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• Tools and Utilities for the .NET Developer

  - by mbcrump

  Tweet this list! Add a link to my site to your bookmarks to quickly find this page again! Add me to twitter! This is a list of the tools/utilities that I use to do my job/hobby. I wanted this page to load fast and contain information that only you care about. If I have missed a tool that you like, feel free to contact me and I will add it to the list. Also, this list took a lot of time to complete. Please do not steal my work, if you like the page then please link back to my site. I will keep the links/information updated as new tools/utilities are created.  Windows/.NET Development – This is a list of tools that any Windows/.NET developer should have in his bag. I have used at some point in my career everything listed on this page and below is the tools worth keeping. Name Description License AnkhSVN Subversion support for Visual Studio. It also works with VS2010. Free Aurora XAML Designer One of the best XAML creation tools available. Has a ton of built in templates that you can copy/paste into VS2010. COST/Trial BeyondCompare Beyond Compare 3 is the ideal tool for comparing files and folders on your Windows or Linux system. Visualize changes in your code and carefully reconcile them. COST/Trial BuildIT Automated Task Tool Its main purpose is to automate tasks, whether it is the final packaging of a product, an automated daily build, maybe sending out a mailing list, even backing-up files. Free C Sharper for VB Convert VB to C#. COST CLRProfiler Analyze and improve the behavior of your .NET app. Free CodeRush Direct competitor to ReSharper, contains similar feature. This is one of those decide for yourself. COST/Trial Disk2VHD Disk2vhd is a utility that creates VHD (Virtual Hard Disk - Microsoft's Virtual Machine disk format) versions of physical disks for use in Microsoft Virtual PC or Microsoft Hyper-V virtual machines (VMs). Free Eazfuscator.NET Is a free obfuscator for .NET. The main purpose is to protect intellectual property of software. Free EQATEC Profiler Make your .NET app run faster. No source code changes are needed. Just point the profiler to your app, run the modified code, and get a visual report. COST Expression Studio 3/4 Comes with Web, Blend, Sketch Flow and more. You can create websites, produce beautiful XAML and more. COST/Trial Expresso The award-winning Expresso editor is equally suitable as a teaching tool for the beginning user of regular expressions or as a full-featured development environment for the experienced programmer or web designer with an extensive knowledge of regular expressions. Free Fiddler Fiddler is a web debugging proxy which logs all HTTP(s) traffic between your computer and the internet. Free Firebug Powerful Web development tool. If you build websites, you will need this. Free FxCop FxCop is an application that analyzes managed code assemblies (code that targets the .NET Framework common language runtime) and reports information about the assemblies, such as possible design, localization, performance, and security improvements. Free GAC Browser and Remover Easy way to remove multiple assemblies from the GAC. Assemblies registered by programs like Install Shield can also be removed. Free GAC Util The Global Assembly Cache tool allows you to view and manipulate the contents of the global assembly cache and download cache. Free HelpScribble Help Scribble is a full-featured, easy-to-use help authoring tool for creating help files from start to finish. You can create Win Help (.hlp) files, HTML Help (.chm) files, a printed manual and online documentation (on a web site) all from the same Help Scribble project. COST/Trial IETester IETester is a free Web Browser that allows you to have the rendering and JavaScript engines of IE9 preview, IE8, IE7 IE 6 and IE5.5 on Windows 7, Vista and XP, as well as the installed IE in the same process. Free iTextSharp iText# (iTextSharp) is a port of the iText open source java library for PDF generation written entirely in C# for the .NET platform. Use the iText mailing list to get support. Free Kaxaml Kaxaml is a lightweight XAML editor that gives you a "split view" so you can see both your XAML and your rendered content. Free LINQPad LinqPad lets you interactively query databases in a LINQ. Free Linquer Many programmers are familiar with SQL and will need a help in the transition to LINQ. Sometimes there are complicated queries to be written and Linqer can help by converting SQL scripts to LINQ. COST/Trial LiquidXML Liquid XML Studio 2010 is an advanced XML developers toolkit and IDE, containing all the tools needed for designing and developing XML schema and applications. COST/Trial Log4Net log4net is a tool to help the programmer output log statements to a variety of output targets. log4net is a port of the excellent log4j framework to the .NET runtime. We have kept the framework similar in spirit to the original log4j while taking advantage of new features in the .NET runtime. For more information on log4net see the features document. Free Microsoft Web Platform Installer The Microsoft Web Platform Installer 2.0 (Web PI) is a free tool that makes getting the latest components of the Microsoft Web Platform, including Internet Information Services (IIS), SQL Server Express, .NET Framework and Visual Web Developer easy. Free Mono Development Don't have Visual Studio - no problem! This is an open Source C# and .NET development environment for Linux, Windows, and Mac OS X Free Net Mass Downloader While it’s great that Microsoft has released the .NET Reference Source Code, you can only get it one file at a time while you’re debugging. If you’d like to batch download it for reading or to populate the cache, you’d have to write a program that instantiated and called each method in the Framework Class Library. Fortunately, .NET Mass Downloader comes to the rescue! Free nMap Nmap ("Network Mapper") is a free and open source (license) utility for network exploration or security auditing. Many systems and network administrators also find it useful for tasks such as network inventory, managing service upgrade schedules, and monitoring host or service uptime. Free NoScript (Firefox add-in) The NoScript Firefox extension provides extra protection for Firefox, Flock, Seamonkey and other Mozilla-based browsers: this free, open source add-on allows JavaScript, Java and Flash and other plug-ins to be executed only by trusted web sites of your choice (e.g. your online bank), and provides the most powerful Anti-XSS protection available in a browser. Free NotePad 2 Notepad2, a fast and light-weight Notepad-like text editor with syntax highlighting. This program can be run out of the box without installation, and does not touch your system's registry. Free PageSpy PageSpy is a small add-on for Internet Explorer that allows you to select any element within a webpage, select an option in the context menu, and view detailed information about both the coding behind the page and the element you selected. Free Phrase Express PhraseExpress manages your frequently used text snippets in customizable categories for quick access. Free PowerGui PowerGui is a free community for PowerGUI, a graphical user interface and script editor for Microsoft Windows PowerShell! Free Powershell Comes with Win7, but you can automate tasks by using the .NET Framework. Great for network admins. Free Process Explorer Ever wondered which program has a particular file or directory open? Now you can find out. Process Explorer shows you information about which handles and DLLs processes have opened or loaded. Also, included in the SysInterals Suite. Free Process Monitor Process Monitor is an advanced monitoring tool for Windows that shows real-time file system, Registry and process/thread activity. Free Reflector Explore and analyze compiled .NET assemblies, viewing them in C#, Visual Basic, and IL. This is an Essential for any .NET developer. Free Regular Expression Library Stuck on a Regular Expression but you think someone has already figured it out? Chances are they have. Free Regulator Regulator makes Regular Expressions easy. This is a must have for a .NET Developer. Free RenameMaestro RenameMaestro is probably the easiest batch file renamer you'll find to instantly rename multiple files COST ReSharper The one program that I cannot live without. Supports VS2010 and offers simple refactoring, code analysis/assistance/cleanup/templates. One of the few applications that is worth the $$$. COST/Trial ScrewTurn Wiki ScrewTurn Wiki allows you to create, manage and share wikis. A wiki is a collaboratively-edited, information-centered website: the most famous is Wikipedia. Free SharpDevelop What is #develop? SharpDevelop is a free IDE for C# and VB.NET projects on Microsoft's .NET platform. Free Show Me The Template Show Me The Template is a tool for exploring the templates, be their data, control or items panel, that comes with the controls built into WPF for all 6 themes. Free SnippetCompiler Compiles code snippets without opening Visual Studio. It does not support .NET 4. Free SQL Prompt SQL Prompt is a plug-in that increases how fast you can work with SQL. It provides code-completion for SQL server, reformatting, db schema information and snippets. Awesome! COST/Trial SQLinForm SQLinForm is an automatic SQL code formatter for all major databases  including ORACLE, SQL Server, DB2, UDB, Sybase, Informix, PostgreSQL, Teradata, MySQL, MS Access etc. with over 70 formatting options. COST/OnlineFree SSMS Tools SSMS Tools Pack is an add-in for Microsoft SQL Server Management Studio (SSMS) including SSMS Express. Free Storm STORM is a free and open source tool for testing web services. Free Telerik Code Convertor Convert code from VB to C Sharp and Vice Versa. Free TurtoiseSVN TortoiseSVN is a really easy to use Revision control / version control / source control software for Windows.Since it's not an integration for a specific IDE you can use it with whatever development tools you like. Free UltraEdit UltraEdit is the ideal text, HTML and hex editor, and an advanced PHP, Perl, Java and JavaScript editor for programmers. UltraEdit is also an XML editor including a tree-style XML parser. An industry-award winner, UltraEdit supports disk-based 64-bit file handling (standard) on 32-bit Windows platforms (Windows 2000 and later). COST/Trial Virtual Windows XP Comes with some W7 version and allows you to run WinXP along side W7. Free VirtualBox Virtualization by Sun Microsystems. You can virtualize Windows, Linux and more. Free Visual Log Parser SQL queries against a variety of log files and other system data sources. Free WinMerge WinMerge is an Open Source differencing and merging tool for Windows. WinMerge can compare both folders and files, presenting differences in a visual text format that is easy to understand and handle. Free Wireshark Wireshark is one of the best network protocol analyzer's for Unix and windows. This has been used several times to get me out of a bind. Free XML Notepad 07 Old, but still one of my favorite XML viewers. Free Productivity Tools – This is the list of tools that I use to save time or quickly navigate around Windows. Name Description License AutoHotKey Automate almost anything by sending keystrokes and mouse clicks. You can write a mouse or keyboard macro by hand or use the macro recorder. Free CLCL CLCL is clipboard caching utility. Free Ditto Ditto is an extension to the standard windows clipboard. It saves each item placed on the clipboard allowing you access to any of those items at a later time. Ditto allows you to save any type of information that can be put on the clipboard, text, images, html, custom formats, ..... Free Evernote Remember everything from notes to photos. It will synch between computers/devices. Free InfoRapid Inforapid is a search tool that will display all you search results in a html like browser. If you click on a word in that browser, it will start another search to the word you clicked on. Handy if you want to trackback something to it's true origin. The word you looked for will be highlighted in red. Clicking on the red word will open the containing file in a text based viewer. Clicking on any word in the opened document will start another search on that word. Free KatMouse The prime purpose of the KatMouse utility is to enhance the functionality of mice with a scroll wheel, offering 'universal' scrolling: moving the mouse wheel will scroll the window directly beneath the mouse cursor (not the one with the keyboard focus, which is default on Windows OSes). This is a major increase in the usefulness of the mouse wheel. Free ScreenR Instant Screencast with nothing to download. Works with Mac or PC and free. Free Start++ Start++ is an enhancement for the Start Menu in Windows Vista. It also extends the Run box and the command-line with customizable commands.  For example, typing "w Windows Vista" will take you to the Windows Vista page on Wikipedia! Free Synergy Synergy lets you easily share a single mouse and keyboard between multiple computers with different operating systems, each with its own display, without special hardware. It's intended for users with multiple computers on their desk since each system uses its own monitor(s). Free Texter Texter lets you define text substitution hot strings that, when triggered, will replace hotstring with a larger piece of text. By entering your most commonly-typed snippets of text into Texter, you can save countless keystrokes in the course of the day. Free Total Commander File handling, FTP, Archive handling and much more. Even works with Win3.11. COST/Trial Available Wizmouse WizMouse is a mouse enhancement utility that makes your mouse wheel work on the window currently under the mouse pointer, instead of the currently focused window. This means you no longer have to click on a window before being able to scroll it with the mouse wheel. This is a far more comfortable and practical way to make use of the mouse wheel. Free Xmarks Bookmark sync and search between computers. Free General Utilities – This is a list for power user users or anyone that wants more out of Windows. I usually install a majority of these whenever I get a new system. Name Description License µTorrent µTorrent is a lightweight and efficient BitTorrent client for Windows or Mac with many features. I use this for downloading LEGAL media. Free Audacity Audacity® is free, open source software for recording and editing sounds. It is available for Mac OS X, Microsoft Windows, GNU/Linux, and other operating systems. Learn more about Audacity... Also check our Wiki and Forum for more information. Free AVast Free FREE Antivirus. Free CD Burner XP Pro CDBurnerXP is a free application to burn CDs and DVDs, including Blu-Ray and HD-DVDs. It also includes the feature to burn and create ISOs, as well as a multilanguage interface. Free CDEX You can extract digital audio CDs into mp3/wav. Free Combofix Combofix is a freeware (a legitimate spyware remover created by sUBs), Combofix was designed to scan a computer for known malware, spyware (SurfSideKick, QooLogic, and Look2Me as well as any other combination of the mentioned spyware applications) and remove them. Free Cpu-Z Provides information about some of the main devices of your system. Free Cropper Cropper is a screen capture utility written in C#. It makes it fast and easy to grab parts of your screen. Use it to easily crop out sections of vector graphic files such as Fireworks without having to flatten the files or open in a new editor. Use it to easily capture parts of a web site, including text and images. It's also great for writing documentation that needs images of your application or web site. Free DropBox Drag and Drop files to sync between computers. Free DVD-Fab Converts/Copies DVDs/Blu-Ray to different formats. (like mp4, mkv, avi) COST/Trial Available FastStone Capture FastStone Capture is a powerful, lightweight, yet full-featured screen capture tool that allows you to easily capture and annotate anything on the screen including windows, objects, menus, full screen, rectangular/freehand regions and even scrolling windows/web pages. Free ffdshow FFDShow is a DirectShow decoding filter for decompressing DivX, XviD, H.264, FLV1, WMV, MPEG-1 and MPEG-2, MPEG-4 movies. Free Filezilla FileZilla Client is a fast and reliable cross-platform FTP, FTPS and SFTP client with lots of useful features and an intuitive graphical user interface. You can also download a server version. Free FireFox Web Browser, do you really need an explanation? Free FireGestures A customizable mouse gestures extension which enables you to execute various commands and user scripts with five types of gestures. Free FoxIt Reader Light weight PDF viewer. You should install this with the advanced setting or it will install a toolbar and setup some shortcuts. Free gSynchIt Synch Gmail and Outlook. Even supports Outlook 2010 32/64 bit COST/Trial Available Hulu Desktop At home or in a hotel, this has replaced my cable/satellite subscription. Free ImgBurn ImgBurn is a lightweight CD / DVD / HD DVD / Blu-ray burning application that everyone should have in their toolkit! Free Infrarecorder InfraRecorder is a free CD/DVD burning solution for Microsoft Windows. It offers a wide range of powerful features; all through an easy to use application interface and Windows Explorer integration. Free KeePass KeePass is a free open source password manager, which helps you to manage your passwords in a secure way. Free LastPass Another password management, synchronize between browsers, automatic form filling and more. Free Live Essentials One download and lots of programs including Mail, Live Writer, Movie Maker and more! Free Monitores MonitorES is a small windows utility that helps you to turnoff monitor display when you lock down your machine.Also when you lock your machine, it will pause all your running media programs & set your IM status message to "Away" / Custom message(via options) and restore it back to normal when you back. Free mRemote mRemote is a full-featured, multi-tab remote connections manager. Free Open Office OpenOffice.org 3 is the leading open-source office software suite for word processing, spreadsheets, presentations, graphics, databases and more. It is available in many languages and works on all common computers. It stores all your data in an international open standard format and can also read and write files from other common office software packages. It can be downloaded and used completely free of charge for any purpose. Free Paint.NET Simple, intuitive, and innovative user interface for editing photos. Free Picasa Picasa is free photo editing software from Google that makes your pictures look great. Free Pidgin Pidgin is an easy to use and free chat client used by millions. Connect to AIM, MSN, Yahoo, and more chat networks all at once. Free PING PING is a live Linux ISO, based on the excellent Linux From Scratch (LFS) documentation. It can be burnt on a CD and booted, or integrated into a PXE / RIS environment. Free Putty PuTTY is an SSH and telnet client, developed originally by Simon Tatham for the Windows platform. Free Revo Uninstaller Revo Uninstaller Pro helps you to uninstall software and remove unwanted programs installed on your computer easily! Even if you have problems uninstalling and cannot uninstall them from "Windows Add or Remove Programs" control panel applet.Revo Uninstaller is a much faster and more powerful alternative to "Windows Add or Remove Programs" applet! It has very powerful features to uninstall and remove programs. Free Security Essentials Microsoft Security Essentials is a new, free consumer anti-malware solution for your computer. Free SetupVirtualCloneDrive Virtual CloneDrive works and behaves just like a physical CD/DVD drive, however it exists only virtually. Point to the .ISO file and it appears in Windows Explorer as a Drive. Free Shark 007 Codec Pack Play just about any file format with this download. Also includes my W7 Media Playlist Generator. Free Snagit 9 Screen Capture on steroids. Add arrows, captions, etc to any screenshot. COST/Trial Available SysinternalsSuite Go ahead and download the entire sys internals suite. I have mentioned multiple programs in this suite already. Free TeraCopy TeraCopy is a compact program designed to copy and move files at the maximum possible speed, providing the user with a lot of features. Free for Home TrueCrypt Free open-source disk encryption software for Windows 7/Vista/XP, Mac OS X, and Linux Free TweetDeck Fully featured Twitter client. Free UltraVNC UltraVNC is a powerful, easy to use and free software that can display the screen of another computer (via internet or network) on your own screen. The program allows you to use your mouse and keyboard to control the other PC remotely. It means that you can work on a remote computer, as if you were sitting in front of it, right from your current location. Free Unlocker Unlocks locked files. Pretty simple right? Free VLC Media Player VLC media player is a highly portable multimedia player and multimedia framework capable of reading most audio and video formats Free Windows 7 Media Playlist This program is special to my heart because I wrote it. It has been mentioned on podcast and various websites. It allows you to quickly create wvx video playlist for Windows Media Center. Free WinRAR WinRAR is a powerful archive manager. It can backup your data and reduce the size of email attachments, decompress RAR, ZIP and other files downloaded from Internet and create new archives in RAR and ZIP file format. COST/Trial Available Blogging – I use the following for my blog. Name Description License Insert Code for Windows Live Writer Insert Code for Windows Live Writer will format a snippet of text in a number of programming languages such as C#, HTML, MSH, JavaScript, Visual Basic and TSQL. Free LiveWriter Included in Live Essentials, but the ultimate in Windows Blogging Free PasteAsVSCode Plug-in for Windows Live Writer that pastes clipboard content as Visual Studio code. Preserves syntax highlighting, indentation and background color. Converts RTF, outputted by Visual Studio, into HTML. Free Desktop Management – The list below represent the best in Windows Desktop Management. Name Description License 7 Stacks Allows users to have "stacks" of icons in their taskbar. Free Executor Executor is a multi purpose launcher and a more advanced and customizable version of windows run. Free Fences Fences is a program that helps you organize your desktop and can hide your icons when they are not in use. Free RocketDock Rocket Dock is a smoothly animated, alpha blended application launcher. It provides a nice clean interface to drop shortcuts on for easy access and organization. With each item completely customizable there is no end to what you can add and launch from the dock. Free WindowsTab Tabbing is an essential feature of modern web browsers. Window Tabs brings the productivity of tabbed window management to all of your desktop applications. Free

