346). - Fix for Debugger cannot debug stored procedures with a main begin labeled and declare statements included (Oracle bug #16002371). - Fix for bug If using repair option at Installer, then vs2010 doesnt allow to connect to db (Oracle bug #16238242). - Fix for "Cannot change the name for a Foreign Key in table designer" (Oracle bug #16238068). - Fix for error when trying to set primary key for a column with same name as mysql keyword (like INT) in table designer   (Oracle bug #16238102). - Fix for databases not displayed in connect dialog for mysql script when correcting credentials, after entering a bad password   (Oracle bug #13805337). - Fix for Debugger fails trying to debug a stored routine in a MySql server hosted in linux without lower_case_table_names option enabled   (MySql bug #69065, Oracle bug #16770384). - Fix for Debugger issue, Values through watch tab shouldn't allow to be modified (Oracle bug #14545448). - Fix for Visual Studio Mysql editor colors cannot be customized (Oracle bug #16453324, MySql bug #67994). The documentation is available as part of Connector/NET at http://dev.mysql.com/doc/refman/5.7/en/connector-net.html  Enjoy and thanks for the support!  --  Fernando Gonzalez Sanchez | Software Engineer |  Oracle MySQL Windows Experience Team, Connector/NET  Guadalajara | Jalisco | Mexico

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• How To Get Web Site Thumbnail Image In ASP.NET

  - by SAMIR BHOGAYTA

  Overview One very common requirement of many web applications is to display a thumbnail image of a web site. A typical example is to provide a link to a dynamic website displaying its current thumbnail image, or displaying images of websites with their links as a result of search (I love to see it on Google). Microsoft .NET Framework 2.0 makes it quite easier to do it in a ASP.NET application. Background In order to generate image of a web page, first we need to load the web page to get their html code, and then this html needs to be rendered in a web browser. After that, a screen shot can be taken easily. I think there is no easier way to do this. Before .NET framework 2.0 it was quite difficult to use a web browser in C# or VB.NET because we either have to use COM+ interoperability or third party controls which becomes headache later. WebBrowser control in .NET framework 2.0 In .NET framework 2.0 we have a new Windows Forms WebBrowser control which is a wrapper around old shwdoc.dll. All you really need to do is to drop a WebBrowser control from your Toolbox on your form in .NET framework 2.0. If you have not used WebBrowser control yet, it's quite easy to use and very consistent with other Windows Forms controls. Some important methods of WebBrowser control are. public bool GoBack(); public bool GoForward(); public void GoHome(); public void GoSearch(); public void Navigate(Uri url); public void DrawToBitmap(Bitmap bitmap, Rectangle targetBounds); These methods are self explanatory with their names like Navigate function which redirects browser to provided URL. It also has a number of useful overloads. The DrawToBitmap (inherited from Control) draws the current image of WebBrowser to the provided bitmap. Using WebBrowser control in ASP.NET 2.0 The Solution Let's start to implement the solution which we discussed above. First we will define a static method to get the web site thumbnail image. public static Bitmap GetWebSiteThumbnail(string Url, int BrowserWidth, int BrowserHeight, int ThumbnailWidth, int ThumbnailHeight) { WebsiteThumbnailImage thumbnailGenerator = new WebsiteThumbnailImage(Url, BrowserWidth, BrowserHeight, ThumbnailWidth, ThumbnailHeight); return thumbnailGenerator.GenerateWebSiteThumbnailImage(); } The WebsiteThumbnailImage class will have a public method named GenerateWebSiteThumbnailImage which will generate the website thumbnail image in a separate STA thread and wait for the thread to exit. In this case, I decided to Join method of Thread class to block the initial calling thread until the bitmap is actually available, and then return the generated web site thumbnail. public Bitmap GenerateWebSiteThumbnailImage() { Thread m_thread = new Thread(new ThreadStart(_GenerateWebSiteThumbnailImage)); m_thread.SetApartmentState(ApartmentState.STA); m_thread.Start(); m_thread.Join(); return m_Bitmap; } The _GenerateWebSiteThumbnailImage will create a WebBrowser control object and navigate to the provided Url. We also register for the DocumentCompleted event of the web browser control to take screen shot of the web page. To pass the flow to the other controls we need to perform a method call to Application.DoEvents(); and wait for the completion of the navigation until the browser state changes to Complete in a loop. private void _GenerateWebSiteThumbnailImage() { WebBrowser m_WebBrowser = new WebBrowser(); m_WebBrowser.ScrollBarsEnabled = false; m_WebBrowser.Navigate(m_Url); m_WebBrowser.DocumentCompleted += new WebBrowserDocument CompletedEventHandler(WebBrowser_DocumentCompleted); while (m_WebBrowser.ReadyState != WebBrowserReadyState.Complete) Application.DoEvents(); m_WebBrowser.Dispose(); } The DocumentCompleted event will be fired when the navigation is completed and the browser is ready for screen shot. We will get screen shot using DrawToBitmap method as described previously which will return the bitmap of the web browser. Then the thumbnail image is generated using GetThumbnailImage method of Bitmap class passing it the required thumbnail image width and height. private void WebBrowser_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e) { WebBrowser m_WebBrowser = (WebBrowser)sender; m_WebBrowser.ClientSize = new Size(this.m_BrowserWidth, this.m_BrowserHeight); m_WebBrowser.ScrollBarsEnabled = false; m_Bitmap = new Bitmap(m_WebBrowser.Bounds.Width, m_WebBrowser.Bounds.Height); m_WebBrowser.BringToFront(); m_WebBrowser.DrawToBitmap(m_Bitmap, m_WebBrowser.Bounds); m_Bitmap = (Bitmap)m_Bitmap.GetThumbnailImage(m_ThumbnailWidth, m_ThumbnailHeight, null, IntPtr.Zero); } One more example here : http://www.codeproject.com/KB/aspnet/Website_URL_Screenshot.aspx

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• SSIS: Building SQL databases on-the-fly using concatenated SQL scripts