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• West Wind WebSurge - an easy way to Load Test Web Applications

  - by Rick Strahl

  A few months ago on a project the subject of load testing came up. We were having some serious issues with a Web application that would start spewing SQL lock errors under somewhat heavy load. These sort of errors can be tough to catch, precisely because they only occur under load and not during typical development testing. To replicate this error more reliably we needed to put a load on the application and run it for a while before these SQL errors would flare up. It’s been a while since I’d looked at load testing tools, so I spent a bit of time looking at different tools and frankly didn’t really find anything that was a good fit. A lot of tools were either a pain to use, didn’t have the basic features I needed, or are extravagantly expensive. In  the end I got frustrated enough to build an initially small custom load test solution that then morphed into a more generic library, then gained a console front end and eventually turned into a full blown Web load testing tool that is now called West Wind WebSurge. I got seriously frustrated looking for tools every time I needed some quick and dirty load testing for an application. If my aim is to just put an application under heavy enough load to find a scalability problem in code, or to simply try and push an application to its limits on the hardware it’s running I shouldn’t have to have to struggle to set up tests. It should be easy enough to get going in a few minutes, so that the testing can be set up quickly so that it can be done on a regular basis without a lot of hassle. And that was the goal when I started to build out my initial custom load tester into a more widely usable tool. If you’re in a hurry and you want to check it out, you can find more information and download links here: West Wind WebSurge Product Page Walk through Video Download link (zip) Install from Chocolatey Source on GitHub For a more detailed discussion of the why’s and how’s and some background continue reading. How did I get here? When I started out on this path, I wasn’t planning on building a tool like this myself – but I got frustrated enough looking at what’s out there to think that I can do better than what’s available for the most common simple load testing scenarios. When we ran into the SQL lock problems I mentioned, I started looking around what’s available for Web load testing solutions that would work for our whole team which consisted of a few developers and a couple of IT guys both of which needed to be able to run the tests. It had been a while since I looked at tools and I figured that by now there should be some good solutions out there, but as it turns out I didn’t really find anything that fit our relatively simple needs without costing an arm and a leg… I spent the better part of a day installing and trying various load testing tools and to be frank most of them were either terrible at what they do, incredibly unfriendly to use, used some terminology I couldn’t even parse, or were extremely expensive (and I mean in the ‘sell your liver’ range of expensive). Pick your poison. There are also a number of online solutions for load testing and they actually looked more promising, but those wouldn’t work well for our scenario as the application is running inside of a private VPN with no outside access into the VPN. Most of those online solutions also ended up being very pricey as well – presumably because of the bandwidth required to test over the open Web can be enormous. When I asked around on Twitter what people were using– I got mostly… crickets. Several people mentioned Visual Studio Load Test, and most other suggestions pointed to online solutions. I did get a bunch of responses though with people asking to let them know what I found – apparently I’m not alone when it comes to finding load testing tools that are effective and easy to use. As to Visual Studio, the higher end skus of Visual Studio and the test edition include a Web load testing tool, which is quite powerful, but there are a number of issues with that: First it’s tied to Visual Studio so it’s not very portable – you need a VS install. I also find the test setup and terminology used by the VS test runner extremely confusing. Heck, it’s complicated enough that there’s even a Pluralsight course on using the Visual Studio Web test from Steve Smith. And of course you need to have one of the high end Visual Studio Skus, and those are mucho Dinero ($$$) – just for the load testing that’s rarely an option. Some of the tools are ultra extensive and let you run analysis tools on the target serves which is useful, but in most cases – just plain overkill and only distracts from what I tend to be ultimately interested in: Reproducing problems that occur at high load, and finding the upper limits and ‘what if’ scenarios as load is ramped up increasingly against a site. Yes it’s useful to have Web app instrumentation, but often that’s not what you’re interested in. I still fondly remember early days of Web testing when Microsoft had the WAST (Web Application Stress Tool) tool, which was rather simple – and also somewhat limited – but easily allowed you to create stress tests very quickly. It had some serious limitations (mainly that it didn’t work with SSL),  but the idea behind it was excellent: Create tests quickly and easily and provide a decent engine to run it locally with minimal setup. You could get set up and run tests within a few minutes. Unfortunately, that tool died a quiet death as so many of Microsoft’s tools that probably were built by an intern and then abandoned, even though there was a lot of potential and it was actually fairly widely used. Eventually the tools was no longer downloadable and now it simply doesn’t work anymore on higher end hardware. West Wind Web Surge – Making Load Testing Quick and Easy So I ended up creating West Wind WebSurge out of rebellious frustration… The goal of WebSurge is to make it drop dead simple to create load tests. It’s super easy to capture sessions either using the built in capture tool (big props to Eric Lawrence, Telerik and FiddlerCore which made that piece a snap), using the full version of Fiddler and exporting sessions, or by manually or programmatically creating text files based on plain HTTP headers to create requests. I’ve been using this tool for 4 months now on a regular basis on various projects as a reality check for performance and scalability and it’s worked extremely well for finding small performance issues. I also use it regularly as a simple URL tester, as it allows me to quickly enter a URL plus headers and content and test that URL and its results along with the ability to easily save one or more of those URLs. A few weeks back I made a walk through video that goes over most of the features of WebSurge in some detail: Note that the UI has slightly changed since then, so there are some UI improvements. Most notably the test results screen has been updated recently to a different layout and to provide more information about each URL in a session at a glance. The video and the main WebSurge site has a lot of info of basic operations. For the rest of this post I’ll talk about a few deeper aspects that may be of interest while also giving a glance at how WebSurge works. Session Capturing As you would expect, WebSurge works with Sessions of Urls that are played back under load. Here’s what the main Session View looks like: You can create session entries manually by individually adding URLs to test (on the Request tab on the right) and saving them, or you can capture output from Web Browsers, Windows Desktop applications that call services, your own applications using the built in Capture tool. With this tool you can capture anything HTTP -SSL requests and content from Web pages, AJAX calls, SOAP or REST services – again anything that uses Windows or .NET HTTP APIs. Behind the scenes the capture tool uses FiddlerCore so basically anything you can capture with Fiddler you can also capture with Web Surge Session capture tool. Alternately you can actually use Fiddler as well, and then export the captured Fiddler trace to a file, which can then be imported into WebSurge. This is a nice way to let somebody capture session without having to actually install WebSurge or for your customers to provide an exact playback scenario for a given set of URLs that cause a problem perhaps. Note that not all applications work with Fiddler’s proxy unless you configure a proxy. For example, .NET Web applications that make HTTP calls usually don’t show up in Fiddler by default. For those .NET applications you can explicitly override proxy settings to capture those requests to service calls. The capture tool also has handy optional filters that allow you to filter by domain, to help block out noise that you typically don’t want to include in your requests. For example, if your pages include links to CDNs, or Google Analytics or social links you typically don’t want to include those in your load test, so by capturing just from a specific domain you are guaranteed content from only that one domain. Additionally you can provide url filters in the configuration file – filters allow to provide filter strings that if contained in a url will cause requests to be ignored. Again this is useful if you don’t filter by domain but you want to filter out things like static image, css and script files etc. Often you’re not interested in the load characteristics of these static and usually cached resources as they just add noise to tests and often skew the overall url performance results. In my testing I tend to care only about my dynamic requests. SSL Captures require Fiddler Note, that in order to capture SSL requests you’ll have to install the Fiddler’s SSL certificate. The easiest way to do this is to install Fiddler and use its SSL configuration options to get the certificate into the local certificate store. There’s a document on the Telerik site that provides the exact steps to get SSL captures to work with Fiddler and therefore with WebSurge. Session Storage A group of URLs entered or captured make up a Session. Sessions can be saved and restored easily as they use a very simple text format that simply stored on disk. The format is slightly customized HTTP header traces separated by a separator line. The headers are standard HTTP headers except that the full URL instead of just the domain relative path is stored as part of the 1st HTTP header line for easier parsing. Because it’s just text and uses the same format that Fiddler uses for exports, it’s super easy to create Sessions by hand manually or under program control writing out to a simple text file. You can see what this format looks like in the Capture window figure above – the raw captured format is also what’s stored to disk and what WebSurge parses from. The only ‘custom’ part of these headers is that 1st line contains the full URL instead of the domain relative path and Host: header. The rest of each header are just plain standard HTTP headers with each individual URL isolated by a separator line. The format used here also uses what Fiddler produces for exports, so it’s easy to exchange or view data either in Fiddler or WebSurge. Urls can also be edited interactively so you can modify the headers easily as well: Again – it’s just plain HTTP headers so anything you can do with HTTP can be added here. Use it for single URL Testing Incidentally I’ve also found this form as an excellent way to test and replay individual URLs for simple non-load testing purposes. Because you can capture a single or many URLs and store them on disk, this also provides a nice HTTP playground where you can record URLs with their headers, and fire them one at a time or as a session and see results immediately. It’s actually an easy way for REST presentations and I find the simple UI flow actually easier than using Fiddler natively. Finally you can save one or more URLs as a session for later retrieval. I’m using this more and more for simple URL checks. Overriding Cookies and Domains Speaking of HTTP headers – you can also overwrite cookies used as part of the options. One thing that happens with modern Web applications is that you have session cookies in use for authorization. These cookies tend to expire at some point which would invalidate a test. Using the Options dialog you can actually override the cookie: which replaces the cookie for all requests with the cookie value specified here. You can capture a valid cookie from a manual HTTP request in your browser and then paste into the cookie field, to replace the existing Cookie with the new one that is now valid. Likewise you can easily replace the domain so if you captured urls on west-wind.com and now you want to test on localhost you can do that easily easily as well. You could even do something like capture on store.west-wind.com and then test on localhost/store which would also work. Running Load Tests Once you’ve created a Session you can specify the length of the test in seconds, and specify the number of simultaneous threads to run each session on. Sessions run through each of the URLs in the session sequentially by default. One option in the options list above is that you can also randomize the URLs so each thread runs requests in a different order. This avoids bunching up URLs initially when tests start as all threads run the same requests simultaneously which can sometimes skew the results of the first few minutes of a test. While sessions run some progress information is displayed: By default there’s a live view of requests displayed in a Console-like window. On the bottom of the window there’s a running total summary that displays where you’re at in the test, how many requests have been processed and what the requests per second count is currently for all requests. Note that for tests that run over a thousand requests a second it’s a good idea to turn off the console display. While the console display is nice to see that something is happening and also gives you slight idea what’s happening with actual requests, once a lot of requests are processed, this UI updating actually adds a lot of CPU overhead to the application which may cause the actual load generated to be reduced. If you are running a 1000 requests a second there’s not much to see anyway as requests roll by way too fast to see individual lines anyway. If you look on the options panel, there is a NoProgressEvents option that disables the console display. Note that the summary display is still updated approximately once a second so you can always tell that the test is still running. Test Results When the test is done you get a simple Results display: On the right you get an overall summary as well as breakdown by each URL in the session. Both success and failures are highlighted so it’s easy to see what’s breaking in your load test. The report can be printed or you can also open the HTML document in your default Web Browser for printing to PDF or saving the HTML document to disk. The list on the right shows you a partial list of the URLs that were fired so you can look in detail at the request and response data. The list can be filtered by success and failure requests. Each list is partial only (at the moment) and limited to a max of 1000 items in order to render reasonably quickly. Each item in the list can be clicked to see the full request and response data: This particularly useful for errors so you can quickly see and copy what request data was used and in the case of a GET request you can also just click the link to quickly jump to the page. For non-GET requests you can find the URL in the Session list, and use the context menu to Test the URL as configured including any HTTP content data to send. You get to see the full HTTP request and response as well as a link in the Request header to go visit the actual page. Not so useful for a POST as above, but definitely useful for GET requests. Finally you can also get a few charts. The most useful one is probably the Request per Second chart which can be accessed from the Charts menu or shortcut. Here’s what it looks like:   Results can also be exported to JSON, XML and HTML. Keep in mind that these files can get very large rather quickly though, so exports can end up taking a while to complete. Command Line Interface WebSurge runs with a small core load engine and this engine is plugged into the front end application I’ve shown so far. There’s also a command line interface available to run WebSurge from the Windows command prompt. Using the command line you can run tests for either an individual URL (similar to AB.exe for example) or a full Session file. By default when it runs WebSurgeCli shows progress every second showing total request count, failures and the requests per second for the entire test. A silent option can turn off this progress display and display only the results. The command line interface can be useful for build integration which allows checking for failures perhaps or hitting a specific requests per second count etc. It’s also nice to use this as quick and dirty URL test facility similar to the way you’d use Apache Bench (ab.exe). Unlike ab.exe though, WebSurgeCli supports SSL and makes it much easier to create multi-URL tests using either manual editing or the WebSurge UI. Current Status Currently West Wind WebSurge is still in Beta status. I’m still adding small new features and tweaking the UI in an attempt to make it as easy and self-explanatory as possible to run. Documentation for the UI and specialty features is also still a work in progress. I plan on open-sourcing this product, but it won’t be free. There’s a free version available that provides a limited number of threads and request URLs to run. A relatively low cost license  removes the thread and request limitations. Pricing info can be found on the Web site – there’s an introductory price which is $99 at the moment which I think is reasonable compared to most other for pay solutions out there that are exorbitant by comparison… The reason code is not available yet is – well, the UI portion of the app is a bit embarrassing in its current monolithic state. The UI started as a very simple interface originally that later got a lot more complex – yeah, that never happens, right? Unless there’s a lot of interest I don’t foresee re-writing the UI entirely (which would be ideal), but in the meantime at least some cleanup is required before I dare to publish it :-). The code will likely be released with version 1.0. I’m very interested in feedback. Do you think this could be useful to you and provide value over other tools you may or may not have used before? I hope so – it already has provided a ton of value for me and the work I do that made the development worthwhile at this point. You can leave a comment below, or for more extensive discussions you can post a message on the West Wind Message Board in the WebSurge section Microsoft MVPs and Insiders get a free License If you’re a Microsoft MVP or a Microsoft Insider you can get a full license for free. Send me a link to your current, official Microsoft profile and I’ll send you a not-for resale license. Send any messages to [email protected]. Resources For more info on WebSurge and to download it to try it out, use the following links. West Wind WebSurge Home Download West Wind WebSurge Getting Started with West Wind WebSurge Video© Rick Strahl, West Wind Technologies, 2005-2014Posted in ASP.NET   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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• Capturing and Transforming ASP.NET Output with Response.Filter

  - by Rick Strahl

  During one of my Handlers and Modules session at DevConnections this week one of the attendees asked a question that I didn’t have an immediate answer for. Basically he wanted to capture response output completely and then apply some filtering to the output – effectively injecting some additional content into the page AFTER the page had completely rendered. Specifically the output should be captured from anywhere – not just a page and have this code injected into the page. Some time ago I posted some code that allows you to capture ASP.NET Page output by overriding the Render() method, capturing the HtmlTextWriter() and reading its content, modifying the rendered data as text then writing it back out. I’ve actually used this approach on a few occasions and it works fine for ASP.NET pages. But this obviously won’t work outside of the Page class environment and it’s not really generic – you have to create a custom page class in order to handle the output capture. [updated 11/16/2009 – updated ResponseFilterStream implementation and a few additional notes based on comments] Enter Response.Filter However, ASP.NET includes a Response.Filter which can be used – well to filter output. Basically Response.Filter is a stream through which the OutputStream is piped back to the Web Server (indirectly). As content is written into the Response object, the filter stream receives the appropriate Stream commands like Write, Flush and Close as well as read operations although for a Response.Filter that’s uncommon to be hit. The Response.Filter can be programmatically replaced at runtime which allows you to effectively intercept all output generation that runs through ASP.NET. A common Example: Dynamic GZip Encoding A rather common use of Response.Filter hooking up code based, dynamic  GZip compression for requests which is dead simple by applying a GZipStream (or DeflateStream) to Response.Filter. The following generic routines can be used very easily to detect GZip capability of the client and compress response output with a single line of code and a couple of library helper routines: WebUtils.GZipEncodePage(); which is handled with a few lines of reusable code and a couple of static helper methods: /// <summary> ///Sets up the current page or handler to use GZip through a Response.Filter ///IMPORTANT:  ///You have to call this method before any output is generated! /// </summary> public static void GZipEncodePage() {     HttpResponse Response = HttpContext.Current.Response;     if(IsGZipSupported())     {         stringAcceptEncoding = HttpContext.Current.Request.Headers["Accept-Encoding"];         if(AcceptEncoding.Contains("deflate"))         {             Response.Filter = newSystem.IO.Compression.DeflateStream(Response.Filter,                                        System.IO.Compression.CompressionMode.Compress);             Response.AppendHeader("Content-Encoding", "deflate");         }         else        {             Response.Filter = newSystem.IO.Compression.GZipStream(Response.Filter,                                       System.IO.Compression.CompressionMode.Compress);             Response.AppendHeader("Content-Encoding", "gzip");                            }     }     // Allow proxy servers to cache encoded and unencoded versions separately    Response.AppendHeader("Vary", "Content-Encoding"); } /// <summary> /// Determines if GZip is supported /// </summary> /// <returns></returns> public static bool IsGZipSupported() { string AcceptEncoding = HttpContext.Current.Request.Headers["Accept-Encoding"]; if (!string.IsNullOrEmpty(AcceptEncoding) && (AcceptEncoding.Contains("gzip") || AcceptEncoding.Contains("deflate"))) return true; return false; } GZipStream and DeflateStream are streams that are assigned to Response.Filter and by doing so apply the appropriate compression on the active Response. Response.Filter content is chunked So to implement a Response.Filter effectively requires only that you implement a custom stream and handle the Write() method to capture Response output as it’s written. At first blush this seems very simple – you capture the output in Write, transform it and write out the transformed content in one pass. And that indeed works for small amounts of content. But you see, the problem is that output is written in small buffer chunks (a little less than 16k it appears) rather than just a single Write() statement into the stream, which makes perfect sense for ASP.NET to stream data back to IIS in smaller chunks to minimize memory usage en route. Unfortunately this also makes it a more difficult to implement any filtering routines since you don’t directly get access to all of the response content which is problematic especially if those filtering routines require you to look at the ENTIRE response in order to transform or capture the output as is needed for the solution the gentleman in my session asked for. So in order to address this a slightly different approach is required that basically captures all the Write() buffers passed into a cached stream and then making the stream available only when it’s complete and ready to be flushed. As I was thinking about the implementation I also started thinking about the few instances when I’ve used Response.Filter implementations. Each time I had to create a new Stream subclass and create my custom functionality but in the end each implementation did the same thing – capturing output and transforming it. I thought there should be an easier way to do this by creating a re-usable Stream class that can handle stream transformations that are common to Response.Filter implementations. Creating a semi-generic Response Filter Stream Class What I ended up with is a ResponseFilterStream class that provides a handful of Events that allow you to capture and/or transform Response content. The class implements a subclass of Stream and then overrides Write() and Flush() to handle capturing and transformation operations. By exposing events it’s easy to hook up capture or transformation operations via single focused methods. ResponseFilterStream exposes the following events: CaptureStream, CaptureString Captures the output only and provides either a MemoryStream or String with the final page output. Capture is hooked to the Flush() operation of the stream. TransformStream, TransformString Allows you to transform the complete response output with events that receive a MemoryStream or String respectively and can you modify the output then return it back as a return value. The transformed output is then written back out in a single chunk to the response output stream. These events capture all output internally first then write the entire buffer into the response. TransformWrite, TransformWriteString Allows you to transform the Response data as it is written in its original chunk size in the Stream’s Write() method. Unlike TransformStream/TransformString which operate on the complete output, these events only see the current chunk of data written. This is more efficient as there’s no caching involved, but can cause problems due to searched content splitting over multiple chunks. Using this implementation, creating a custom Response.Filter transformation becomes as simple as the following code. To hook up the Response.Filter using the MemoryStream version event: ResponseFilterStream filter = new ResponseFilterStream(Response.Filter); filter.TransformStream += filter_TransformStream; Response.Filter = filter; and the event handler to do the transformation: MemoryStream filter_TransformStream(MemoryStream ms) { Encoding encoding = HttpContext.Current.Response.ContentEncoding; string output = encoding.GetString(ms.ToArray()); output = FixPaths(output); ms = new MemoryStream(output.Length); byte[] buffer = encoding.GetBytes(output); ms.Write(buffer,0,buffer.Length); return ms; } private string FixPaths(string output) { string path = HttpContext.Current.Request.ApplicationPath; // override root path wonkiness if (path == "/") path = ""; output = output.Replace("\"~/", "\"" + path + "/").Replace("'~/", "'" + path + "/"); return output; } The idea of the event handler is that you can do whatever you want to the stream and return back a stream – either the same one that’s been modified or a brand new one – which is then sent back to as the final response. The above code can be simplified even more by using the string version events which handle the stream to string conversions for you: ResponseFilterStream filter = new ResponseFilterStream(Response.Filter); filter.TransformString += filter_TransformString; Response.Filter = filter; and the event handler to do the transformation calling the same FixPaths method shown above: string filter_TransformString(string output) { return FixPaths(output); } The events for capturing output and capturing and transforming chunks work in a very similar way. By using events to handle the transformations ResponseFilterStream becomes a reusable component and we don’t have to create a new stream class or subclass an existing Stream based classed. By the way, the example used here is kind of a cool trick which transforms “~/” expressions inside of the final generated HTML output – even in plain HTML controls not HTML controls – and transforms them into the appropriate application relative path in the same way that ResolveUrl would do. So you can write plain old HTML like this: <a href=”~/default.aspx”>Home</a>  and have it turned into: <a href=”/myVirtual/default.aspx”>Home</a>  without having to use an ASP.NET control like Hyperlink or Image or having to constantly use: <img src=”<%= ResolveUrl(“~/images/home.gif”) %>” /> in MVC applications (which frankly is one of the most annoying things about MVC especially given the path hell that extension-less and endpoint-less URLs impose). I can’t take credit for this idea. While discussing the Response.Filter issues on Twitter a hint from Dylan Beattie who pointed me at one of his examples which does something similar. I thought the idea was cool enough to use an example for future demos of Response.Filter functionality in ASP.NET next I time I do the Modules and Handlers talk (which was great fun BTW). How practical this is is debatable however since there’s definitely some overhead to using a Response.Filter in general and especially on one that caches the output and the re-writes it later. Make sure to test for performance anytime you use Response.Filter hookup and make sure it' doesn’t end up killing perf on you. You’ve been warned :-}. How does ResponseFilterStream work? The big win of this implementation IMHO is that it’s a reusable  component – so for implementation there’s no new class, no subclassing – you simply attach to an event to implement an event handler method with a straight forward signature to retrieve the stream or string you’re interested in. The implementation is based on a subclass of Stream as is required in order to handle the Response.Filter requirements. What’s different than other implementations I’ve seen in various places is that it supports capturing output as a whole to allow retrieving the full response output for capture or modification. The exception are the TransformWrite and TransformWrite events which operate only active chunk of data written by the Response. For captured output, the Write() method captures output into an internal MemoryStream that is cached until writing is complete. So Write() is called when ASP.NET writes to the Response stream, but the filter doesn’t pass on the Write immediately to the filter’s internal stream. The data is cached and only when the Flush() method is called to finalize the Stream’s output do we actually send the cached stream off for transformation (if the events are hooked up) and THEN finally write out the returned content in one big chunk. Here’s the implementation of ResponseFilterStream: /// <summary> /// A semi-generic Stream implementation for Response.Filter with /// an event interface for handling Content transformations via /// Stream or String. /// <remarks> /// Use with care for large output as this implementation copies /// the output into a memory stream and so increases memory usage. /// </remarks> /// </summary> public class ResponseFilterStream : Stream { /// <summary> /// The original stream /// </summary> Stream _stream; /// <summary> /// Current position in the original stream /// </summary> long _position; /// <summary> /// Stream that original content is read into /// and then passed to TransformStream function /// </summary> MemoryStream _cacheStream = new MemoryStream(5000); /// <summary> /// Internal pointer that that keeps track of the size /// of the cacheStream /// </summary> int _cachePointer = 0; /// <summary> /// /// </summary> /// <param name="responseStream"></param> public ResponseFilterStream(Stream responseStream) { _stream = responseStream; } /// <summary> /// Determines whether the stream is captured /// </summary> private bool IsCaptured { get { if (CaptureStream != null || CaptureString != null || TransformStream != null || TransformString != null) return true; return false; } } /// <summary> /// Determines whether the Write method is outputting data immediately /// or delaying output until Flush() is fired. /// </summary> private bool IsOutputDelayed { get { if (TransformStream != null || TransformString != null) return true; return false; } } /// <summary> /// Event that captures Response output and makes it available /// as a MemoryStream instance. Output is captured but won't /// affect Response output. /// </summary> public event Action<MemoryStream> CaptureStream; /// <summary> /// Event that captures Response output and makes it available /// as a string. Output is captured but won't affect Response output. /// </summary> public event Action<string> CaptureString; /// <summary> /// Event that allows you transform the stream as each chunk of /// the output is written in the Write() operation of the stream. /// This means that that it's possible/likely that the input /// buffer will not contain the full response output but only /// one of potentially many chunks. /// /// This event is called as part of the filter stream's Write() /// operation. /// </summary> public event Func<byte[], byte[]> TransformWrite; /// <summary> /// Event that allows you to transform the response stream as /// each chunk of bytep[] output is written during the stream's write /// operation. This means it's possibly/likely that the string /// passed to the handler only contains a portion of the full /// output. Typical buffer chunks are around 16k a piece. /// /// This event is called as part of the stream's Write operation. /// </summary> public event Func<string, string> TransformWriteString; /// <summary> /// This event allows capturing and transformation of the entire /// output stream by caching all write operations and delaying final /// response output until Flush() is called on the stream. /// </summary> public event Func<MemoryStream, MemoryStream> TransformStream; /// <summary> /// Event that can be hooked up to handle Response.Filter /// Transformation. Passed a string that you can modify and /// return back as a return value. The modified content /// will become the final output. /// </summary> public event Func<string, string> TransformString; protected virtual void OnCaptureStream(MemoryStream ms) { if (CaptureStream != null) CaptureStream(ms); } private void OnCaptureStringInternal(MemoryStream ms) { if (CaptureString != null) { string content = HttpContext.Current.Response.ContentEncoding.GetString(ms.ToArray()); OnCaptureString(content); } } protected virtual void OnCaptureString(string output) { if (CaptureString != null) CaptureString(output); } protected virtual byte[] OnTransformWrite(byte[] buffer) { if (TransformWrite != null) return TransformWrite(buffer); return buffer; } private byte[] OnTransformWriteStringInternal(byte[] buffer) { Encoding encoding = HttpContext.Current.Response.ContentEncoding; string output = OnTransformWriteString(encoding.GetString(buffer)); return encoding.GetBytes(output); } private string OnTransformWriteString(string value) { if (TransformWriteString != null) return TransformWriteString(value); return value; } protected virtual MemoryStream OnTransformCompleteStream(MemoryStream ms) { if (TransformStream != null) return TransformStream(ms); return ms; } /// <summary> /// Allows transforming of strings /// /// Note this handler is internal and not meant to be overridden /// as the TransformString Event has to be hooked up in order /// for this handler to even fire to avoid the overhead of string /// conversion on every pass through. /// </summary> /// <param name="responseText"></param> /// <returns></returns> private string OnTransformCompleteString(string responseText) { if (TransformString != null) TransformString(responseText); return responseText; } /// <summary> /// Wrapper method form OnTransformString that handles /// stream to string and vice versa conversions /// </summary> /// <param name="ms"></param> /// <returns></returns> internal MemoryStream OnTransformCompleteStringInternal(MemoryStream ms) { if (TransformString == null) return ms; //string content = ms.GetAsString(); string content = HttpContext.Current.Response.ContentEncoding.GetString(ms.ToArray()); content = TransformString(content); byte[] buffer = HttpContext.Current.Response.ContentEncoding.GetBytes(content); ms = new MemoryStream(); ms.Write(buffer, 0, buffer.Length); //ms.WriteString(content); return ms; } /// <summary> /// /// </summary> public override bool CanRead { get { return true; } } public override bool CanSeek { get { return true; } } /// <summary> /// /// </summary> public override bool CanWrite { get { return true; } } /// <summary> /// /// </summary> public override long Length { get { return 0; } } /// <summary> /// /// </summary> public override long Position { get { return _position; } set { _position = value; } } /// <summary> /// /// </summary> /// <param name="offset"></param> /// <param name="direction"></param> /// <returns></returns> public override long Seek(long offset, System.IO.SeekOrigin direction) { return _stream.Seek(offset, direction); } /// <summary> /// /// </summary> /// <param name="length"></param> public override void SetLength(long length) { _stream.SetLength(length); } /// <summary> /// /// </summary> public override void Close() { _stream.Close(); } /// <summary> /// Override flush by writing out the cached stream data /// </summary> public override void Flush() { if (IsCaptured && _cacheStream.Length > 0) { // Check for transform implementations _cacheStream = OnTransformCompleteStream(_cacheStream); _cacheStream = OnTransformCompleteStringInternal(_cacheStream); OnCaptureStream(_cacheStream); OnCaptureStringInternal(_cacheStream); // write the stream back out if output was delayed if (IsOutputDelayed) _stream.Write(_cacheStream.ToArray(), 0, (int)_cacheStream.Length); // Clear the cache once we've written it out _cacheStream.SetLength(0); } // default flush behavior _stream.Flush(); } /// <summary> /// /// </summary> /// <param name="buffer"></param> /// <param name="offset"></param> /// <param name="count"></param> /// <returns></returns> public override int Read(byte[] buffer, int offset, int count) { return _stream.Read(buffer, offset, count); } /// <summary> /// Overriden to capture output written by ASP.NET and captured /// into a cached stream that is written out later when Flush() /// is called. /// </summary> /// <param name="buffer"></param> /// <param name="offset"></param> /// <param name="count"></param> public override void Write(byte[] buffer, int offset, int count) { if ( IsCaptured ) { // copy to holding buffer only - we'll write out later _cacheStream.Write(buffer, 0, count); _cachePointer += count; } // just transform this buffer if (TransformWrite != null) buffer = OnTransformWrite(buffer); if (TransformWriteString != null) buffer = OnTransformWriteStringInternal(buffer); if (!IsOutputDelayed) _stream.Write(buffer, offset, buffer.Length); } } The key features are the events and corresponding OnXXX methods that handle the event hookups, and the Write() and Flush() methods of the stream implementation. All the rest of the members tend to be plain jane passthrough stream implementation code without much consequence. I do love the way Action<t> and Func<T> make it so easy to create the event signatures for the various events – sweet. A few Things to consider Performance Response.Filter is not great for performance in general as it adds another layer of indirection to the ASP.NET output pipeline, and this implementation in particular adds a memory hit as it basically duplicates the response output into the cached memory stream which is necessary since you may have to look at the entire response. If you have large pages in particular this can cause potentially serious memory pressure in your server application. So be careful of wholesale adoption of this (or other) Response.Filters. Make sure to do some performance testing to ensure it’s not killing your app’s performance. Response.Filter works everywhere A few questions came up in comments and discussion as to capturing ALL output hitting the site and – yes you can definitely do that by assigning a Response.Filter inside of a module. If you do this however you’ll want to be very careful and decide which content you actually want to capture especially in IIS 7 which passes ALL content – including static images/CSS etc. through the ASP.NET pipeline. So it is important to filter only on what you’re looking for – like the page extension or maybe more effectively the Response.ContentType. Response.Filter Chaining Originally I thought that filter chaining doesn’t work at all due to a bug in the stream implementation code. But it’s quite possible to assign multiple filters to the Response.Filter property. So the following actually works to both compress the output and apply the transformed content: WebUtils.GZipEncodePage(); ResponseFilterStream filter = new ResponseFilterStream(Response.Filter); filter.TransformString += filter_TransformString; Response.Filter = filter; However the following does not work resulting in invalid content encoding errors: ResponseFilterStream filter = new ResponseFilterStream(Response.Filter); filter.TransformString += filter_TransformString; Response.Filter = filter; WebUtils.GZipEncodePage(); In other words multiple Response filters can work together but it depends entirely on the implementation whether they can be chained or in which order they can be chained. In this case running the GZip/Deflate stream filters apparently relies on the original content length of the output and chokes when the content is modified. But if attaching the compression first it works fine as unintuitive as that may seem. Resources Download example code Capture Output from ASP.NET Pages © Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET  