  - by DrJohn

  Over the years I have developed many techniques which help automate the whole SQL Server build process. In my current process, where I need to build entire OLAP data marts on-the-fly, I make regular use of a simple but very effective mechanism to concatenate all the SQL Scripts together from my SSMS (SQL Server Management Studio) projects. This proves invaluable because in two clicks I can redeploy an entire SQL Server database with all tables, views, stored procedures etc. Indeed, I can also use the concatenated SQL scripts with SSIS to build SQL Server databases on-the-fly. You may be surprised to learn that I often redeploy the database several times per day, or even several times per hour, during the development process. This is because the deployment errors are logged and you can quickly see where SQL Scripts have object dependency errors. For example, after changing a table structure you may have forgotten to change any related views. The deployment log immediately points out all the objects which failed to build so you can fix and redeploy the database very quickly. The alternative approach (i.e. doing changes in the database directly using the SSMS UI) would require you to check all dependent objects before making changes. The chances are that you will miss something and wonder why your app returns the wrong data – a common problem caused by changing a table without re-creating dependent views. Using SQL Projects in SSMS A great many developers fail to make use of SQL Projects in SSMS (SQL Server Management Studio). To me they are invaluable way of organizing your SQL Scripts. The screenshot below shows a typical SSMS solution made up of several projects – one project for tables, another for views etc. The key point is that the projects naturally fall into the right order in file system because of the project name. The number in the folder or file name ensures that the projects the SQL scripts are concatenated together in the order that they need to be executed. Hence the script filenames start with 100, 110 etc. Concatenating SQL Scripts To concatenate the SQL Scripts together into one file, I use notepad.exe to create a simple batch file (see example screenshot) which uses the TYPE command to write the content of the SQL Script files into a combined file. As the SQL Scripts are in several folders, I simply use several TYPE command multiple times and append the output together. If you are unfamiliar with batch files, you may not know that the angled bracket (>) means write output of the program into a file. Two angled brackets (>>) means append output of this program into a file. So the command-line DIR > filelist.txt would write the content of the DIR command into a file called filelist.txt. In the example shown above, the concatenated file is called SB_DDS.sql If, like me you place the concatenated file under source code control, then the source code control system will change the file's attribute to "read-only" which in turn would cause the TYPE command to fail. The ATTRIB command can be used to remove the read-only flag. Using SQLCmd to execute the concatenated file Now that the SQL Scripts are all in one big file, we can execute the script against a database using SQLCmd using another batch file as shown below: SQLCmd has numerous options, but the script shown above simply executes the SS_DDS.sql file against the SB_DDS_DB database on the local machine and logs the errors to a file called SB_DDS.log. So after executing the batch file you can simply check the error log to see if your database built without a hitch. If you have errors, then simply fix the source files, re-create the concatenated file and re-run the SQLCmd to rebuild the database. This two click operation allows you to quickly identify and fix errors in your entire database definition.Using SSIS to execute the concatenated file To execute the concatenated SQL script using SSIS, you simply drop an Execute SQL task into your package and set the database connection as normal and then select File Connection as the SQLSourceType (as shown below). Create a file connection to your concatenated SQL script and you are ready to go.   Tips and TricksAdd a new-line at end of every fileThe most common problem encountered with this approach is that the GO statement on the last line of one file is placed on the same line as the comment at the top of the next file by the TYPE command. The easy fix to this is to ensure all your files have a new-line at the end.Remove all USE database statementsThe SQLCmd identifies which database the script should be run against.  So you should remove all USE database commands from your scripts - otherwise you may get unintentional side effects!!Do the Create Database separatelyIf you are using SSIS to create the database as well as create the objects and populate the database, then invoke the CREATE DATABASE command against the master database using a separate package before calling the package that executes the concatenated SQL script.    

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• Clean way to use mutable implementation of Immutable interfaces for encapsulation

  - by dsollen

  My code is working on some compost relationship which creates a tree structure, class A has many children of type B, which has many children of type C etc. The lowest level class, call it bar, also points to a connected bar class. This effectively makes nearly every object in my domain inter-connected. Immutable objects would be problematic due to the expense of rebuilding almost all of my domain to make a single change to one class. I chose to go with an interface approach. Every object has an Immutable interface which only publishes the getter methods. I have controller objects which constructs the domain objects and thus has reference to the full objects, thus capable of calling the setter methods; but only ever publishes the immutable interface. Any change requested will go through the controller. So something like this: public interface ImmutableFoo{ public Bar getBar(); public Location getLocation(); } public class Foo implements ImmutableFoo{ private Bar bar; private Location location; @Override public Bar getBar(){ return Bar; } public void setBar(Bar bar){ this.bar=bar; } @Override public Location getLocation(){ return Location; } } public class Controller{ Private Map<Location, Foo> fooMap; public ImmutableFoo addBar(Bar bar){ Foo foo=fooMap.get(bar.getLocation()); if(foo!=null) foo.addBar(bar); return foo; } } I felt the basic approach seems sensible, however, when I speak to others they always seem to have trouble envisioning what I'm describing, which leaves me concerned that I may have a larger design issue then I'm aware of. Is it problematic to have domain objects so tightly coupled, or to use the quasi-mutable approach to modifying them? Assuming that the design approach itself isn't inherently flawed the particular discussion which left me wondering about my approach had to do with the presence of business logic in the domain objects. Currently I have my setter methods in the mutable objects do error checking and all other logic required to verify and make a change to the object. It was suggested that this should be pulled out into a service class, which applies all the business logic, to simplify my domain objects. I understand the advantage in mocking/testing and general separation of logic into two classes. However, with a service method/object It seems I loose some of the advantage of polymorphism, I can't override a base class to add in new error checking or business logic. It seems, if my polymorphic classes were complicated enough, I would end up with a service method that has to check a dozen flags to decide what error checking and business logic applies. So, for example, if I wanted to have a childFoo which also had a size field which should be compared to bar before adding par my current approach would look something like this. public class Foo implements ImmutableFoo{ public void addBar(Bar bar){ if(!getLocation().equals(bar.getLocation()) throw new LocationException(); this.bar=bar; } } public interface ImmutableChildFoo extends ImmutableFoo{ public int getSize(); } public ChildFoo extends Foo implements ImmutableChildFoo{ private int size; @Override public int getSize(){ return size; } @Override public void addBar(Bar bar){ if(getSize()<bar.getSize()){ throw new LocationException(); super.addBar(bar); } My colleague was suggesting instead having a service object that looks something like this (over simplified, the 'service' object would likely be more complex). public interface ImmutableFoo{ ///original interface, presumably used in other methods public Location getLocation(); public boolean isChildFoo(); } public interface ImmutableSizedFoo implements ImmutableFoo{ public int getSize(); } public class Foo implements ImmutableSizedFoo{ public Bar bar; @Override public void addBar(Bar bar){ this.bar=bar; } @Override public int getSize(){ //default size if no size is known return 0; } @Override public boolean isChildFoo return false; } } public ChildFoo extends Foo{ private int size; @Override public int getSize(){ return size; } @Override public boolean isChildFoo(); return true; } } public class Controller{ Private Map<Location, Foo> fooMap; public ImmutableSizedFoo addBar(Bar bar){ Foo foo=fooMap.get(bar.getLocation()); service.addBarToFoo(foo, bar); returned foo; } public class Service{ public static void addBarToFoo(Foo foo, Bar bar){ if(foo==null) return; if(!foo.getLocation().equals(bar.getLocation())) throw new LocationException(); if(foo.isChildFoo() && foo.getSize()<bar.getSize()) throw new LocationException(); foo.setBar(bar); } } } Is the recommended approach of using services and inversion of control inherently superior, or superior in certain cases, to overriding methods directly? If so is there a good way to go with the service approach while not loosing the power of polymorphism to override some of the behavior?

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• How to make creating viewmodels at runtime less painful