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• SQLAuthority News – A Successful Community TechDays at Ahmedabad – December 11, 2010

  - by pinaldave

  We recently had one of the best community events in Ahmedabad. We were fortunate that we had SQL Experts from around the world to have presented at this event. This gathering was very special because besides Jacob Sebastian and myself, we had two other speakers traveling all the way from Florida (Rushabh Mehta) and Bangalore (Vinod Kumar).There were a total of nearly 170 attendees and the event was blast. Here are the details of the event. Pinal Dave Presenting at Community Tech Days On the day of the event, it seemed to be the coldest day in Ahmedabad but I was glad to see hundreds of people waiting for the doors to be opened some hours before. We started the day with hot coffee and cookies. Yes, food first; and it was right after my keynote. I could clearly see that the coffee did some magic right away; the hall was almost full after the coffee break. Jacob Sebastian Presenting at Community Tech Days Jacob Sebastian, an SQL Server MVP and a close friend of mine, had an unusual job of surprising everybody with an innovative topic accompanied with lots of question-and-answer portions. That’s definitely one thing to love Jacob, that is, the novelty of the subject. His presentation was entitled “Best Database Practices for the .Net”; it really created magic on the crowd. Pinal Dave Presenting at Community Tech Days Next to Jacob Sebastian, I presented “Best Database Practices for the SharePoint”. It was really fun to present Database with the perspective of the database itself. The main highlight of my presentation was when I talked about how one can speed up the database performance by 40% for SharePoint in just 40 seconds. It was fun because the most important thing was to convince people to use the recommendation as soon as they walk out of the session. It was really amusing and the response of the participants was remarkable. Pinal Dave Presenting at Community Tech Days My session was followed by the most-awaited session of the day: that of Rushabh Mehta. He is an international BI expert who traveled all the way from Florida to present “Self Service BI” session. This session was funny and truly interesting. In fact, no one knew BI could be this much entertaining and fascinating. Rushabh has an appealing style of presenting the session; he instantly got very much interaction from the audience. Rushabh Mehta Presenting at Community Tech Days We had a networking lunch break in-between, when we talked about many various topics. It is always interesting to get in touch with the Community and feel a part of it. I had a wonderful time during the break. Vinod Kumar Presenting at Community Tech Days After lunch was apparently the most difficult session for the presenter as during this time, many people started to fall sleep and get dizzy. This spot was requested by Microsoft SQL Server Evangelist Vinod Kumar himself. During our discussion he suggested that if he gets this slot he would make sure people are up and more interactive than during the morning session. Just like always, this session was one of the best sessions ever. Vinod is true to his word as he presented the subject of “Time Management for Developer”. This session was the biggest hit in the event because the subject was instilled in the mind of every participant. Vinod Kumar Presenting at Community Tech Days Vinod’s session was followed by his own small session. Due to “insistent public demand”, he presented an interesting subject, “Tricks and Tips of SQL Server“. In 20 minutes he has done another awesome job and all attendees wanted more of the tricks. Just as usual he promised to do that next time for us. Vinod’s session was succeeded by Prabhjot Singh Bakshi’s session. He presented an appealing Silverlight concept. Just the same, he did a great job and people cheered him. Prabhjot Presenting at Community Tech Days We had a special invited speaker, Dhananjay Kumar, traveling all the way from Pune. He always supports our cause to help the Community in empowering participants. He presented the topic about Win7 Mobile and SharePoint integration. This was something many did not even expect to be possible. Kudos to Dhananjay for doing a great job. Dhananjay Kumar Presenting at Community Tech Days All in all, this event was one of the best in the Community Tech Days series in Ahmedabad. We were fortunate that legends from the all over the world were present here to present to the Community. I’d say never underestimate the power of the Community and its influence over the direction of the technology. Vinod Kumar Presenting trophy to Pinal Dave Vinod Kumar Presenting trophy to Pinal Dave This event was a very special gathering to me personally because of your support to the vibrant Community. The following awards were won for last year’s performance: Ahmedabad SQL Server User Group (President: Jacob Sebastian; Leader: Pinal Dave) – Best Tier 2 User Group Best Development Community Individual Contributor – Pinal Dave Speakers I was very glad to receive the award for our entire Community. Attendees at Community Tech Days I want to say thanks to Rushabh Mehta, Vinod Kumar and Dhananjay Kumar for visiting the city and presenting various technology topics in Community Tech Days. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: MVP, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Author Visit, SQLAuthority News, T SQL, Technology

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• Building a database installer with WiX, datadude and Visual Studio 2010

  - by jamiet

  Today I have been using Windows Installer XML (WiX) to build an installer (.msi file) that would install a SQL Server database on a server of my choosing; the source code for that database lives in datadude (a tool which you may know by one of quite a few other names). The basis for this work was a most excellent blog post by Duke Kamstra entitled Implementing a WIX installer that calls the GDR version of VSDBCMD.EXE which coves the delicate intricacies of doing this – particularly how to call Vsdbcmd.exe in a CustomAction. Unfortunately there are a couple of things wrong with Duke’s post: Searching for “datadude wix” didn’t turn it up in the first page of search results and hence it took me a long time to find it. And I knew that it existed. If someone else were after a post on using WiX with datadude its likely that they would never have come across Duke’s post and that would be a great shame because its the definitive post on the matter. It was written in October 2009 and had not been updated for Visual Studio 2010. Well, this blog post is an attempt to solve those problems. Hopefully I’ve solved the first one just by following a few of my blogging SEO tips while writing this blog post, in the rest of it I will explain how I took Duke’s code and updated it to work in Visual Studio 2010. If you need to build a database installer using WiX, datadude and Visual Studio 2010 then you still need to follow Duke’s blog post so go and do that now. Below are the amendments that I made that enabled the project to get built in Visual Studio 2010: In VS2010 datadude’s output files have changed from being called Database.<suffix> to <ProjectName>_Database.<suffix>. Duke’s code was referencing the old file name formats. Duke used $(var.SolutionDir) and relative paths to point to datadude artefacts I have replaced these with Votive Project References http://wix.sourceforge.net/manual-wix3/votive_project_references.htm I commented out all references to MicrosoftSqlTypesDbschema in DatabaseArtifacts.wxi. I don't think this is produced in VS2010 (I may be wrong about that but it wasn't in the output from my project) Similarly I commented out component MicrosoftSqlTypesDbschema in VsdbcmdArtifacts.wxi. It wasn't where Duke's code said it should have been so am assuming/hoping it isn't needed. Duke's ?define block to work out appropriate SrcArchPath actually wasn't working for me (i.e. <?if $(var.Platform)=x64 ?> was evaluating to false)  so I just took out the conditional stuff and declared the path explicitly to the “Program Files (x86)” path. The old code is still there though if you need to put it back. None of the <RegistrySearch> stuff is needed for VS2010 - so I commented it all out! Changed to use /manifest option rather than /model option on vsdbcmd.exe command-line. Personal preference is all! Added a new component in order to bundle along the vsdbcmd.exe.config file Made the install of the Custom Action dependent on the relevant feature being selected for install. This one is actually really important – deselecting the database feature for installation does not, by default, stop the CustomAction from executing and so would cause an error - so that scenario needs to be catered for I have made my amended solution available for download at: http://cid-550f681dad532637.office.live.com/self.aspx/Public/BlogShare/20110210/InstallMyDatabase.zip It contains two projects: the WiX project and the datadude project that is the source to be deployed (for demo purposes it only contains one table). I have also made the .msi available although in order that it gets through file blockers I changed the name from InstallMyDatabase.msi to InstallMyDatabase.ms_ – simply rename the file back once you have downloaded it from: http://cid-550f681dad532637.office.live.com/self.aspx/Public/BlogShare/20110210/InstallMyDatabase.ms%5E_ .You can try it out for yourself – the only thing it does is dump the files into %Program Files%\MyDatabase and uses them to install a database onto a server of your choosing with a name of your choosing - no damaging side-affects. I will caveat this by saying “it works on my machine” and, not having access to a plethora of different machines, I haven’t tested it anywhere else. One potential issue that I know of is that Vsdbcmd.exe has a dependency on SQL Server CE although if you have SQL Server tools or Visual Studio installed you should be fine. Unfortunately its not possible to bundle along the SQL Server CE installer in the .msi because Windows will not allow you to call one installer from inside another – the recommended way to get around this problem is to build a bootstrapper to bundle the whole lot together but doing that is outside the scope of this blog post. If you discover any other issues then please let me know. Here are the screenshots from the installer: And once installed…. Hope this is useful! @jamiet 

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• Design by Contract with Microsoft .Net Code Contract