  - by Mr Happy

  I apologize for the long question, it reads a bit as a rant, but I promise it's not! I've summarized my question(s) below In the MVC world, things are straightforward. The Model has state, the View shows the Model, and the Controller does stuff to/with the Model (basically), a controller has no state. To do stuff the Controller has some dependencies on web services, repository, the lot. When you instantiate a controller you care about supplying those dependencies, nothing else. When you execute an action (method on Controller), you use those dependencies to retrieve or update the Model or calling some other domain service. If there's any context, say like some user wants to see the details of a particular item, you pass the Id of that item as parameter to the Action. Nowhere in the Controller is there any reference to any state. So far so good. Enter MVVM. I love WPF, I love data binding. I love frameworks that make data binding to ViewModels even easier (using Caliburn Micro a.t.m.). I feel things are less straightforward in this world though. Let's do the exercise again: the Model has state, the View shows the ViewModel, and the ViewModel does stuff to/with the Model (basically), a ViewModel does have state! (to clarify; maybe it delegates all the properties to one or more Models, but that means it must have a reference to the model one way or another, which is state in itself) To do stuff the ViewModel has some dependencies on web services, repository, the lot. When you instantiate a ViewModel you care about supplying those dependencies, but also the state. And this, ladies and gentlemen, annoys me to no end. Whenever you need to instantiate a ProductDetailsViewModel from the ProductSearchViewModel (from which you called the ProductSearchWebService which in turn returned IEnumerable<ProductDTO>, everybody still with me?), you can do one of these things: call new ProductDetailsViewModel(productDTO, _shoppingCartWebService /* dependcy */);, this is bad, imagine 3 more dependencies, this means the ProductSearchViewModel needs to take on those dependencies as well. Also changing the constructor is painful. call _myInjectedProductDetailsViewModelFactory.Create().Initialize(productDTO);, the factory is just a Func, they are easily generated by most IoC frameworks. I think this is bad because Init methods are a leaky abstraction. You also can't use the readonly keyword for fields that are set in the Init method. I'm sure there are a few more reasons. call _myInjectedProductDetailsViewModelAbstractFactory.Create(productDTO); So... this is the pattern (abstract factory) that is usually recommended for this type of problem. I though it was genius since it satisfies my craving for static typing, until I actually started using it. The amount of boilerplate code is I think too much (you know, apart from the ridiculous variable names I get use). For each ViewModel that needs runtime parameters you'll get two extra files (factory interface and implementation), and you need to type the non-runtime dependencies like 4 extra times. And each time the dependencies change, you get to change it in the factory as well. It feels like I don't even use a DI container anymore. (I think Castle Windsor has some kind of solution for this [with it's own drawbacks, correct me if I'm wrong]). do something with anonymous types or dictionary. I like my static typing. So, yeah. Mixing state and behavior in this way creates a problem which don't exist at all in MVC. And I feel like there currently isn't a really adequate solution for this problem. Now I'd like to observe some things: People actually use MVVM. So they either don't care about all of the above, or they have some brilliant other solution. I haven't found an in-depth example of MVVM with WPF. For example, the NDDD-sample project immensely helped me understand some DDD concepts. I'd really like it if someone could point me in the direction of something similar for MVVM/WPF. Maybe I'm doing MVVM all wrong and I should turn my design upside down. Maybe I shouldn't have this problem at all. Well I know other people have asked the same question so I think I'm not the only one. To summarize Am I correct to conclude that having the ViewModel being an integration point for both state and behavior is the reason for some difficulties with the MVVM pattern as a whole? Is using the abstract factory pattern the only/best way to instantiate a ViewModel in a statically typed way? Is there something like an in depth reference implementation available? Is having a lot of ViewModels with both state/behavior a design smell?

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• Extending Database-as-a-Service to Provision Databases with Application Data

  - by Nilesh A

  Oracle Enterprise Manager 12c Database as a Service (DBaaS) empowers Self Service/SSA Users to rapidly spawn databases on demand in cloud. The configuration and structure of provisioned databases depends on respective service template selected by Self Service user while requesting for database. In EM12c, the DBaaS Self Service/SSA Administrator has the option of hosting various service templates in service catalog and based on underlying DBCA templates.Many times provisioned databases require production scale data either for UAT, testing or development purpose and managing DBCA templates with data can be unwieldy. So, we need to populate the database using post deployment script option and without any additional work for the SSA Users. The SSA Administrator can automate this task in few easy steps. For details on how to setup DBaaS Self Service Portal refer to the DBaaS CookbookIn this article, I will list steps required to enable EM 12c DBaaS to provision databases with application data in two distinct ways using: 1) Data pump 2) Transportable tablespaces (TTS). The steps listed below are just examples of how to extend EM 12c DBaaS and you can even have your own method plugged in part of post deployment script option. Using Data Pump to populate databases These are the steps to be followed to implement extending DBaaS using Data Pump methodolgy: Production DBA should run data pump export on the production database and make the dump file available to all the servers participating in the database zone [sample shown in Fig.1] -- Full exportexpdp FULL=y DUMPFILE=data_pump_dir:dpfull1%U.dmp, data_pump_dir:dpfull2%U.dmp PARALLEL=4 LOGFILE=data_pump_dir:dpexpfull.log JOB_NAME=dpexpfull Figure-1:  Full export of database using data pump Create a post deployment SQL script [sample shown in Fig. 2] and this script can either be uploaded into the software library by SSA Administrator or made available on a shared location accessible from servers where databases are likely to be provisioned Normal 0 -- Full importdeclare    h1   NUMBER;begin-- Creating the directory object where source database dump is backed up.    execute immediate 'create directory DEST_LOC as''/scratch/nagrawal/OracleHomes/oradata/INITCHNG/datafile''';-- Running import    h1 := dbms_datapump.open (operation => 'IMPORT', job_mode => 'FULL', job_name => 'DB_IMPORT10');    dbms_datapump.set_parallel(handle => h1, degree => 1);    dbms_datapump.add_file(handle => h1, filename => 'IMP_GRIDDB_FULL.LOG', directory => 'DATA_PUMP_DIR', filetype => 3);    dbms_datapump.add_file(handle => h1, filename => 'EXP_GRIDDB_FULL_%U.DMP', directory => 'DEST_LOC', filetype => 1);    dbms_datapump.start_job(handle => h1);    dbms_datapump.detach(handle => h1);end;/ Figure-2: Importing using data pump pl/sql procedures Using DBCA, create a template for the production database – include all the init.ora parameters, tablespaces, datafiles & their sizes SSA Administrator should customize “Create Database Deployment Procedure” and provide DBCA template created in the previous step. In “Additional Configuration Options” step of Customize “Create Database Deployment Procedure” flow, provide the name of the SQL script in the Custom Script section and lock the input (shown in Fig. 3). Continue saving the deployment procedure. Figure-3: Using Custom script option for calling Import SQL Now, an SSA user can login to Self Service Portal and use the flow to provision a database that will also  populate the data using the post deployment step. Using Transportable tablespaces to populate databases Copy of all user/application tablespaces will enable this method of populating databases. These are the required steps to extend DBaaS using transportable tablespaces: Production DBA needs to create a backup of tablespaces. Datafiles may need conversion [such as from Big Endian to Little Endian or vice versa] based on the platform of production and destination where DBaaS created the test database. Here is sample backup script shows how to find out if any conversion is required, describes the steps required to convert datafiles and backup tablespace. SSA Administrator should copy the database (tablespaces) backup datafiles and export dumps to the backup location accessible from the hosts participating in the database zone(s). Create a post deployment SQL script and this script can either be uploaded into the software library by SSA Administrator or made available on a shared location accessible from servers where databases are likely to be provisioned. Here is sample post deployment SQL script using transportable tablespaces. Using DBCA, create a template for the production database – all the init.ora parameters should be included. NOTE: DO NOT choose to bring tablespace data into this template as they will be created SSA Administrator should customize “Create Database Deployment Procedure” and provide DBCA template created in the previous step. In the “Additional Configuration Options” step of the flow, provide the name of the SQL script in the Custom Script section and lock the input. Continue saving the deployment procedure. Now, an SSA user can login to Self Service Portal and use the flow to provision a database that will also populate the data using the post deployment step. More Information: Database-as-a-Service on Exadata Cloud Podcast on Database as a Service using Oracle Enterprise Manager 12c Oracle Enterprise Manager 12c Installation and Administration guide, Cloud Administration guide DBaaS Cookbook Screenwatch: Private Database Cloud: Set Up the Cloud Self-Service Portal Screenwatch: Private Database Cloud: Use the Cloud Self-Service Portal Stay Connected: Twitter |  Face book |  You Tube |  Linked in |  Newsletter

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• MySQL Connector/Net 6.6.3 Beta 2 has been released

  - by fernando

  MySQL Connector/Net 6.6.3, a new version of the all-managed .NET driver for MySQL has been released.  This is the second of two beta releases intended to introduce users to the new features in the release. This release is feature complete it should be stable enough for users to understand the new features and how we expect them to work.  As is the case with all non-GA releases, it should not be used in any production environment.  It is appropriate for use with MySQL server versions 5.0-5.6. It is now available in source and binary form from http://dev.mysql.com/downloads/connector/net/#downloads and mirror sites (note that not all mirror sites may be up to date at this point-if you can't find this version on some mirror, please try again later or choose another download site.) The 6.6 version of MySQL Connector/Net brings the following new features:   * Stored routine debugging   * Entity Framework 4.3 Code First support   * Pluggable authentication (now third parties can plug new authentications mechanisms into the driver).   * Full Visual Studio 2012 support: everything from Server Explorer to Intellisense&   the Stored Routine debugger. Stored Procedure Debugging ------------------------------------------- We are very excited to introduce stored procedure debugging into our Visual Studio integration.  It works in a very intuitive manner by simply clicking 'Debug Routine' from Server Explorer. You can debug stored routines, functions&   triggers. These release contains fixes specific of the debugger as well as other fixes specific of other areas of Connector/NET:   * Added feature to define initial values for InOut stored procedure arguments.   * Debugger: Fixed Visual Studio locked connection after debugging a routine.   * Fix for bug Cannot Create an Entity with a Key of Type String (MySQL bug #65289, Oracle bug #14540202).   * Fix for bug "CacheServerProperties can cause 'Packet too large' error". MySQL Bug #66578 Orabug #14593547.   * Fix for handling unnamed parameter in MySQLCommand. This fix allows the mysqlcommand to handle parameters without requiring naming (e.g. INSERT INTO Test (id,name) VALUES (?, ?) ) (MySQL Bug #66060, Oracle bug #14499549).   * Fixed end of line issue when debugging a routine.   * Added validation to avoid overwriting a routine backup file when it hasn't changed.   * Fixed inheritance on Entity Framework Code First scenarios. (MySql bug #63920 and Oracle bug #13582335).   * Fixed "Trying to customize column precision in Code First does not work" (MySql bug #65001, Oracle bug #14469048).   * Fixed bug ASP.NET Membership database fails on MySql database UTF32 (MySQL bug #65144, Oracle bug #14495292).   * Fix for MySqlCommand.LastInsertedId holding only 32 bit values (MySql bug #65452, Oracle bug #14171960).   * Fixed "Decimal type should have digits at right of decimal point", now default is 2, and user's changes in     EDM designer are recognized (MySql bug #65127, Oracle bug #14474342).   * Fix for NullReferenceException when saving an uninitialized row in Entity Framework (MySql bug #66066, Oracle bug #14479715).   * Fix for error when calling RoleProvider.RemoveUserFromRole(): causes an exception due to a wrong table being used (MySql bug #65805, Oracle bug #14405338).   * Fix for "Memory Leak on MySql.Data.MySqlClient.MySqlCommand", too many MemoryStream's instances created (MySql bug #65696, Oracle bug #14468204).   * Added ANTLR attribution notice (Oracle bug #14379162).   * Fix for debugger failing when having a routine with an if-elseif-else.   * Also the programming interface for authentication plugins has been redefined. Some limitations remains, due to the current debugger architecture:   * Some MySQL functions cannot be debugged currently (get_lock, release_lock, begin, commit, rollback, set transaction level)..   * Only one debug session may be active on a given server. The Debugger is feature complete at this point. We look forward to your feedback. Documentation ------------------------------------- You can view current Connector/Net documentation at http://dev.mysql.com/doc/refman/5.5/en/connector-net.html You can find our team blog at http://blogs.oracle.com/MySQLOnWindows. You can also post questions on our forums at http://forums.mysql.com/. Enjoy and thanks for the support!

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• Drawing on a webpage – HTML5 - IE9

  - by nmarun

  So I upgraded to IE9 and continued exploring HTML5. Now there’s this ‘thing’ called Canvas in HTML5 with which you can do some cool stuff. Alright what IS this Canvas thing anyways? The Web Hypertext Application Technology Working Group says this: “The canvas element provides scripts with a resolution-dependent bitmap canvas, which can be used for rendering graphs, game graphics, or other visual images on the fly.” The Canvas element has two only attributes – width and height and when not specified they take up the default values of 300 and 150 respectively. Below is what my HTML file looks like: 1: <!DOCTYPE html> 2: <html lang="en-US"> 3: <head> 4: <script type="text/javascript" src="CustomScript.js"></script> 5: <script src="jquery-1.4.4.js" type="text/javascript"></script 6:  7: <title>Draw on a webpage</title> 8: </head> 9: <body> 10: <canvas id="canvas" width="500" height="500"></canvas> 11: <br /> 12: <input type="submit" id="submit" value="Clear" /> 13: <h4 id="currentPosition"> 14: 0, 0 15: </h4> 16: <div id="mousedownCoords"></div> 17: </body> 18: </html> In case you’re wondering, this is not a MVC or any kind of web application. This is plain ol’ HTML even though I’m writing all this in VS 2010. You see this is a very simple, ‘gimmicks-free’ html page. I have declared a Canvas element on line 10 and a button on line 11 to clear the drawing board. I’m using jQuery / JavaScript show the current position of the mouse on the screen. This will get updated in the ‘currentPosition’ <h4> tag and I’m using the ‘mousedownCoords’ to write all the places where the mouse was clicked. This is what my page renders as: The rectangle with a background is our canvas. The coloring is due to some javascript (which we’ll see in a moment). Now let’s get to our CustomScript.js file. 1: jQuery(document).ready(function () { 2: var isFirstClick = true; 3: var canvas = document.getElementById("canvas"); 4: // getContext: Returns an object that exposes an API for drawing on the canvas 5: var canvasContext = canvas.getContext("2d"); 6: fillBackground(); 7:  8: $("#submit").click(function () { 9: clearCanvas(); 10: fillBackground(); 11: }); 12:  13: $(document).mousemove(function (e) { 14: $('#currentPosition').html(e.pageX + ', ' + e.pageY); 15: }); 16: $(document).mouseup(function (e) { 17: // on the first click 18: // set the moveTo 19: if (isFirstClick == true) { 20: canvasContext.beginPath(); 21: canvasContext.moveTo(e.pageX - 7, e.pageY - 7); 22: isFirstClick = false; 23: } 24: else { 25: // on subsequent clicks, draw a line 26: canvasContext.lineTo(e.pageX - 7, e.pageY - 7); 27: canvasContext.stroke(); 28: } 29:  30: $('#mousedownCoords').text($('#mousedownCoords').text() + '(' + e.pageX + ',' + e.pageY + ')'); 31: }); 32:  33: function fillBackground() { 34: canvasContext.fillStyle = '#a1b1c3'; 35: canvasContext.fillRect(0, 0, 500, 500); 36: canvasContext.fill(); 37: } 38:  39: function clearCanvas() { 40: // wipe-out the canvas 41: canvas.width = canvas.width; 42: // set the isFirstClick to true 43: // so the next shape can begin 44: isFirstClick = true; 45: // clear the text 46: $('#mousedownCoords').text(''); 47: } 48: })   The script only looks long and complicated, but is not. I’ll go over the main steps. Get a ‘hold’ of your canvas object and retrieve the ‘2d’ context out of it. On mousemove event, write the current x and y coordinates to the ‘currentPosition’ element. On mouseup event, check if this is the first time the user has clicked on the canvas. The coloring of the canvas is done in the fillBackground() function. We first need to start a new path. This is done by calling the beginPath() function on our context. The moveTo() function sets the starting point of our path. The lineTo() function sets the end point of the line to be drawn. The stroke() function is the one that actually draws the line on our canvas. So if you want to play with the demo, here’s how you do it. First click on the canvas (nothing visible happens on the canvas). The second click draws a line from the first click to the current coordinates and so on and so forth. Click on the ‘Clear’ button, to reset the canvas and to give your creativity a clean slate. Here’s a sample output: Happy drawing! Verdict: HTML5 and IE9 – I think we’re on to something big and great here!