  - by Fredrik N

  I have done some talks on different events and summits about Defensive Programming and Design by Contract, last time was at Cornerstone’s Developer Summit 2010. Next time will be at SweNug (Sweden .Net User Group). I decided to write a blog post about of some stuffs I was talking about. Users are a terrible thing! Protect your self from them ”Human users have a gift for doing the worst possible thing at the worst possible time.” – Michael T. Nygard, Release It! The kind of users Michael T. Nygard are talking about is the users of a system. We also have users that uses our code, the users I’m going to focus on is the users of our code. Me and you and another developers. “Any fool can write code that a computer can understand. Good programmers write code that humans can understand.” – Martin Fowler Good programmers also writes code that humans know how to use, good programmers also make sure software behave in a predictable manner despise inputs or user actions. Design by Contract   Design by Contract (DbC) is a way for us to make a contract between us (the code writer) and the users of our code. It’s about “If you give me this, I promise to give you this”. It’s not about business validations, that is something completely different that should be part of the domain model. DbC is to make sure the users of our code uses it in a correct way, and that we can rely on the contract and write code in a way where we know that the users will follow the contract. It will make it much easier for us to write code with a contract specified. Something like the following code is something we may see often: public void DoSomething(Object value) { value.DoIKnowThatICanDoThis(); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Where “value” can be uses directly or passed to other methods and later be used. What some of us can easily forget here is that the “value” can be “null”. We will probably not passing a null value, but someone else that uses our code maybe will do it. I think most of you (including me) have passed “null” into a method because you don’t know if the argument need to be specified to a valid value etc. I bet most of you also have got the “Null reference exception”. Sometimes this “Null reference exception” can be hard and take time to fix, because we need to search among our code to see where the “null” value was passed in etc. Wouldn’t it be much better if we can as early as possible specify that the value can’t not be null, so the users of our code also know it when the users starts to use our code, and before run time execution of the code? This is where DbC comes into the picture. We can use DbC to specify what we need, and by doing so we can rely on the contract when we write our code. So the code above can actually use the DoIKnowThatICanDoThis() method on the value object without being worried that the “value” can be null. The contract between the users of the code and us writing the code, says that the “value” can’t be null.   Pre- and Postconditions   When working with DbC we are specifying pre- and postconditions.  Precondition is a condition that should be met before a query or command is executed. An example of a precondition is: “The Value argument of the method can’t be null”, and we make sure the “value” isn’t null before the method is called. Postcondition is a condition that should be met when a command or query is completed, a postcondition will make sure the result is correct. An example of a postconditon is “The method will return a list with at least 1 item”. Commands an Quires When using DbC, we need to know what a Command and a Query is, because some principles that can be good to follow are based on commands and queries. A Command is something that will not return anything, like the SQL’s CREATE, UPDATE and DELETE. There are two kinds of Commands when using DbC, the Creation commands (for example a Constructor), and Others. Others can for example be a Command to add a value to a list, remove or update a value etc. //Creation commands public Stack(int size) //Other commands public void Push(object value); public void Remove(); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   A Query, is something that will return something, for example an Attribute, Property or a Function, like the SQL’s SELECT.   There are two kinds of Queries, the Basic Queries  (Quires that aren’t based on another queries), and the Derived Queries, queries that is based on another queries. Here is an example of queries of a Stack: //Basic Queries public int Count; public object this[int index] { get; } //Derived Queries //Is related to Count Query public bool IsEmpty() { return Count == 0; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } To understand about some principles that are good to follow when using DbC, we need to know about the Commands and different Queries. The 6 Principles When working with DbC, it’s advisable to follow some principles to make it easier to define and use contracts. The following DbC principles are: Separate commands and queries. Separate basic queries from derived queries. For each derived query, write a postcondition that specifies what result will be returned, in terms of one or more basic queries. For each command, write a postcondition that specifies the value of every basic query. For every query and command, decide on a suitable precondition. Write invariants to define unchanging properties of objects. Before I will write about each of them I want you to now that I’m going to use .Net 4.0 Code Contract. I will in the rest of the post uses a simple Stack (Yes I know, .Net already have a Stack class) to give you the basic understanding about using DbC. A Stack is a data structure where the first item in, will be the first item out. Here is a basic implementation of a Stack where not contract is specified yet: public class Stack { private object[] _array; //Basic Queries public uint Count; public object this[uint index] { get { return _array[index]; } set { _array[index] = value; } } //Derived Queries //Is related to Count Query public bool IsEmpty() { return Count == 0; } //Is related to Count and this[] Query public object Top() { return this[Count]; } //Creation commands public Stack(uint size) { Count = 0; _array = new object[size]; } //Other commands public void Push(object value) { this[++Count] = value; } public void Remove() { this[Count] = null; Count--; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Note: The Stack is implemented in a way to demonstrate the use of Code Contract in a simple way, the implementation may not look like how you would implement it, so don’t think this is the perfect Stack implementation, only used for demonstration.   Before I will go deeper into the principles I will simply mention how we can use the .Net Code Contract. I mention before about pre- and postcondition, is about “Require” something and to “Ensure” something. When using Code Contract, we will use a static class called “Contract” and is located in he “System.Diagnostics.Contracts” namespace. The contract must be specified at the top or our member statement block. To specify a precondition with Code Contract we uses the Contract.Requires method, and to specify a postcondition, we uses the Contract.Ensure method. Here is an example where both a pre- and postcondition are used: public object Top() { Contract.Requires(Count > 0, "Stack is empty"); Contract.Ensures(Contract.Result<object>() == this[Count]); return this[Count]; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   The contract above requires that the Count is greater than 0, if not we can’t get the item at the Top of a Stack. We also Ensures that the results (By using the Contract.Result method, we can specify a postcondition that will check if the value returned from a method is correct) of the Top query is equal to this[Count].   1. Separate Commands and Queries   When working with DbC, it’s important to separate Command and Quires. A method should either be a command that performs an Action, or returning information to the caller, not both. By asking a question the answer shouldn’t be changed. The following is an example of a Command and a Query of a Stack: public void Push(object value) public object Top() .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   The Push is a command and will not return anything, just add a value to the Stack, the Top is a query to get the item at the top of the stack.   2. Separate basic queries from derived queries There are two different kinds of queries,  the basic queries that doesn’t rely on another queries, and derived queries that uses a basic query. The “Separate basic queries from derived queries” principle is about about that derived queries can be specified in terms of basic queries. So this principles is more about recognizing that a query is a derived query or a basic query. It will then make is much easier to follow the other principles. The following code shows a basic query and a derived query: //Basic Queries public uint Count; //Derived Queries //Is related to Count Query public bool IsEmpty() { return Count == 0; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   We can see that IsEmpty will use the Count query, and that makes the IsEmpty a Derived query.   3. For each derived query, write a postcondition that specifies what result will be returned, in terms of one or more basic queries.   When the derived query is recognize we can follow the 3ed principle. For each derived query, we can create a postcondition that specifies what result our derived query will return in terms of one or more basic queries. Remember that DbC is about contracts between the users of the code and us writing the code. So we can’t use demand that the users will pass in a valid value, we must also ensure that we will give the users what the users wants, when the user is following our contract. The IsEmpty query of the Stack will use a Count query and that will make the IsEmpty a Derived query, so we should now write a postcondition that specified what results will be returned, in terms of using a basic query and in this case the Count query, //Basic Queries public uint Count; //Derived Queries public bool IsEmpty() { Contract.Ensures(Contract.Result<bool>() == (Count == 0)); return Count == 0; } The Contract.Ensures is used to create a postcondition. The above code will make sure that the results of the IsEmpty (by using the Contract.Result to get the result of the IsEmpty method) is correct, that will say that the IsEmpty will be either true or false based on Count is equal to 0 or not. The postcondition are using a basic query, so the IsEmpty is now following the 3ed principle. We also have another Derived Query, the Top query, it will also need a postcondition and it uses all basic queries. The Result of the Top method must be the same value as the this[] query returns. //Basic Queries public uint Count; public object this[uint index] { get { return _array[index]; } set { _array[index] = value; } } //Derived Queries //Is related to Count and this[] Query public object Top() { Contract.Ensures(Contract.Result<object>() == this[Count]); return this[Count]; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   4. For each command, write a postcondition that specifies the value of every basic query.   For each command we will create a postconditon that specifies the value of basic queries. If we look at the Stack implementation we will have three Commands, one Creation command, the Constructor, and two others commands, Push and Remove. Those commands need a postcondition and they should include basic query to follow the 4th principle. //Creation commands public Stack(uint size) { Contract.Ensures(Count == 0); Count = 0; _array = new object[size]; } //Other commands public void Push(object value) { Contract.Ensures(Count == Contract.OldValue<uint>(Count) + 1); Contract.Ensures(this[Count] == value); this[++Count] = value; } public void Remove() { Contract.Ensures(Count == Contract.OldValue<uint>(Count) - 1); this[Count] = null; Count--; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   As you can see the Create command will Ensures that Count will be 0 when the Stack is created, when a Stack is created there shouldn’t be any items in the stack. The Push command will take a value and put it into the Stack, when an item is pushed into the Stack, the Count need to be increased to know the number of items added to the Stack, and we must also make sure the item is really added to the Stack. The postconditon of the Push method will make sure the that old value of the Count (by using the Contract.OldValue we can get the value a Query has before the method is called)  plus 1 will be equal to the Count query, this is the way we can ensure that the Push will increase the Count with one. We also make sure the this[] query will now contain the item we pushed into the Stack. The Remove method must make sure the Count is decreased by one when the top item is removed from the Stack. The Commands is now following the 4th principle, where each command now have a postcondition that used the value of basic queries. Note: The principle says every basic Query, the Remove only used one Query the Count, it’s because this command can’t use the this[] query because an item is removed, so the only way to make sure an item is removed is to just use the Count query, so the Remove will still follow the principle.   5. For every query and command, decide on a suitable precondition.   We have now focused only on postcondition, now time for some preconditons. The 5th principle is about deciding a suitable preconditon for every query and command. If we starts to look at one of our basic queries (will not go through all Queries and commands here, just some of them) the this[] query, we can’t pass an index that is lower then 1 (.Net arrays and list are zero based, but not the stack in this blog post ;)) and the index can’t be lesser than the number of items in the stack. So here we will need a preconditon. public object this[uint index] { get { Contract.Requires(index >= 1); Contract.Requires(index <= Count); return _array[index]; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Think about the Contract as an documentation about how to use the code in a correct way, so if the contract could be specified elsewhere (not part of the method body), we could simply write “return _array[index]” and there is no need to check if index is greater or lesser than Count, because that is specified in a “contract”. The implementation of Code Contract, requires that the contract is specified in the code. As a developer I would rather have this contract elsewhere (Like Spec#) or implemented in a way Eiffel uses it as part of the language. Now when we have looked at one Query, we can also look at one command, the Remove command (You can see the whole implementation of the Stack at the end of this blog post, where precondition is added to more queries and commands then what I’m going to show in this section). We can only Remove an item if the Count is greater than 0. So we can write a precondition that will require that Count must be greater than 0. public void Remove() { Contract.Requires(Count > 0); Contract.Ensures(Count == Contract.OldValue<uint>(Count) - 1); this[Count] = null; Count--; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   6. Write invariants to define unchanging properties of objects.   The last principle is about making sure the object are feeling great! This is done by using invariants. When using Code Contract we can specify invariants by adding a method with the attribute ContractInvariantMethod, the method must be private or public and can only contains calls to Contract.Invariant. To make sure the Stack feels great, the Stack must have 0 or more items, the Count can’t never be a negative value to make sure each command and queries can be used of the Stack. Here is our invariant for the Stack object: [ContractInvariantMethod] private void ObjectInvariant() { Contract.Invariant(Count >= 0); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Note: The ObjectInvariant method will be called every time after a Query or Commands is called. Here is the full example using Code Contract:   public class Stack { private object[] _array; //Basic Queries public uint Count; public object this[uint index] { get { Contract.Requires(index >= 1); Contract.Requires(index <= Count); return _array[index]; } set { Contract.Requires(index >= 1); Contract.Requires(index <= Count); _array[index] = value; } } //Derived Queries //Is related to Count Query public bool IsEmpty() { Contract.Ensures(Contract.Result<bool>() == (Count == 0)); return Count == 0; } //Is related to Count and this[] Query public object Top() { Contract.Requires(Count > 0, "Stack is empty"); Contract.Ensures(Contract.Result<object>() == this[Count]); return this[Count]; } //Creation commands public Stack(uint size) { Contract.Requires(size > 0); Contract.Ensures(Count == 0); Count = 0; _array = new object[size]; } //Other commands public void Push(object value) { Contract.Requires(value != null); Contract.Ensures(Count == Contract.OldValue<uint>(Count) + 1); Contract.Ensures(this[Count] == value); this[++Count] = value; } public void Remove() { Contract.Requires(Count > 0); Contract.Ensures(Count == Contract.OldValue<uint>(Count) - 1); this[Count] = null; Count--; } [ContractInvariantMethod] private void ObjectInvariant() { Contract.Invariant(Count >= 0); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Summary By using Design By Contract we can make sure the users are using our code in a correct way, and we must also make sure the users will get the expected results when they uses our code. This can be done by specifying contracts. To make it easy to use Design By Contract, some principles may be good to follow like the separation of commands an queries. With .Net 4.0 we can use the Code Contract feature to specify contracts.

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• IIS Permissions or NTFS Permissions?

  - by Jason

  I currently have a Windows Server 2003 setup to serve multiple sites via IIS. One of our directories needs to allow access to only 1 specific AD Security Group. I know there are two ways to accomplish this. One is using IIS to add permissions and the other is to set permissions on the folder/directory itself. A script runs at night and populates the content so users only need read permissions to view it in a browser. My question is which one is preferred?

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• Connecting to DB2 from SSIS

  - by Christopher House

  The project I'm currently working on involves moving various pieces of data from a legacy DB2 environment to some SQL Server and flat file locations.  Most of the data flows are real time, so they were a natural fit for the client's MQSeries on their iSeries servers and BizTalk to handle the messaging.  Some of the data flows, however, are daily batch type transmissions.  For the daily batch transmissions, it was decided that we'd use SSIS to pull the data direct from DB2 to either a SQL Server or flat file.  I'm not at all an SSIS guy, I've done a bit here and there, but mainly for situations were we needed to move data from a dev environment to QA, mostly informal stuff like that.  And, as much as I'm not an SSIS guy, I'm even less a DB2/iSeries guy.  Prior to this engagement, my knowledge of DB2 was limited to the fact that it's an IBM product and that it was probably a DBMS flatform (that's what the DB in DB2 means, right?).   One of my first goals when I came onto this project was to develop of POC SSIS package to pull some data from DB2 and dump it to a flat file.  It sounded like a pretty straight forward task.  As always, the devil is in the details.  Configuring the DB2 connection manager took a bit of trial and error.  As such, I thought I'd post my experiences here in hopes that they might save someone the efforts I went through.  That being said, please keep in mind, as I pointed out, I'm not at all a DB2 guy, so my terminology and explanations may not be 100% spot on. Before you get started, you need to figure out how you're going to connect to DB2.  From the research I did, it looks like there are a few options.  IBM has both an OLE DB and .Net data provider which can be found here.  I installed their client access tools and tried to use both the .Net and OLE DB providers but I received an error message from both when attempting to connect to the iSeries that indicated I needed a license for a product called DB2 Connect.  I inquired with one of my client's iSeries resources about a license for this product and it appears they didn't have one, so that meant the IBM drivers were out.  The other option that I found quite a bit of discussion around was Microsoft's OLE DB Provider for DB2.  This driver is part of the feature pack for SQL Server 2008 Enterprise Edition and can be downloaded here. As it turns out, I already had Microsoft's driver installed on my dev VM, which stuck me as odd since I hadn't installed it.  I discovered that the driver is installed with the BizTalk adapter pack for host systems, which was also installed on my VM.  However, it looks like the version used by the adapter pack is newer than the version provided in the SQL Server feature pack.   Once you get the driver installed, create a connection manager in your package just like you normally would and select the Microsoft OLE DB Provider for DB2 from the list of available drivers. After you select the driver, you'll need to enter in your host name, login credentials and initial catalog. A couple of things to note here.  First, the Initial catalog needs to be the same as your host name.  Not sure why that is, but trust me, it just does.  Second, for credentials, in my environment, we're using what the client's iSeries people refer to as "profiles".  I guess this is similar to SQL auth in the SQL Server world.  In other words, they've given me a username and password for connecting to DB, so I've entered it here. Next, click the Data Links button.  On the Data Links screen, enter your package collection on the first tab. Package collection is one of those DB2 concepts I'm still trying to figure out.  From the little bit I've read, packages are used to control SQL compilation and each DB2 connection needs one.  The package collection, I believe, controls where your package is created.  One of the iSeries folks I've been working with told me that I should always use QGPL for my package collection, as QGPL is "general purpose" and doesn't require any additional authority. Next click the ellipsis next to the Network drop-down.  Here you'll want to enter your host name again. Again, not sure why you need to do this, but trust me, my connection wouldn't work until I entered my hostname here. Finally, go to the Advanced tab, select your DBMS platform and check Process binary as character. My environment is DB2 on the iSeries and iSeries is the replacement for AS/400, so I selected DB2/AS400 for my platform.  Process binary as character was necessary to handle some of the DB2 data types.  I had a few columns that showed all their data as "System.Byte[]".  Checking Process binary as character resolved this. At this point, you should be good to go.  You can go back to the Connection tab on the Data Links dialog to perform a couple of tests to validate your configuration.  The Test Connection button is obvious, this just verifies you can connect to the host using the configuration data you've entered.  The Packages button will attempt to connect to the host and create the packages required to execute queries. This isn't meant to be a comprehensive look SSIS and DB2, these are just some of the notes I've come up with since I've started working with DB2 and SSIS.  I'm sure as I continue developing my packages, I'll find more quirks and will post them here.

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• SQLAuthority News – Don’t Be Afraid To Fool The World – Video by John Sonmez

  - by Pinal Dave

  Sometime some words and statements grabs your attention and it is hard to stop thinking about that after a while. Something similar happened a few days ago when I read the twitter statement of my friend and Pluralsight author John Sonmez. He twitted few days ago very interesting statement. “I don’t know a single successful person, who doesn’t deep down think that have the world fooled. #fooltheworld” by John Sonmez. When I read it, I was extremely intrigued by this statement. I read it many times, I shared with my family and I just could not stop interpreting this statement. It was indeed fun to read it again and again and there are so many different meanings one can take away from the statement. I know John very well, he is a  wonderful person and have very positive energy for the life. I just had to request him to build a video around it. Right after 5 days of my request, John created a wonderful video around this subject. I watched it multiple times as it was a wonderful video. I am not going to write about what was in the video much as I suggest you to watch the video itself. Here is one of the personal stories I want to share which is absolutely relevant to this video. I think my story 100% resonant the story of John. A Real Story from My Past Three years ago, I submitted a session in one of the SharePoint conference as a SQL Server session. My session was accepted and I prepared it very well. I put more than 2 month’s time to prepare for the session and I was very excited to present the session. I reached to the event place traveling thousands of the miles and I was very much excited to present the session. However, there was a little mixed up in the session. There were multiple session which were similar to my session title. One of the other speakers also had proposed a database related session and was selected. When the material went to print the printing team got confused and by mistake swapped the sessions. The other speaker got Performance with SQL Server session and I had received Performance with SharePoint session. IT was indeed a big mixed up but now that is how it was in the event guide and it was marketed the same way everything in the event. A Big Mix Up I had to talk with the event organizer and we come to the conclusion that we all had good intention but things just got mixed up and now was the time when “The show must go on“. I had a great amount of hesitation to go and present the session as I had personally never worked with Sharepoint so close in my life and my session abstracted talked about SharePoint tricks in depth. Two hours before the session I took the help of one of my friend and installed the SharePoint on my box. He showed me a few things here and there but it was never a good enough time to learn everything which I wanted to learn. The Moments of Confidence I was very scared and nervous to go on the stage as a SharePoint was not something I felt comfortable. However, I decided to go on stage with confidence as a SharePoint expert. Though I did not know SharePoint at the best, I had confidence that whatever I know is correct and I will not misguide people. I had no intention to fool people but I had no intention to accept that I am a fool and you all wasted your time and money to dedicate your time to attend my session. I decided to be honest but at the same time decided to take the session beyond my expertise. The sixty minutes of the session went very fine and I was able to manage all the difficult question at a satisfactory level. When the session was over my feeling was that I would have not presented or talked any different if I had more knowledge of the SharePoint at that time. I think it was one of my best sessions and it was reflected in the session feedback as well. I was the best speaker across all the track and my session had highest ranking. I was delighted and I learned a very valuable lesson. I must go beyond my limits and knowledge. I must aim higher and work harder. I should not lie but I should have confidence that I have a good heart and I put 100% in my efforts.  Lessions Learned Since this incident I have learned a lot about SharePoint and I am now a regular speaker at various SharePoint conferences along with SQL Server sessions. I am motivated and I am not afraid. I know people have lots of expectation from me but I have learned not to judge myself before I do my best. I leave the judgement of my efforts to my audience. I do not take the burden of the feedback on me, even though I know my audience have expected from me. I know what I know and I put my best. I must go out, if I fail, I learn from my mistake but I must keep my progress trajectory very high. As John said in the video, sometime success is not something we can achieve 100% but we can keep on going near to it. As long as we do not lose our focus from our goal and do not deviate from our progress path, we are doing things right. Reference: Pinal Dave (http://blog.sqlauthority.com)  Filed under: About Me, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Scrum in 5 Minutes