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• Subterranean IL: Generics and array covariance

  - by Simon Cooper

  Arrays in .NET are curious beasts. They are the only built-in collection types in the CLR, and SZ-arrays (single dimension, zero-indexed) have their own commands and IL syntax. One of their stranger properties is they have a kind of built-in covariance long before generic variance was added in .NET 4. However, this causes a subtle but important problem with generics. First of all, we need to briefly recap on array covariance. SZ-array covariance To demonstrate, I'll tweak the classes I introduced in my previous posts: public class IncrementableClass { public int Value; public virtual void Increment(int incrementBy) { Value += incrementBy; } } public class IncrementableClassx2 : IncrementableClass { public override void Increment(int incrementBy) { base.Increment(incrementBy); base.Increment(incrementBy); } } In the CLR, SZ-arrays of reference types are implicitly convertible to arrays of the element's supertypes, all the way up to object (note that this does not apply to value types). That is, an instance of IncrementableClassx2[] can be used wherever a IncrementableClass[] or object[] is required. When an SZ-array could be used in this fashion, a run-time type check is performed when you try to insert an object into the array to make sure you're not trying to insert an instance of IncrementableClass into an IncrementableClassx2[]. This check means that the following code will compile fine but will fail at run-time: IncrementableClass[] array = new IncrementableClassx2[1]; array[0] = new IncrementableClass(); // throws ArrayTypeMismatchException These checks are enforced by the various stelem* and ldelem* il instructions in such a way as to ensure you can't insert a IncrementableClass into a IncrementableClassx2[]. For the rest of this post, however, I'm going to concentrate on the ldelema instruction. ldelema This instruction pops the array index (int32) and array reference (O) off the stack, and pushes a pointer (&) to the corresponding array element. However, unlike the ldelem instruction, the instruction's type argument must match the run-time array type exactly. This is because, once you've got a managed pointer, you can use that pointer to both load and store values in that array element using the ldind* and stind* (load/store indirect) instructions. As the same pointer can be used for both input and output to the array, the type argument to ldelema must be invariant. At the time, this was a perfectly reasonable restriction, and maintained array type-safety within managed code. However, along came generics, and with it the constrained callvirt instruction. So, what happens when we combine array covariance and constrained callvirt? .method public static void CallIncrementArrayValue() { // IncrementableClassx2[] arr = new IncrementableClassx2[1] ldc.i4.1 newarr IncrementableClassx2 // arr[0] = new IncrementableClassx2(); dup newobj instance void IncrementableClassx2::.ctor() ldc.i4.0 stelem.ref // IncrementArrayValue<IncrementableClass>(arr, 0) // here, we're treating an IncrementableClassx2[] as IncrementableClass[] dup ldc.i4.0 call void IncrementArrayValue<class IncrementableClass>(!!0[],int32) // ... ret } .method public static void IncrementArrayValue<(IncrementableClass) T>( !!T[] arr, int32 index) { // arr[index].Increment(1) ldarg.0 ldarg.1 ldelema !!T ldc.i4.1 constrained. !!T callvirt instance void IIncrementable::Increment(int32) ret } And the result: Unhandled Exception: System.ArrayTypeMismatchException: Attempted to access an element as a type incompatible with the array. at IncrementArrayValue[T](T[] arr, Int32 index) at CallIncrementArrayValue() Hmm. We're instantiating the generic method as IncrementArrayValue<IncrementableClass>, but passing in an IncrementableClassx2[], hence the ldelema instruction is failing as it's expecting an IncrementableClass[]. On features and feature conflicts What we've got here is a conflict between existing behaviour (ldelema ensuring type safety on covariant arrays) and new behaviour (managed pointers to object references used for every constrained callvirt on generic type instances). And, although this is an edge case, there is no general workaround. The generic method could be hidden behind several layers of assemblies, wrappers and interfaces that make it a requirement to use array covariance when calling the generic method. Furthermore, this will only fail at runtime, whereas compile-time safety is what generics were designed for! The solution is the readonly. prefix instruction. This modifies the ldelema instruction to ignore the exact type check for arrays of reference types, and so it lets us take the address of array elements using a covariant type to the actual run-time type of the array: .method public static void IncrementArrayValue<(IncrementableClass) T>( !!T[] arr, int32 index) { // arr[index].Increment(1) ldarg.0 ldarg.1 readonly. ldelema !!T ldc.i4.1 constrained. !!T callvirt instance void IIncrementable::Increment(int32) ret } But what about type safety? In return for ignoring the type check, the resulting controlled mutability pointer can only be used in the following situations: As the object parameter to ldfld, ldflda, stfld, call and constrained callvirt instructions As the pointer parameter to ldobj or ldind* As the source parameter to cpobj In other words, the only operations allowed are those that read from the pointer; stind* and similar that alter the pointer itself are banned. This ensures that the array element we're pointing to won't be changed to anything untoward, and so type safety within the array is maintained. This is a typical example of the maxim that whenever you add a feature to a program, you have to consider how that feature interacts with every single one of the existing features. Although an edge case, the readonly. prefix instruction ensures that generics and array covariance work together and that compile-time type safety is maintained. Tune in next time for a look at the .ctor generic type constraint, and what it means.

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• Displaying text letter by letter

  - by Evi

  I am planing to Write a Text adventure and I don't know how to make the text draw letter by letter in any other way than changing the variable from h to he to hel to hell to hello That would be a terrible amount of work since there are tons of dialogue. Here is the source code so far { /// <summary> /// This is the main type for your game /// </summary> public class Game1 : Microsoft.Xna.Framework.Game { GraphicsDeviceManager graphics; SpriteBatch spriteBatch; Texture2D sampleBG; Texture2D TextBG; SpriteFont defaultfont; KeyboardState keyboardstate; public bool spacepress = false; public bool mspress = false; public int textheight = 425; public int rowspace = 40; public string namebox = "(null)"; public string Row1 = "(null)"; public string Row2 = "(null)"; public string Row3 = "(null)"; public string Row4 = "(null)"; public int Dialogue = 0; public Game1() { graphics = new GraphicsDeviceManager(this); Content.RootDirectory = "Content"; graphics.PreferredBackBufferHeight = 600; graphics.PreferredBackBufferWidth = 800; IsMouseVisible = true; } /// <summary> /// Allows the game to perform any initialization it needs to before starting to run. /// This is where it can query for any required services and load any non-graphic /// related content. Calling base.Initialize will enumerate through any components /// and initialize them as well. /// </summary> protected override void Initialize() { // TODO: Add your initialization logic here base.Initialize(); } /// <summary> /// LoadContent will be called once per game and is the place to load /// all of your content. /// </summary> protected override void LoadContent() { // Create a new SpriteBatch, which can be used to draw textures. spriteBatch = new SpriteBatch(GraphicsDevice); // TODO: use this.Content to load your game content here sampleBG = Content.Load <Texture2D>("SampleBG"); defaultfont = Content.Load<SpriteFont>("SpriteFont1"); TextBG = Content.Load<Texture2D>("textbg"); } /// <summary> /// UnloadContent will be called once per game and is the place to unload /// all content. /// </summary> protected override void UnloadContent() { // TODO: Unload any non ContentManager content here } /// <summary> /// Allows the game to run logic such as updating the world, /// checking for collisions, gathering input, and playing audio. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Update(GameTime gameTime) { KeyboardState keyboardstate = Keyboard.GetState(); MouseState mousestate = Mouse.GetState(); // Changes Dialgue by pressing Left Mouse Button or Space #region Dialogue changer if (mousestate.LeftButton == ButtonState.Pressed && mspress == false) { mspress = true; Dialogue = Dialogue + 1; } if (mousestate.LeftButton == ButtonState.Released && mspress == true) { mspress = false; } if (keyboardstate.IsKeyDown(Keys.Space) && spacepress == false) { spacepress = true; Dialogue = Dialogue + 1; } if (keyboardstate.IsKeyUp(Keys.Space) && spacepress == true) { spacepress = false; } #endregion // ------------------------------------------------------ // Dialgue Content #region Dialgue if (Dialogue == 1) { Row1 = "Input Text 1 Here."; Row2 = "Input Text 2 Here."; Row3 = "Input Text 3 Here."; Row4 = "Input Text 4 Here."; } if (Dialogue == 2) { Row1 = "Text 1"; Row2 = "Text 2"; Row3 = "Text 3"; Row4 = "Text 4"; } #endregion // ------------------------------------------------------ base.Update(gameTime); } /// <summary> /// This is called when the game should draw itself. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Draw(GameTime gameTime) { GraphicsDevice.Clear(Color.CornflowerBlue); // TODO: Add your drawing code here spriteBatch.Begin(); spriteBatch.Draw(sampleBG, new Rectangle(0, 0, 800, 600), Color.White); spriteBatch.Draw(TextBG, new Rectangle(0, 400, 800, 200), Color.White); spriteBatch.DrawString(defaultfont, Row1, new Vector2(10, (textheight + (rowspace * 0))), Color.Black); spriteBatch.DrawString(defaultfont, Row2, new Vector2(10, (textheight + (rowspace * 1))), Color.Black); spriteBatch.DrawString(defaultfont, Row3, new Vector2(10, (textheight + (rowspace * 2))), Color.Black); spriteBatch.DrawString(defaultfont, Row4, new Vector2(10, (textheight + (rowspace * 3))), Color.Black); spriteBatch.End(); base.Draw(gameTime); } } }

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• How to draw textures on a model

  - by marc wellman

  The following code is a complete XNA 3.1 program almost unaltered to that code skeleton Visual Studio is creating when creating a new project. The only things I have changed are imported a .x model to the content folder of the VS solution. (the model is a simple square with a texture spanning over it - made in Google Sketchup and exported with several .x exporters) in the Load() method I am loading the .x model into the game. The Draw() method uses a BasicEffect to render the model. Except these three things I haven't added any code. Why does the model does not show the texture ? What can I do to make the texture visible ? This is the texture file (a standard SketchUp texture from the palette): And this is what my program looks like - as you can see: No texture! Find below the complete source code of the program AND the complete .x file: namespace WindowsGame1 { /// <summary> /// This is the main type for your game /// </summary> public class Game1 : Microsoft.Xna.Framework.Game { GraphicsDeviceManager graphics; SpriteBatch spriteBatch; public Game1() { graphics = new GraphicsDeviceManager(this); Content.RootDirectory = "Content"; } /// <summary> /// Allows the game to perform any initialization it needs to before starting to run. /// This is where it can query for any required services and load any non-graphic /// related content. Calling base.Initialize will enumerate through any components /// and initialize them as well. /// </summary> protected override void Initialize() { // TODO: Add your initialization logic here base.Initialize(); } Model newModel; /// <summary> /// LoadContent will be called once per game and is the place to load /// all of your content. /// </summary> protected override void LoadContent() { // Create a new SpriteBatch, which can be used to draw textures. spriteBatch = new SpriteBatch(GraphicsDevice); // TODO: usse this.Content to load your game content here newModel = Content.Load<Model>(@"aau3d"); foreach (ModelMesh mesh in newModel.Meshes) { foreach (ModelMeshPart meshPart in mesh.MeshParts) { meshPart.Effect = new BasicEffect(this.GraphicsDevice, null); } } } /// <summary> /// UnloadContent will be called once per game and is the place to unload /// all content. /// </summary> protected override void UnloadContent() { // TODO: Unload any non ContentManager content here } /// <summary> /// Allows the game to run logic such as updating the world, /// checking for collisions, gathering input, and playing audio. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Update(GameTime gameTime) { // Allows the game to exit if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed) this.Exit(); // TODO: Add your update logic here base.Update(gameTime); } /// <summary> /// This is called when the game should draw itself. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Draw(GameTime gameTime) { if (newModel != null) { GraphicsDevice.Clear(Color.CornflowerBlue); Matrix[] transforms = new Matrix[newModel.Bones.Count]; newModel.CopyAbsoluteBoneTransformsTo(transforms); foreach (ModelMesh mesh in newModel.Meshes) { foreach (BasicEffect effect in mesh.Effects) { effect.EnableDefaultLighting(); effect.TextureEnabled = true; effect.World = transforms[mesh.ParentBone.Index] * Matrix.CreateRotationY(0) * Matrix.CreateTranslation(new Vector3(0, 0, 0)); effect.View = Matrix.CreateLookAt(new Vector3(200, 1000, 200), Vector3.Zero, Vector3.Up); effect.Projection = Matrix.CreatePerspectiveFieldOfView(MathHelper.ToRadians(45.0f), 0.75f, 1.0f, 10000.0f); } mesh.Draw(); } } base.Draw(gameTime); } } } This is the model I am using (.x): xof 0303txt 0032 // SketchUp 6 -> DirectX (c)2008 edecadoudal, supports: faces, normals and textures Material Default_Material{ 1.0;1.0;1.0;1.0;; 3.2; 0.000000;0.000000;0.000000;; 0.000000;0.000000;0.000000;; } Material _Groundcover_RiverRock_4inch_{ 0.568627450980392;0.494117647058824;0.427450980392157;1.0;; 3.2; 0.000000;0.000000;0.000000;; 0.000000;0.000000;0.000000;; TextureFilename { "aau3d.xGroundcover_RiverRock_4inch.jpg"; } } Mesh mesh_0{ 4; -81.6535;0.0000;74.8031;, -0.0000;0.0000;0.0000;, -81.6535;0.0000;0.0000;, -0.0000;0.0000;74.8031;; 2; 3;0,1,2, 3;1,0,3;; MeshMaterialList { 2; 2; 1, 1; { Default_Material } { _Groundcover_RiverRock_4inch_ } } MeshTextureCoords { 4; -2.1168,-3.4022; 1.0000,-0.0000; 1.0000,-3.4022; -2.1168,-0.0000;; } MeshNormals { 4; 0.0000;1.0000;-0.0000; 0.0000;1.0000;-0.0000; 0.0000;1.0000;-0.0000; 0.0000;1.0000;-0.0000;; 2; 3;0,1,2; 3;1,0,3;; } }

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• Poor Customer Service Example