  - by Stephen.Walther

  The goal of this blog entry is to explain the basic concepts of Scrum in less than five minutes. You learn how Scrum can help a team of developers to successfully complete a complex software project. Product Backlog and the Product Owner Imagine that you are part of a team which needs to create a new website – for example, an e-commerce website. You have an overwhelming amount of work to do. You need to build (or possibly buy) a shopping cart, install an SSL certificate, create a product catalog, create a Facebook page, and at least a hundred other things that you have not thought of yet. According to Scrum, the first thing you should do is create a list. Place the highest priority items at the top of the list and the lower priority items lower in the list. For example, creating the shopping cart and buying the domain name might be high priority items and creating a Facebook page might be a lower priority item. In Scrum, this list is called the Product Backlog. How do you prioritize the items in the Product Backlog? Different stakeholders in the project might have different priorities. Gary, your division VP, thinks that it is crucial that the e-commerce site has a mobile app. Sally, your direct manager, thinks taking advantage of new HTML5 features is much more important. Multiple people are pulling you in different directions. According to Scrum, it is important that you always designate one person, and only one person, as the Product Owner. The Product Owner is the person who decides what items should be added to the Product Backlog and the priority of the items in the Product Backlog. The Product Owner could be the customer who is paying the bills, the project manager who is responsible for delivering the project, or a customer representative. The critical point is that the Product Owner must always be a single person and that single person has absolute authority over the Product Backlog. Sprints and the Sprint Backlog So now the developer team has a prioritized list of items and they can start work. The team starts implementing the first item in the Backlog — the shopping cart — and the team is making good progress. Unfortunately, however, half-way through the work of implementing the shopping cart, the Product Owner changes his mind. The Product Owner decides that it is much more important to create the product catalog before the shopping cart. With some frustration, the team switches their developmental efforts to focus on implementing the product catalog. However, part way through completing this work, once again the Product Owner changes his mind about the highest priority item. Getting work done when priorities are constantly shifting is frustrating for the developer team and it results in lower productivity. At the same time, however, the Product Owner needs to have absolute authority over the priority of the items which need to get done. Scrum solves this conflict with the concept of Sprints. In Scrum, a developer team works in Sprints. At the beginning of a Sprint the developers and the Product Owner agree on the items from the backlog which they will complete during the Sprint. This subset of items from the Product Backlog becomes the Sprint Backlog. During the Sprint, the Product Owner is not allowed to change the items in the Sprint Backlog. In other words, the Product Owner cannot shift priorities on the developer team during the Sprint. Different teams use Sprints of different lengths such as one month Sprints, two-week Sprints, and one week Sprints. For high-stress, time critical projects, teams typically choose shorter sprints such as one week sprints. For more mature projects, longer one month sprints might be more appropriate. A team can pick whatever Sprint length makes sense for them just as long as the team is consistent. You should pick a Sprint length and stick with it. Daily Scrum During a Sprint, the developer team needs to have meetings to coordinate their work on completing the items in the Sprint Backlog. For example, the team needs to discuss who is working on what and whether any blocking issues have been discovered. Developers hate meetings (well, sane developers hate meetings). Meetings take developers away from their work of actually implementing stuff as opposed to talking about implementing stuff. However, a developer team which never has meetings and never coordinates their work also has problems. For example, Fred might get stuck on a programming problem for days and never reach out for help even though Tom (who sits in the cubicle next to him) has already solved the very same problem. Or, both Ted and Fred might have started working on the same item from the Sprint Backlog at the same time. In Scrum, these conflicting needs – limiting meetings but enabling team coordination – are resolved with the idea of the Daily Scrum. The Daily Scrum is a meeting for coordinating the work of the developer team which happens once a day. To keep the meeting short, each developer answers only the following three questions: 1. What have you done since yesterday? 2. What do you plan to do today? 3. Any impediments in your way? During the Daily Scrum, developers are not allowed to talk about issues with their cat, do demos of their latest work, or tell heroic stories of programming problems overcome. The meeting must be kept short — typically about 15 minutes. Issues which come up during the Daily Scrum should be discussed in separate meetings which do not involve the whole developer team. Stories and Tasks Items in the Product or Sprint Backlog – such as building a shopping cart or creating a Facebook page – are often referred to as User Stories or Stories. The Stories are created by the Product Owner and should represent some business need. Unlike the Product Owner, the developer team needs to think about how a Story should be implemented. At the beginning of a Sprint, the developer team takes the Stories from the Sprint Backlog and breaks the stories into tasks. For example, the developer team might take the Create a Shopping Cart story and break it into the following tasks: · Enable users to add and remote items from shopping cart · Persist the shopping cart to database between visits · Redirect user to checkout page when Checkout button is clicked During the Daily Scrum, members of the developer team volunteer to complete the tasks required to implement the next Story in the Sprint Backlog. When a developer talks about what he did yesterday or plans to do tomorrow then the developer should be referring to a task. Stories are owned by the Product Owner and a story is all about business value. In contrast, the tasks are owned by the developer team and a task is all about implementation details. A story might take several days or weeks to complete. A task is something which a developer can complete in less than a day. Some teams get lazy about breaking stories into tasks. Neglecting to break stories into tasks can lead to “Never Ending Stories” If you don’t break a story into tasks, then you can’t know how much of a story has actually been completed because you don’t have a clear idea about the implementation steps required to complete the story. Scrumboard During the Daily Scrum, the developer team uses a Scrumboard to coordinate their work. A Scrumboard contains a list of the stories for the current Sprint, the tasks associated with each Story, and the state of each task. The developer team uses the Scrumboard so everyone on the team can see, at a glance, what everyone is working on. As a developer works on a task, the task moves from state to state and the state of the task is updated on the Scrumboard. Common task states are ToDo, In Progress, and Done. Some teams include additional task states such as Needs Review or Needs Testing. Some teams use a physical Scrumboard. In that case, you use index cards to represent the stories and the tasks and you tack the index cards onto a physical board. Using a physical Scrumboard has several disadvantages. A physical Scrumboard does not work well with a distributed team – for example, it is hard to share the same physical Scrumboard between Boston and Seattle. Also, generating reports from a physical Scrumboard is more difficult than generating reports from an online Scrumboard. Estimating Stories and Tasks Stakeholders in a project, the people investing in a project, need to have an idea of how a project is progressing and when the project will be completed. For example, if you are investing in creating an e-commerce site, you need to know when the site can be launched. It is not enough to just say that “the project will be done when it is done” because the stakeholders almost certainly have a limited budget to devote to the project. The people investing in the project cannot determine the business value of the project unless they can have an estimate of how long it will take to complete the project. Developers hate to give estimates. The reason that developers hate to give estimates is that the estimates are almost always completely made up. For example, you really don’t know how long it takes to build a shopping cart until you finish building a shopping cart, and at that point, the estimate is no longer useful. The problem is that writing code is much more like Finding a Cure for Cancer than Building a Brick Wall. Building a brick wall is very straightforward. After you learn how to add one brick to a wall, you understand everything that is involved in adding a brick to a wall. There is no additional research required and no surprises. If, on the other hand, I assembled a team of scientists and asked them to find a cure for cancer, and estimate exactly how long it will take, they would have no idea. The problem is that there are too many unknowns. I don’t know how to cure cancer, I need to do a lot of research here, so I cannot even begin to estimate how long it will take. So developers hate to provide estimates, but the Product Owner and other product stakeholders, have a legitimate need for estimates. Scrum resolves this conflict by using the idea of Story Points. Different teams use different units to represent Story Points. For example, some teams use shirt sizes such as Small, Medium, Large, and X-Large. Some teams prefer to use Coffee Cup sizes such as Tall, Short, and Grande. Finally, some teams like to use numbers from the Fibonacci series. These alternative units are converted into a Story Point value. Regardless of the type of unit which you use to represent Story Points, the goal is the same. Instead of attempting to estimate a Story in hours (which is doomed to failure), you use a much less fine-grained measure of work. A developer team is much more likely to be able to estimate that a Story is Small or X-Large than the exact number of hours required to complete the story. So you can think of Story Points as a compromise between the needs of the Product Owner and the developer team. When a Sprint starts, the developer team devotes more time to thinking about the Stories in a Sprint and the developer team breaks the Stories into Tasks. In Scrum, you estimate the work required to complete a Story by using Story Points and you estimate the work required to complete a task by using hours. The difference between Stories and Tasks is that you don’t create a task until you are just about ready to start working on a task. A task is something that you should be able to create within a day, so you have a much better chance of providing an accurate estimate of the work required to complete a task than a story. Burndown Charts In Scrum, you use Burndown charts to represent the remaining work on a project. You use Release Burndown charts to represent the overall remaining work for a project and you use Sprint Burndown charts to represent the overall remaining work for a particular Sprint. You create a Release Burndown chart by calculating the remaining number of uncompleted Story Points for the entire Product Backlog every day. The vertical axis represents Story Points and the horizontal axis represents time. A Sprint Burndown chart is similar to a Release Burndown chart, but it focuses on the remaining work for a particular Sprint. There are two different types of Sprint Burndown charts. You can either represent the remaining work in a Sprint with Story Points or with task hours (the following image, taken from Wikipedia, uses hours). When each Product Backlog Story is completed, the Release Burndown chart slopes down. When each Story or task is completed, the Sprint Burndown chart slopes down. Burndown charts typically do not always slope down over time. As new work is added to the Product Backlog, the Release Burndown chart slopes up. If new tasks are discovered during a Sprint, the Sprint Burndown chart will also slope up. The purpose of a Burndown chart is to give you a way to track team progress over time. If, halfway through a Sprint, the Sprint Burndown chart is still climbing a hill then you know that you are in trouble. Team Velocity Stakeholders in a project always want more work done faster. For example, the Product Owner for the e-commerce site wants the website to launch before tomorrow. Developers tend to be overly optimistic. Rarely do developers acknowledge the physical limitations of reality. So Project stakeholders and the developer team often collude to delude themselves about how much work can be done and how quickly. Too many software projects begin in a state of optimism and end in frustration as deadlines zoom by. In Scrum, this problem is overcome by calculating a number called the Team Velocity. The Team Velocity is a measure of the average number of Story Points which a team has completed in previous Sprints. Knowing the Team Velocity is important during the Sprint Planning meeting when the Product Owner and the developer team work together to determine the number of stories which can be completed in the next Sprint. If you know the Team Velocity then you can avoid committing to do more work than the team has been able to accomplish in the past, and your team is much more likely to complete all of the work required for the next Sprint. Scrum Master There are three roles in Scrum: the Product Owner, the developer team, and the Scrum Master. I’v e already discussed the Product Owner. The Product Owner is the one and only person who maintains the Product Backlog and prioritizes the stories. I’ve also described the role of the developer team. The members of the developer team do the work of implementing the stories by breaking the stories into tasks. The final role, which I have not discussed, is the role of the Scrum Master. The Scrum Master is responsible for ensuring that the team is following the Scrum process. For example, the Scrum Master is responsible for making sure that there is a Daily Scrum meeting and that everyone answers the standard three questions. The Scrum Master is also responsible for removing (non-technical) impediments which the team might encounter. For example, if the team cannot start work until everyone installs the latest version of Microsoft Visual Studio then the Scrum Master has the responsibility of working with management to get the latest version of Visual Studio as quickly as possible. The Scrum Master can be a member of the developer team. Furthermore, different people can take on the role of the Scrum Master over time. The Scrum Master, however, cannot be the same person as the Product Owner. Using SonicAgile SonicAgile (SonicAgile.com) is an online tool which you can use to manage your projects using Scrum. You can use the SonicAgile Product Backlog to create a prioritized list of stories. You can estimate the size of the Stories using different Story Point units such as Shirt Sizes and Coffee Cup sizes. You can use SonicAgile during the Sprint Planning meeting to select the Stories that you want to complete during a particular Sprint. You can configure Sprints to be any length of time. SonicAgile calculates Team Velocity automatically and displays a warning when you add too many stories to a Sprint. In other words, it warns you when it thinks you are overcommitting in a Sprint. SonicAgile also includes a Scrumboard which displays the list of Stories selected for a Sprint and the tasks associated with each story. You can drag tasks from one task state to another. Finally, SonicAgile enables you to generate Release Burndown and Sprint Burndown charts. You can use these charts to view the progress of your team. To learn more about SonicAgile, visit SonicAgile.com. Summary In this post, I described many of the basic concepts of Scrum. You learned how a Product Owner uses a Product Backlog to create a prioritized list of tasks. I explained why work is completed in Sprints so the developer team can be more productive. I also explained how a developer team uses the daily scrum to coordinate their work. You learned how the developer team uses a Scrumboard to see, at a glance, who is working on what and the state of each task. I also discussed Burndown charts. You learned how you can use both Release and Sprint Burndown charts to track team progress in completing a project. Finally, I described the crucial role of the Scrum Master – the person who is responsible for ensuring that the rules of Scrum are being followed. My goal was not to describe all of the concepts of Scrum. This post was intended to be an introductory overview. For a comprehensive explanation of Scrum, I recommend reading Ken Schwaber’s book Agile Project Management with Scrum: http://www.amazon.com/Agile-Project-Management-Microsoft-Professional/dp/073561993X/ref=la_B001H6ODMC_1_1?ie=UTF8&qid=1345224000&sr=1-1

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• Setting up a local AI server - easy with Solaris 11