  - by MightyZot

  Lately I have been frustrated by examples of poor customer service. At least one is worth writing about because I don’t think companies realize the effects of their service policies on loyal customers. Bad Customer Service Example #1 Recently, I received an offer in the mail from my cable company, suddenLink. The offer was for an updated TiVo for $12/mo. Normally I ignore offers like this one because I already have the service they’re offering and many times advertisers are offering alternatives to what is already an excellent product offering. I tend to exhibit a high level of loyalty to the products and brands that I use. In this case, we were looking to upgrade our TiVo and this deal is attractive for several reasons: I don’t want to pay a huge amount up-front for the device, so paying a monthly amount for the device is attractive to me. My entertainment is almost all on a single invoice. I’m no longer going to be billed by suddenLink and TiVo. TiVo is still involved, so I am still loyal to the brand I love. I have resisted moving to other DVRs and services for over a decade. I called suddenLink to order the new TiVo and was rewarded with great customer service. In fact, I can’t remember ever getting poor customer service from suddenLink. They are always there to answer my technical support questions and they are very responsive to outages. Then I called TiVo. First of all, I chose the option on the phone system to change or cancel my service, which was consequently met by an inordinate hold time. (I’m calling this time inordinate because I get through very quickly if I want to purchase something.) This is a trend that I’ve noticed with companies – if you want me to be loyal to you, it should be just as easy to cancel your service as it is to purchase it. Because, I should never be cancelling because I am unhappy. And, if you ever want my business again, or more importantly a reference, then you’d better make the exit door open just as easy as the enter door. After quite some time on hold, I talked to “Victor” who was very courteous. Victor canceled my service and then told me that I could keep my current TiVo and transfer recorded programs to it from the new TiVo.  Cool I said, but what about the cost?  He said there was no extra cost.  This was also attractive to me because I paid for my TiVo and it would be good to use it for something at least.  That was four months ago. This month I noticed that TiVo was still charging me for my original service. I was a little upset, but I decided to give them the benefit of the doubt. After all, I am a loyal TiVo customer and I have resisted moving to other solutions for over a decade. I’m sure they will do whatever it takes to keep my business, through TiVo or through suddenLink. After quite some time on hold, I was able to talk to a customer service representative, “Les”. I explained that I am a loyal TiVo customer, but I purchased this deal through my cable provider. I’m still with TiVo, I just wanted a single bill and to take advantage of the pay-over-time option. “Les” told me that he was very sorry to hear that I’m leaving TiVo, to which I responded again that I wasn’t leaving TiVo, I just want one invoice, and to take advantage of the pay-over-time. So, after explaining that I requested a termination of the non-suddenLink account (TiVo can see both of course), I was put on hold again for quite some time while my refund was “approved”.  “Les” said that he could see my cancellation request back in July. Note that it is now November, so they have billed me inappropriately four times. After quite some time, he came back on the line and told me that he was able to “get me most of my money back.” He got approval to refund 90 days. Even though I requested cancellation of one of my accounts, TiVo has that cancellation request on file and they admit overbilling me, I am going to get “most” of my money back. To top this experience off, when we were ready to hang up, “Les” told me that he was sorry to see me go and that he hoped I would come back to TiVo again. Again, I explained to “Les” that I have not left TiVo. I am just paying them through suddenLink. At that point, he went into a small dissertation about how this is a special arrangement they have with suddenLink and very few others. He made me feel like I was doing something wrong. Why should I feel that way? TiVo made the deal with suddenLink, not me, and the deal seemed like a good compromise for me to be able to get what I need. Here is what TiVo Customer Service accomplished on those two calls – I no longer feel like I need to be loyal to the TiVo brand or service. If I had been treated better on these two calls, I would still be recommending TiVo to my friends. They would still be getting revenue from a loyal customer, who paid the same rate for over a decade, and this article wouldn’t be here for you to read. Interesting… In my opinion, if you want brand loyalty, be loyal to your customers!

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• MVVM - how to make creating viewmodels at runtime less painfull

  - by Mr Happy

  I apologize for the long question, it reads a bit as a rant, but I promise it's not! I've summarized my question(s) below In the MVC world, things are straightforward. The Model has state, the View shows the Model, and the Controller does stuff to/with the Model (basically), a controller has no state. To do stuff the Controller has some dependencies on web services, repository, the lot. When you instantiate a controller you care about supplying those dependencies, nothing else. When you execute an action (method on Controller), you use those dependencies to retrieve or update the Model or calling some other domain service. If there's any context, say like some user wants to see the details of a particular item, you pass the Id of that item as parameter to the Action. Nowhere in the Controller is there any reference to any state. So far so good. Enter MVVM. I love WPF, I love data binding. I love frameworks that make data binding to ViewModels even easier (using Caliburn Micro a.t.m.). I feel things are less straightforward in this world though. Let's do the exercise again: the Model has state, the View shows the ViewModel, and the ViewModel does stuff to/with the Model (basically), a ViewModel does have state! (to clarify; maybe it delegates all the properties to one or more Models, but that means it must have a reference to the model one way or another, which is state in itself) To do stuff the ViewModel has some dependencies on web services, repository, the lot. When you instantiate a ViewModel you care about supplying those dependencies, but also the state. And this, ladies and gentlemen, annoys me to no end. Whenever you need to instantiate a ProductDetailsViewModel from the ProductSearchViewModel (from which you called the ProductSearchWebService which in turn returned IEnumerable<ProductDTO>, everybody still with me?), you can do one of these things: call new ProductDetailsViewModel(productDTO, _shoppingCartWebService /* dependcy */);, this is bad, imagine 3 more dependencies, this means the ProductSearchViewModel needs to take on those dependencies as well. Also changing the constructor is painfull. call _myInjectedProductDetailsViewModelFactory.Create().Initialize(productDTO);, the factory is just a Func, they are easily generated by most IoC frameworks. I think this is bad because Init methods are a leaky abstraction. You also can't use the readonly keyword for fields that are set in the Init method. I'm sure there are a few more reasons. call _myInjectedProductDetailsViewModelAbstractFactory.Create(productDTO); So... this is the pattern (abstract factory) that is usually recommended for this type of problem. I though it was genious since it satisfies my craving for static typing, until I actually started using it. The amount of boilerplate code is I think too much (you know, apart from the ridiculous variable names I get use). For each ViewModel that needs runtime parameters you'll get two extra files (factory interface and implementation), and you need to type the non-runtime dependencies like 4 extra times. And each time the dependencies change, you get to change it in the factory as well. It feels like I don't even use an DI container anymore. (I think Castle Windsor has some kind of solution for this [with it's own drawbacks, correct me if I'm wrong]). do something with anonymous types or dictionary. I like my static typing. So, yeah. Mixing state and behavior in this way creates a problem which don't exist at all in MVC. And I feel like there currently isn't a really adequate solution for this problem. Now I'd like to observe some things: People actually use MVVM. So they either don't care about all of the above, or they have some brilliant other solution. I haven't found an indepth example of MVVM with WPF. For example, the NDDD-sample project immensely helped me understand some DDD concepts. I'd really like it if someone could point me in the direction of something similar for MVVM/WPF. Maybe I'm doing MVVM all wrong and I should turn my design upside down. Maybe I shouldn't have this problem at all. Well I know other people have asked the same question so I think I'm not the only one. To summarize Am I correct to conclude that having the ViewModel being an integration point for both state and behavior is the reason for some difficulties with the MVVM pattern as a whole? Is using the abstract factory pattern the only/best way to instantiate a ViewModel in a statically typed way? Is there something like an in depth reference implementation available? Is having a lot of ViewModels with both state/behavior a design smell?