  - by Stefan Hinker

  Many things are new in Solaris 11, Autoinstall is one of them.  If, like me, you've known Jumpstart for the last 2 centuries or so, you'll have to start from scratch.  Well, almost, as the concepts are similar, and it's not all that difficult.  Just new. I wanted to have an AI server that I could use for demo purposes, on the train if need be.  That answers the question of hardware requirements: portable.  But let's start at the beginning. First, you need an OS image, of course.  In the new world of Solaris 11, it is now called a repository.  The original can be downloaded from the Solaris 11 page at Oracle.   What you want is the "Oracle Solaris 11 11/11 Repository Image", which comes in two parts that can be combined using cat.  MD5 checksums for these (and all other downloads from that page) are available closer to the top of the page. With that, building the repository is quick and simple: # zfs create -o mountpoint=/export/repo rpool/ai/repo # zfs create rpool/ai/repo/s11 # mount -o ro -F hsfs /tmp/sol-11-1111-repo-full.iso /mnt # rsync -aP /mnt/repo /export/repo/s11 # umount /mnt # pkgrepo rebuild -s /export/repo/sol11/repo # zfs snapshot rpool/ai/repo/sol11@fcs # pkgrepo info -s /export/repo/sol11/repo PUBLISHER PACKAGES STATUS UPDATED solaris 4292 online 2012-03-12T20:47:15.378639Z That's all there's to it.  Let's make a snapshot, just to be on the safe side.  You never know when one will come in handy.  To use this repository, you could just add it as a file-based publisher: # pkg set-publisher -g file:///export/repo/sol11/repo solaris In case I'd want to access this repository through a (virtual) network, i'll now quickly activate the repository-service: # svccfg -s application/pkg/server \ setprop pkg/inst_root=/export/repo/sol11/repo # svccfg -s application/pkg/server setprop pkg/readonly=true # svcadm refresh application/pkg/server # svcadm enable application/pkg/server That's all you need - now point your browser to http://localhost/ to view your beautiful repository-server. Step 1 is done.  All of this, by the way, is nicely documented in the README file that's contained in the repository image. Of course, we already have updates to the original release.  You can find them in MOS in the Oracle Solaris 11 Support Repository Updates (SRU) Index.  You can simply add these to your existing repository or create separate repositories for each SRU.  The individual SRUs are self-sufficient and incremental - SRU4 includes all updates from SRU2 and SRU3.  With ZFS, you can also get both: A full repository with all updates and at the same time incremental ones up to each of the updates: # mount -o ro -F hsfs /tmp/sol-11-1111-sru4-05-incr-repo.iso /mnt # pkgrecv -s /mnt/repo -d /export/repo/sol11/repo '*' # umount /mnt # pkgrepo rebuild -s /export/repo/sol11/repo # zfs snapshot rpool/ai/repo/sol11@sru4 # zfs set snapdir=visible rpool/ai/repo/sol11 # svcadm restart svc:/application/pkg/server:default The normal repository is now updated to SRU4.  Thanks to the ZFS snapshots, there is also a valid repository of Solaris 11 11/11 without the update located at /export/repo/sol11/.zfs/snapshot/fcs . If you like, you can also create another repository service for each update, running on a separate port. But now lets continue with the AI server.  Just a little bit of reading in the dokumentation makes it clear that we will need to run a DHCP server for this.  Since I already have one active (for my SunRay installation) and since it's a good idea to have these kinds of services separate anyway, I decided to create this in a Zone.  So, let's create one first: # zfs create -o mountpoint=/export/install rpool/ai/install # zfs create -o mountpoint=/zones rpool/zones # zonecfg -z ai-server zonecfg:ai-server> create create: Using system default template 'SYSdefault' zonecfg:ai-server> set zonepath=/zones/ai-server zonecfg:ai-server> add dataset zonecfg:ai-server:dataset> set name=rpool/ai/install zonecfg:ai-server:dataset> set alias=install zonecfg:ai-server:dataset> end zonecfg:ai-server> commit zonecfg:ai-server> exit # zoneadm -z ai-server install # zoneadm -z ai-server boot ; zlogin -C ai-server Give it a hostname and IP address at first boot, and there's the Zone.  For a publisher for Solaris packages, it will be bound to the "System Publisher" from the Global Zone.  The /export/install filesystem, of course, is intended to be used by the AI server.  Let's configure it now: #zlogin ai-server root@ai-server:~# pkg install install/installadm root@ai-server:~# installadm create-service -n x86-fcs -a i386 \ -s pkg://solaris/install-image/[email protected],5.11-0.175.0.0.0.2.1482 \ -d /export/install/fcs -i 192.168.2.20 -c 3 With that, the core AI server is already done.  What happened here?  First, I installed the AI server software.  IPS makes that nice and easy.  If necessary, it'll also pull in the required DHCP-Server and anything else that might be missing.  Watch out for that DHCP server software.  In Solaris 11, there are two different versions.  There's the one you might know from Solaris 10 and earlier, and then there's a new one from ISC.  The latter is the one we need for AI.  The SMF service names of both are very similar.  The "old" one is "svc:/network/dhcp-server:default". The ISC-server comes with several SMF-services. We at least need "svc:/network/dhcp/server:ipv4".  The command "installadm create-service" creates the installation-service. It's called "x86-fcs", serves the "i386" architecture and gets its boot image from the repository of the system publisher, using version 5.11,5.11-0.175.0.0.0.2.1482, which is Solaris 11 11/11.  (The option "-a i386" in this example is optional, since the installserver itself runs on a x86 machine.) The boot-environment for clients is created in /export/install/fcs and the DHCP-server is configured for 3 IP-addresses starting at 192.168.2.20.  This configuration is stored in a very human readable form in /etc/inet/dhcpd4.conf.  An AI-service for SPARC systems could be created in the very same way, using "-a sparc" as the architecture option. Now we would be ready to register and install the first client.  It would be installed with the default "solaris-large-server" using the publisher "http://pkg.oracle.com/solaris/release" and would query it's configuration interactively at first boot.  This makes it very clear that an AI-server is really only a boot-server.  The true source of packets to install can be different.  Since I don't like these defaults for my demo setup, I did some extra config work for my clients. The configuration of a client is controlled by manifests and profiles.  The manifest controls which packets are installed and how the filesystems are layed out.  In that, it's very much like the old "rules.ok" file in Jumpstart.  Profiles contain additional configuration like root passwords, primary user account, IP addresses, keyboard layout etc.  Hence, profiles are very similar to the old sysid.cfg file. The easiest way to get your hands on a manifest is to ask the AI server we just created to give us it's default one.  Then modify that to our liking and give it back to the installserver to use: root@ai-server:~# mkdir -p /export/install/configs/manifests root@ai-server:~# cd /export/install/configs/manifests root@ai-server:~# installadm export -n x86-fcs -m orig_default \ -o orig_default.xml root@ai-server:~# cp orig_default.xml s11-fcs.small.local.xml root@ai-server:~# vi s11-fcs.small.local.xml root@ai-server:~# more s11-fcs.small.local.xml <!DOCTYPE auto_install SYSTEM "file:///usr/share/install/ai.dtd.1"> <auto_install> <ai_instance name="S11 Small fcs local"> <target> <logical> <zpool name="rpool" is_root="true"> <filesystem name="export" mountpoint="/export"/> <filesystem name="export/home"/> <be name="solaris"/> </zpool> </logical> </target> <software type="IPS"> <destination> <image> <!-- Specify locales to install --> <facet set="false">facet.locale.*</facet> <facet set="true">facet.locale.de</facet> <facet set="true">facet.locale.de_DE</facet> <facet set="true">facet.locale.en</facet> <facet set="true">facet.locale.en_US</facet> </image> </destination> <source> <publisher name="solaris"> <origin name="http://192.168.2.12/"/> </publisher> </source> <!-- By default the latest build available, in the specified IPS repository, is installed. If another build is required, the build number has to be appended to the 'entire' package in the following form: <name>pkg:/[email protected]#</name> --> <software_data action="install"> <name>pkg:/[email protected],5.11-0.175.0.0.0.2.0</name> <name>pkg:/group/system/solaris-small-server</name> </software_data> </software> </ai_instance> </auto_install> root@ai-server:~# installadm create-manifest -n x86-fcs -d \ -f ./s11-fcs.small.local.xml root@ai-server:~# installadm list -m -n x86-fcs Manifest Status Criteria -------- ------ -------- S11 Small fcs local Default None orig_default Inactive None The major points in this new manifest are: Install "solaris-small-server" Install a few locales less than the default.  I'm not that fluid in French or Japanese... Use my own package service as publisher, running on IP address 192.168.2.12 Install the initial release of Solaris 11:  pkg:/[email protected],5.11-0.175.0.0.0.2.0 Using a similar approach, I'll create a default profile interactively and use it as a template for a few customized building blocks, each defining a part of the overall system configuration.  The modular approach makes it easy to configure numerous clients later on: root@ai-server:~# mkdir -p /export/install/configs/profiles root@ai-server:~# cd /export/install/configs/profiles root@ai-server:~# sysconfig create-profile -o default.xml root@ai-server:~# cp default.xml general.xml; cp default.xml mars.xml root@ai-server:~# cp default.xml user.xml root@ai-server:~# vi general.xml mars.xml user.xml root@ai-server:~# more general.xml mars.xml user.xml :::::::::::::: general.xml :::::::::::::: <!DOCTYPE service_bundle SYSTEM "/usr/share/lib/xml/dtd/service_bundle.dtd.1"> <service_bundle type="profile" name="sysconfig"> <service version="1" type="service" name="system/timezone"> <instance enabled="true" name="default"> <property_group type="application" name="timezone"> <propval type="astring" name="localtime" value="Europe/Berlin"/> </property_group> </instance> </service> <service version="1" type="service" name="system/environment"> <instance enabled="true" name="init"> <property_group type="application" name="environment"> <propval type="astring" name="LANG" value="C"/> </property_group> </instance> </service> <service version="1" type="service" name="system/keymap"> <instance enabled="true" name="default"> <property_group type="system" name="keymap"> <propval type="astring" name="layout" value="US-English"/> </property_group> </instance> </service> <service version="1" type="service" name="system/console-login"> <instance enabled="true" name="default"> <property_group type="application" name="ttymon"> <propval type="astring" name="terminal_type" value="vt100"/> </property_group> </instance> </service> <service version="1" type="service" name="network/physical"> <instance enabled="true" name="default"> <property_group type="application" name="netcfg"> <propval type="astring" name="active_ncp" value="DefaultFixed"/> </property_group> </instance> </service> <service version="1" type="service" name="system/name-service/switch"> <property_group type="application" name="config"> <propval type="astring" name="default" value="files"/> <propval type="astring" name="host" value="files dns"/> <propval type="astring" name="printer" value="user files"/> </property_group> <instance enabled="true" name="default"/> </service> <service version="1" type="service" name="system/name-service/cache"> <instance enabled="true" name="default"/> </service> <service version="1" type="service" name="network/dns/client"> <property_group type="application" name="config"> <property type="net_address" name="nameserver"> <net_address_list> <value_node value="192.168.2.1"/> </net_address_list> </property> </property_group> <instance enabled="true" name="default"/> </service> </service_bundle> :::::::::::::: mars.xml :::::::::::::: <!DOCTYPE service_bundle SYSTEM "/usr/share/lib/xml/dtd/service_bundle.dtd.1"> <service_bundle type="profile" name="sysconfig"> <service version="1" type="service" name="network/install"> <instance enabled="true" name="default"> <property_group type="application" name="install_ipv4_interface"> <propval type="astring" name="address_type" value="static"/> <propval type="net_address_v4" name="static_address" value="192.168.2.100/24"/> <propval type="astring" name="name" value="net0/v4"/> <propval type="net_address_v4" name="default_route" value="192.168.2.1"/> </property_group> <property_group type="application" name="install_ipv6_interface"> <propval type="astring" name="stateful" value="yes"/> <propval type="astring" name="stateless" value="yes"/> <propval type="astring" name="address_type" value="addrconf"/> <propval type="astring" name="name" value="net0/v6"/> </property_group> </instance> </service> <service version="1" type="service" name="system/identity"> <instance enabled="true" name="node"> <property_group type="application" name="config"> <propval type="astring" name="nodename" value="mars"/> </property_group> </instance> </service> </service_bundle> :::::::::::::: user.xml :::::::::::::: <!DOCTYPE service_bundle SYSTEM "/usr/share/lib/xml/dtd/service_bundle.dtd.1"> <service_bundle type="profile" name="sysconfig"> <service version="1" type="service" name="system/config-user"> <instance enabled="true" name="default"> <property_group type="application" name="root_account"> <propval type="astring" name="login" value="root"/> <propval type="astring" name="password" value="noIWillNotTellYouMyPasswordNotEvenEncrypted"/> <propval type="astring" name="type" value="role"/> </property_group> <property_group type="application" name="user_account"> <propval type="astring" name="login" value="stefan"/> <propval type="astring" name="password" value="noIWillNotTellYouMyPasswordNotEvenEncrypted"/> <propval type="astring" name="type" value="normal"/> <propval type="astring" name="description" value="Stefan Hinker"/> <propval type="count" name="uid" value="12345"/> <propval type="count" name="gid" value="10"/> <propval type="astring" name="shell" value="/usr/bin/bash"/> <propval type="astring" name="roles" value="root"/> <propval type="astring" name="profiles" value="System Administrator"/> <propval type="astring" name="sudoers" value="ALL=(ALL) ALL"/> </property_group> </instance> </service> </service_bundle> root@ai-server:~# installadm create-profile -n x86-fcs -f general.xml root@ai-server:~# installadm create-profile -n x86-fcs -f user.xml root@ai-server:~# installadm create-profile -n x86-fcs -f mars.xml \ -c ipv4=192.168.2.100 root@ai-server:~# installadm list -p Service Name Profile ------------ ------- x86-fcs general.xml mars.xml user.xml root@ai-server:~# installadm list -n x86-fcs -p Profile Criteria ------- -------- general.xml None mars.xml ipv4 = 192.168.2.100 user.xml None Here's the idea behind these files: "general.xml" contains settings valid for all my clients.  Stuff like DNS servers, for example, which in my case will always be the same. "user.xml" only contains user definitions.  That is, a root password and a primary user.Both of these profiles will be valid for all clients (for now). "mars.xml" defines network settings for an individual client.  This profile is associated with an IP-Address.  For this to work, I'll have to tweak the DHCP-settings in the next step: root@ai-server:~# installadm create-client -e 08:00:27:AA:3D:B1 -n x86-fcs root@ai-server:~# vi /etc/inet/dhcpd4.conf root@ai-server:~# tail -5 /etc/inet/dhcpd4.conf host 080027AA3DB1 { hardware ethernet 08:00:27:AA:3D:B1; fixed-address 192.168.2.100; filename "01080027AA3DB1"; } This completes the client preparations.  I manually added the IP-Address for mars to /etc/inet/dhcpd4.conf.  This is needed for the "mars.xml" profile.  Disabling arbitrary DHCP-replies will shut up this DHCP server, making my life in a shared environment a lot more peaceful ;-)Now, I of course want this installation to be completely hands-off.  For this to work, I'll need to modify the grub boot menu for this client slightly.  You can find it in /etc/netboot.  "installadm create-client" will create a new boot menu for every client, identified by the client's MAC address.  The template for this can be found in a subdirectory with the name of the install service, /etc/netboot/x86-fcs in our case.  If you don't want to change this manually for every client, modify that template to your liking instead. root@ai-server:~# cd /etc/netboot root@ai-server:~# cp menu.lst.01080027AA3DB1 menu.lst.01080027AA3DB1.org root@ai-server:~# vi menu.lst.01080027AA3DB1 root@ai-server:~# diff menu.lst.01080027AA3DB1 menu.lst.01080027AA3DB1.org 1,2c1,2 < default=1 < timeout=10 --- > default=0 > timeout=30 root@ai-server:~# more menu.lst.01080027AA3DB1 default=1 timeout=10 min_mem64=0 title Oracle Solaris 11 11/11 Text Installer and command line kernel$ /x86-fcs/platform/i86pc/kernel/$ISADIR/unix -B install_media=htt p://$serverIP:5555//export/install/fcs,install_service=x86-fcs,install_svc_addre ss=$serverIP:5555 module$ /x86-fcs/platform/i86pc/$ISADIR/boot_archive title Oracle Solaris 11 11/11 Automated Install kernel$ /x86-fcs/platform/i86pc/kernel/$ISADIR/unix -B install=true,inst all_media=http://$serverIP:5555//export/install/fcs,install_service=x86-fcs,inst all_svc_address=$serverIP:5555,livemode=text module$ /x86-fcs/platform/i86pc/$ISADIR/boot_archive Now just boot the client off the network using PXE-boot.  For my demo purposes, that's a client from VirtualBox, of course.  That's all there's to it.  And despite the fact that this blog entry is a little longer - that wasn't that hard now, was it?