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• Migrating Core Data to new UIManagedDocument in iOS 5

  - by samerpaul

  I have an app that has been on the store since iOS 3.1, so there is a large install base out there that still uses Core Data loaded up in my AppDelegate. In the most recent set of updates, I raised the minimum version to 4.3 but still kept the same way of loading the data. Recently, I decided it's time to make the minimum version 5.1 (especially with 6 around the corner), so I wanted to start using the new fancy UIManagedDocument way of using Core Data. The issue with this though is that the old database file is still sitting in the iOS app, so there is no migrating to the new document. You have to basically subclass UIManagedDocument with a new model class, and override a couple of methods to do it for you. Here's a tutorial on what I did for my app TimeTag.  Step One: Add a new class file in Xcode and subclass "UIManagedDocument" Go ahead and also add a method to get the managedObjectModel out of this class. It should look like:   @interface TimeTagModel : UIManagedDocument   - (NSManagedObjectModel *)managedObjectModel;   @end   Step two: Writing the methods in the implementation file (.m) I first added a shortcut method for the applicationsDocumentDirectory, which returns the URL of the app directory.  - (NSURL *)applicationDocumentsDirectory {     return [[[NSFileManagerdefaultManager] URLsForDirectory:NSDocumentDirectoryinDomains:NSUserDomainMask] lastObject]; }   The next step was to pull the managedObjectModel file itself (.momd file). In my project, it's called "minimalTime". - (NSManagedObjectModel *)managedObjectModel {     NSString *path = [[NSBundlemainBundle] pathForResource:@"minimalTime"ofType:@"momd"];     NSURL *momURL = [NSURL fileURLWithPath:path];     NSManagedObjectModel *managedObjectModel = [[NSManagedObjectModel alloc] initWithContentsOfURL:momURL];          return managedObjectModel; }   After that, I need to check for a legacy installation and migrate it to the new UIManagedDocument file instead. This is the overridden method: - (BOOL)configurePersistentStoreCoordinatorForURL:(NSURL *)storeURL ofType:(NSString *)fileType modelConfiguration:(NSString *)configuration storeOptions:(NSDictionary *)storeOptions error:(NSError **)error {     // If legacy store exists, copy it to the new location     NSURL *legacyPersistentStoreURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:@"minimalTime.sqlite"];          NSFileManager* fileManager = [NSFileManagerdefaultManager];     if ([fileManager fileExistsAtPath:legacyPersistentStoreURL.path])     {         NSLog(@"Old db exists");         NSError* thisError = nil;         [fileManager replaceItemAtURL:storeURL withItemAtURL:legacyPersistentStoreURL backupItemName:niloptions:NSFileManagerItemReplacementUsingNewMetadataOnlyresultingItemURL:nilerror:&thisError];     }          return [superconfigurePersistentStoreCoordinatorForURL:storeURL ofType:fileType modelConfiguration:configuration storeOptions:storeOptions error:error]; }   Basically what's happening above is that it checks for the minimalTime.sqlite file inside the app's bundle on the iOS device.  If the file exists, it tells you inside the console, and then tells the fileManager to replace the storeURL (inside the method parameter) with the legacy URL. This basically gives your app access to all the existing data the user has generated (otherwise they would load into a blank app, which would be disastrous). It returns a YES if successful (by calling it's [super] method). Final step: Actually load this database Due to how my app works, I actually have to load the database at launch (instead of shortly after, which would be ideal). I call a method called loadDatabase, which looks like this: -(void)loadDatabase {     static dispatch_once_t onceToken;          // Only do this once!     dispatch_once(&onceToken, ^{         // Get the URL         // The minimalTimeDB name is just something I call it         NSURL *url = [[selfapplicationDocumentsDirectory] URLByAppendingPathComponent:@"minimalTimeDB"];         // Init the TimeTagModel (our custom class we wrote above) with the URL         self.timeTagDB = [[TimeTagModel alloc] initWithFileURL:url];           // Setup the undo manager if it's nil         if (self.timeTagDB.undoManager == nil){             NSUndoManager *undoManager = [[NSUndoManager  alloc] init];             [self.timeTagDB setUndoManager:undoManager];         }                  // You have to actually check to see if it exists already (for some reason you can't just call "open it, and if it's not there, create it")         if ([[NSFileManagerdefaultManager] fileExistsAtPath:[url path]]) {             // If it does exist, try to open it, and if it doesn't open, let the user (or at least you) know!             [self.timeTagDB openWithCompletionHandler:^(BOOL success){                 if (!success) {                     // Handle the error.                     NSLog(@"Error opening up the database");                 }                 else{                     NSLog(@"Opened the file--it already existed");                     [self refreshData];                 }             }];         }         else {             // If it doesn't exist, you need to attempt to create it             [self.timeTagDBsaveToURL:url forSaveOperation:UIDocumentSaveForCreatingcompletionHandler:^(BOOL success){                 if (!success) {                     // Handle the error.                     NSLog(@"Error opening up the database");                 }                 else{                     NSLog(@"Created the file--it did not exist");                     [self refreshData];                 }             }];         }     }); }   If you're curious what refreshData looks like, it sends out a NSNotification that the database has been loaded: -(void)refreshData {     NSNotification* refreshNotification = [NSNotificationnotificationWithName:kNotificationCenterRefreshAllDatabaseData object:self.timeTagDB.managedObjectContext  userInfo:nil];     [[NSNotificationCenter defaultCenter] postNotification:refreshNotification];     }   The kNotificationCenterRefreshAllDatabaseData is just a constant I have defined elsewhere that keeps track of all the NSNotification names I use. I pass the managedObjectContext of the newly created file so that my view controllers can have access to it, and start passing it around to one another. The reason we do this as a Notification is because this is being run in the background, so we can't know exactly when it finishes. Make sure you design your app for this! Have some kind of loading indicator, or make sure your user can't attempt to create a record before the database actually exists, because it will crash the app.

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• Is Data Science “Science”?

  - by BuckWoody

  I hold the term “science” in very high esteem. I grew up on the Space Coast in Florida, and eventually worked at the Kennedy Space Center, surrounded by very intelligent people who worked in various scientific fields. Recently a new term has entered the computing dialog – “Data Scientist”. Since it’s not a standard term, it has a lot of definitions, and in fact has been disputed as a correct term. After all, the reasoning goes, if there’s no such thing as “Data Science” then how can there be a Data Scientist? This argument has been made before, albeit with a different term – “Computer Science”. In Peter Denning’s excellent article “Is Computer Science Science” (April  2005/Vol. 48, No. 4 COMMUNICATIONS OF THE ACM) there are many points that separate “science” from “engineering” and even “art”.  I won’t repeat the content of that article here (I recommend you read it on your own) but will leverage the points he makes there. Definition of Science To ask the question “is data science ‘science’” then we need to start with a definition of terms. Various references put the definition into the same basic areas: Study of the physical world Systematic and/or disciplined study of a subject area ...and then they include the things studied, the bodies of knowledge and so on. The word itself comes from Latin, and means merely “to know” or “to study to know”. Greek divides knowledge further into “truth” (episteme), and practical use or effects (tekhne). Normally computing falls into the second realm. Definition of Data Science And now a more controversial definition: Data Science. This term is so new and perhaps so niche that the major dictionaries haven’t yet picked it up (my OED reference is older – can’t afford to pop for the online registration at present). Researching the term's general use I created an amalgam of the definitions this way: “Studying and applying mathematical and other techniques to derive information from complex data sets.” Using this definition, data science certainly seems to be science - it's learning about and studying some object or area using systematic methods. But implicit within the definition is the word “application”, which makes the process more akin to engineering or even technology than science. In fact, I find that using these techniques – and data itself – part of science, not science itself. I leave out the concept of studying data patterns or algorithms as part of this discipline. That is actually a domain I see within research, mathematics or computer science. That of course is a type of science, but does not seek for practical applications. As part of the argument against calling it “Data Science”, some point to the scientific method of creating a hypothesis, testing with controls, testing results against the hypothesis, and documenting for repeatability.  These are not steps that we often take in working with data. We normally start with a question, and fit patterns and algorithms to predict outcomes and find correlations. In this way Data Science is more akin to statistics (and in fact makes heavy use of them) in the process rather than starting with an assumption and following on with it. So, is Data Science “Science”? I’m uncertain – and I’m uncertain it matters. Even if we are facing rampant “title inflation” these days (does anyone introduce themselves as a secretary or supervisor anymore?) I can tolerate the term at least from the intent that we use data to study problems across a wide spectrum, rather than restricting it to a single domain. And I also understand those who have worked hard to achieve the very honorable title of “scientist” who have issues with those who borrow the term without asking. What do you think? Science, or not? Does it matter?

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