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• Reading data from an Entity Framework data model through a WCF Data Service

  - by nikolaosk

  This is going to be the fourth post of a series of posts regarding ASP.Net and the Entity Framework and how we can use Entity Framework to access our datastore. You can find the first one here , the second one here and the third one here . I have a post regarding ASP.Net and EntityDataSource. You can read it here .I have 3 more posts on Profiling Entity Framework applications. You can have a look at them here , here and here . Microsoft with .Net 3.0 Framework, introduced WCF. WCF is Microsoft's...(read more)

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• The Interaction between Three-Tier Client/Server Model and Three-Tier Application Architecture Model

  The three-tier client/server model is a network architectural approach currently used in modern networking. This approach divides a network in to three distinct components. Three-Tier Client/Server Model Components Client Component Server Component Database Component The Client Component of the network typically represents any device on the network. A basic example of this would be computer or another network/web enabled devices that are connected to a network. Network clients request resources on the network, and are usually equipped with a user interface for the presentation of the data returned from the Server Component. This process is done through the use of various software clients, and example of this can be seen through the use of a web browser client. The web browser request information from the Server Component located on the network and then renders the results for the user to process. The Server Components of the network return data based on specific client request back to the requesting client.  Server Components also inherit the attributes of a Client Component in that they are a device on the network and that they can also request information from other Server Components. However what differentiates a Client Component from a Server Component is that a Server Component response to requests from devices on the network. An example of a Server Component can be seen in a web server. A web server listens for new requests and then interprets the request, processes the web pages, and then returns the processed data back to the web browser client so that it may render the data for the user to interpret. The Database Component of the network returns unprocessed data from databases or other resources. This component also inherits attributes from the Server Component in that it is a device on a network, it can request information from other server components and database components, and it also listens for new requests so that it can return data when needed. The three-tier client/server model is very similar to the three-tier application architecture model, and in fact the layers can be mapped to one another. Three-Tier Application Architecture Model Presentation Layer/Logic Business Layer/Logic Data Layer/Logic The Presentation Layer including its underlying logic is very similar to the Client Component of the three-tiered model. The Presentation Layer focuses on interpreting the data returned by the Business Layer as well as presents the data back to the user.  Both the Presentation Layer and the Client Component focus primarily on the user and their experience. This allows for segments of the Business Layer to be distributable and interchangeable because the Presentation Layer is not directly integrated in with Business Layer. The Presentation Layer does not care where the data comes from as long as it is in the proper format. This allows for the Presentation Layer and Business Layer to be stored on one or more different servers so that it can provide a higher availability to clients requesting data. A good example of this is a web site that uses load balancing. When a web site decides to take on the task of load balancing they must obtain a network device that sits in front of a one or machines in order to distribute the request across multiple servers. When a user comes in through the load balanced device they are redirected to a specific server based on a few factors. Common Load Balancing Factors Current Server Availability Current Server Response Time Current Server Priority The Business Layer and corresponding logic are business rules applied to data prior to it being sent to the Presentation Layer. These rules are used to manipulate the data coming from the Data Access Layer, in addition to validating any data prior to being stored in the Data Access Layer. A good example of this would be when a user is trying to create multiple accounts under one email address. The Business Layer logic can prevent duplicate accounts by enforcing a unique email for every new account before the data is even stored in the Data Access Layer. The Server Component can be directly tied to this layer in that the server typically stores and process the Business Layer before it is returned to the end-user via the Presentation Layer. In addition the Server Component can also run automated process through the Business Layer on the data in the Data Access Layer so that additional business analysis can be derived from the data that has been already collected. The Data Layer and its logic are responsible for storing information so that it can be easily retrieved. Typical in most modern applications data is stored in a database management system however data can also be in the form of files stored on a file server. In addition a database can take on one of several forms. Common Database Formats XML File Pipe Delimited File Tab Delimited File Comma Delimited File (CSV) Plain Text File Microsoft Access Microsoft SQL Server MySql Oracle Sybase The Database component of the Networking model can be directly tied to the Data Layer because this is where the Data Layer obtains the data to return back the Business Layer. The Database Component basically allows for a place on the network to store data for future use. This enables applications to save data when they can and then quickly recall the saved data as needed so that the application does not have to worry about storing the data in memory. This prevents overhead that could be created when an application must retain all data in memory. As you can see the Three-Tier Client/Server Networking Model and the Three-Tiered Application Architecture Model rely very heavily on one another to function especially if different aspects of an application are distributed across an entire network. The use of various servers and database servers are wonderful when an application has a need to distribute work across the network. Network Components and Application Layers Interaction Database components will store all data needed for the Data Access Layer to manipulate and return to the Business Layer Server Component executes the Business Layer that manipulates data so that it can be returned to the Presentation Layer Client Component hosts the Presentation Layer that  interprets the data and present it to the user

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• C# coding standards” Use the const directive only on natural constants

  - by Nathan Wilfert

  I've seen these 2 guidelines in coding c# standard and I’m not sure the what the 2nd one means. With the exception of zero and one, never hard-code a numeric value; always declare a constant instead. Use the const directive only on natural constants such as the number of days of the week. 1st what is the definition of a natural constants and if the number is not a natural constants given the 1st rule how does one declare a constant in c# without the const directive? See http://www.scribd.com/doc/10731655/IDesign-C-Coding-Standard-232 for reference.

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• .NET Framework 4.0 mysteriously loses track of System.EnterpriseServices

  - by Lorin Thwaits

  The GAC in .NET 4.0 is cut into two parts now -- one half for .NET Framework 2.0 stuff, and the other for v4.0 stuff. When compiling any project, targeting .NET 2.0, 3.5, or what have you, this annoying error may pop up: Could not load file or assembly 'System.EnterpriseServices, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified. In that case, open a run box and perform this copy command: xcopy %ProgramFiles%\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0\System.EnterpriseServices.dll %windir%\Microsoft.NET\assembly\GAC_32\System.EnterpriseServices\v4.0_4.0.0.0__b03f5f7f11d50a3a /e This reconstructs the proper portion of the GAC for that one missing file.

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• Nerdstock 2012: A photo review of Microsoft TechEd North America 2012

  - by The Un-T Guy

  Not only could I not fathom that I would ever be attending a tech event of the magnitude of TechEd, neither could any of my co-workers.  As the least technical person in the history of Information Technology ever, I felt as though I were walking into the belly of the beast, fearing I’d not be allowed out until I could write SSIS packages, program in Visual Basic, or at least arm wrestle a DBA.  Most of my fears were unrealized.   But I made it.  I was here.  I even got to wear the Mark of the Geek neck package with schedule, eyeglass cleaners, name badge (company name obfuscated so they don’t fire me), and a pen.  The name  badge was seemingly the key element, as every vendor in the place wanted to scan it to capture name, email address, and numbers to show their bosses back home.  It also let me eat the food and drink the coffee so that’s a fair trade.   A recurring theme throughout the presentations and vendor demos was “the Cloud” and BYOD (bring your own device).  The below was a common site throughout the week, as attendees from all over the world brought their own devices and were able to (seemingly) seamlessly connect to the Worldwide Innerwebs.  Apparently proof that Microsoft and the event organizers were practicing what they were preaching.   “Cavernous” is one way to describe the downstairs facility itself.  “Freaking cavernous” might be more accurate.  Work sessions were held in classrooms on the second and third floors but the real action was happening downstairs.  Microsoft bookstore, blogger hub (shoutout to Geekswithblogs.net), The Wall (sans Pink Floyd, sadly), couches, recharging stations…   …a game zone with pool and air hockey tables, pinball machines, foosball…   …vintage video games…           …and a even giant chess board.  Looked like this guy was opening with the Kaspersky parry.   The blend of technology and fantasy even went so far as to bring childhood favorites to life.  Assuming, of course, your childhood was pre-video games (like mine) and you were stuck with electric football and Rock ‘em Sock ‘em robots:   And, lest the “combatants” become unruly or – God forbid – afternoon snacks were late, Orange County’s finest was on the scene to keep the peace.  On a high-tech mode of transport, of course.   She wasn’t the only one to think this was a swell way to transition from one concourse to the next.  Given the level of support provided by the entire Orange County Convention Center staff, I knew they had to have some secret.   Here’s one entrance to the vendor zone/”Technical Learning Center.”  Couldn’t help but think of them as the remora attached to the Whale Shark that is Microsoft…   …or perhaps planets orbiting the sun. Microsoft is just that huge and it seemed like every vendor in the industry looks forward to partnering with the tech behemoth.   Aside from the free stuff from the vendors, probably the most popular place in the house was the dining area.  Amazing spreads every day, multiple times a day.  While no attendance numbers were available at press time, literally thousands of attendees were fed, and fed well, every day.  And lest you think my post from earlier in the week exaggerated about the backpacks…   …or that I’m exaggerating about the lunch crowds.  This represents only about between 25-30% of the lunch crowd – it was all my camera could capture at once.  No one went away hungry.   The only thing missing was a a vat of Red Bull but apparently organizers went old school, with probably 100 urns of the original energy drink – coffee – all around the venue.   Of course, following lunch and afternoon sessions, some preferred the even older school method of re-energizing.  There were rumors that Microsoft was serving graham crackers and milk in this area.  But they were only rumors.   Cannot overstate the wonderful service provided by the Orange County Convention Center staff.  Coffee, soft drinks, juice, and water were available always.  Buffet meals were delicious with a wide range of healthy options available, in addition to hundreds (at least) special meal requests supported every day.  Ever tried to keep up with an estimated 9,000 hungry and thirsty IT-ers?  These folks did.  Kudos to all of the staff and many thanks!   And while I occasionally poke fun at the Whale Shark, if nothing else this experience convinced me of one thing:  Microsoft knows how to put on a professional event.  Hundreds of informative, professionally delivered sessions, covering a wide range of topics set at varying levels of expertise (some that even I was able to follow), social activities, vendor partnerships…they brought everything you could ask for to inform, educate, and inspire an entire IT industry.   So as I depart the belly of the beast, I can both take pride in the fact that I survived the week and marvel at the brilliance surrounding me.  The IT industry – or at least the segment associated with Microsoft – is in good, professional hands.  And what won’t fit in their hands can be toted in the Microsoft provided backpacks.  Win-win.   Until New Orleans…

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• MAAS not working

  - by Zimika

  I'm trying a whole week to make MASS to work, but no results. This is the procedure: maas createsuperuser sudo apt-get install maas-dhcp maas-import-isos apt-get install maas-enlist tftpd-hpa maas-import-isos After this I start node machine with PXE as default first boot device, and select option maas-enlist. Sistem start to installing some things, and after that on MAAS WebUI stand 1 node. But when I click on Node button on WebUI or refresh page, it show 0 node. Command cobbler system list showing: root@maas-serv:~# cobbler system list default node-3ee116ea-a8b2-11e1-a735-50e549e38206 Also, sometime this procedure register one node, but when registering second one, same problem like I described up. root@maas-serv:/var/lib/tftpboot/pxelinux.cfg# is empty, only default is there. On command maas-import-isos there is a one warning. ftpboot/images/precise-x86_64-maas-ephemeral/initrd copying images generating GPXE/PXE configuration files generating PXE menu structure warning: kernel option length exceeds 255 warning: kernel option length exceeds 255 warning: kernel option length exceeds 255 warning: kernel option length exceeds 255 copying files for distro: precise-x86_64

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• Algorithmia Source Code released on CodePlex

  - by FransBouma

  Following the release of our BCL Extensions Library on CodePlex, we have now released the source-code of Algorithmia on CodePlex! Algorithmia is an algorithm and data-structures library for .NET 3.5 or higher and is one of the pillars LLBLGen Pro v3's designer is built on. The library contains many data-structures and algorithms, and the source-code is well documented and commented, often with links to official descriptions and papers of the algorithms and data-structures implemented. The source-code is shared using Mercurial on CodePlex and is licensed under the friendly BSD2 license. User documentation is not available at the moment but will be added soon. One of the main design goals of Algorithmia was to create a library which contains implementations of well-known algorithms which weren't already implemented in .NET itself. This way, more developers out there can enjoy the results of many years of what the field of Computer Science research has delivered. Some algorithms and datastructures are known in .NET but are re-implemented because the implementation in .NET isn't efficient for many situations or lacks features. An example is the linked list in .NET: it doesn't have an O(1) concat operation, as every node refers to the containing LinkedList object it's stored in. This is bad for algorithms which rely on O(1) concat operations, like the Fibonacci heap implementation in Algorithmia. Algorithmia therefore contains a linked list with an O(1) concat feature. The following functionality is available in Algorithmia: Command, Command management. This system is usable to build a fully undo/redo aware system by building your object graph using command-aware classes. The Command pattern is implemented using a system which allows transparent undo-redo and command grouping so you can use it to make a class undo/redo aware and set properties, use its contents without using commands at all. The Commands namespace is the namespace to start. Classes you'd want to look at are CommandifiedMember, CommandifiedList and KeyedCommandifiedList. See the CommandQueueTests in the test project for examples. Graphs, Graph algorithms. Algorithmia contains a sophisticated graph class hierarchy and algorithms implemented onto them: non-directed and directed graphs, as well as a subgraph view class, which can be used to create a view onto an existing graph class which can be self-maintaining. Algorithms include transitive closure, topological sorting and others. A feature rich depth-first search (DFS) crawler is available so DFS based algorithms can be implemented quickly. All graph classes are undo/redo aware, as they can be set to be 'commandified'. When a graph is 'commandified' it will do its housekeeping through commands, which makes it fully undo-redo aware, so you can remove, add and manipulate the graph and undo/redo the activity automatically without any extra code. If you define the properties of the class you set as the vertex type using CommandifiedMember, you can manipulate the properties of vertices and the graph contents with full undo/redo functionality without any extra code. Heaps. Heaps are data-structures which have the largest or smallest item stored in them always as the 'root'. Extracting the root from the heap makes the heap determine the next in line to be the 'maximum' or 'minimum' (max-heap vs. min-heap, all heaps in Algorithmia can do both). Algorithmia contains various heaps, among them an implementation of the Fibonacci heap, one of the most efficient heap datastructures known today, especially when you want to merge different instances into one. Priority queues. Priority queues are specializations of heaps. Algorithmia contains a couple of them. Sorting. What's an algorithm library without sort algorithms? Algorithmia implements a couple of sort algorithms which sort the data in-place. This aspect is important in situations where you want to sort the elements in a buffer/list/ICollection in-place, so all data stays in the data-structure it already is stored in. PropertyBag. It re-implements Tony Allowatt's original idea in .NET 3.5 specific syntax, which is to have a generic property bag and to be able to build an object in code at runtime which can be bound to a property grid for editing. This is handy for when you have data / settings stored in XML or other format, and want to create an editable form of it without creating many editors. IEditableObject/IDataErrorInfo implementations. It contains default implementations for IEditableObject and IDataErrorInfo (EditableObjectDataContainer for IEditableObject and ErrorContainer for IDataErrorInfo), which make it very easy to implement these interfaces (just a few lines of code) without having to worry about bookkeeping during databinding. They work seamlessly with CommandifiedMember as well, so your undo/redo aware code can use them out of the box. EventThrottler. It contains an event throttler, which can be used to filter out duplicate events in an event stream coming into an observer from an event. This can greatly enhance performance in your UI without needing to do anything other than hooking it up so it's placed between the event source and your real handler. If your UI is flooded with events from data-structures observed by your UI or a middle tier, you can use this class to filter out duplicates to avoid redundant updates to UI elements or to avoid having observers choke on many redundant events. Small, handy stuff. A MultiValueDictionary, which can store multiple unique values per key, instead of one with the default Dictionary, and is also merge-aware so you can merge two into one. A Pair class, to quickly group two elements together. Multiple interfaces for helping with building a de-coupled, observer based system, and some utility extension methods for the defined data-structures. We regularly update the library with new code. If you have ideas for new algorithms or want to share your contribution, feel free to discuss it on the project's Discussions page or send us a pull request. Enjoy!

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• Browsing Your ADF Application Module Pooling Params with WLST

  - by Duncan Mills

  In ADF 11g you can of course use Enterprise Manager (EM) to browse and configure the settings used by ADF Business Components  Application Modules, as shown here for one of my sample deployed applications. This screen you can access from the EM homepage by pulling down the Application Deployment menu, and then ADF > Configure ADF Business Components. Then select the profile that you are actually using (Hint: look in the DataBindings.cpx file to work this out - probably the "Local" version unless you've explicitly changed it. )So, from this screen you can change the pooling parameters and the world is good. But what if you don't have EM installed? In that case you can use the WebLogic scripting capabilities to view (and Update) the MBean Properties. Explanation The pooling parameters and many others are handled through Message Driven Beans that are created for the deployed application in the server. In the case of the ADF BC pooling parameters, this MBean will combine the configuration deployed as part of the application, along with any overrides defined as -D environement commands on the JVM startup for the application server instance. Using WLST to Browse the Bean ValuesFor our purposes here I'm doing this interactively, although you can also write a script or write Java to achieve the same thing.Step 0: Before You Start You will need the followingAccess to the console on the machine that is running the serverThe WebLogic Admin username and password (I'll use weblogic/password as my example here - yours will be different)The name of the deployed application (in this example FMWdh_application1)The package path to the bc4j.xcfg file (in this example oracle.demo.fmwdh.model.service.common.bc4j.xcfg) This is based on the default path for your model project so it shoudl be fairly easy to work out.The BC configuration your AM is actually running with (look in the DataBindings.cpx for that. In this example DealHelpServiceDeployed is the profile being used..)Step 1: Start the WLST consoleTo start at the beginning, you need to run the WLST command but that needs a little setup:Change to the wlserver_10.3/server/bin directory e.g. under your Fusion Middleware Home[oracle@mymachine] cd /home/oracle/FMW_R1/wlserver_10.3/server/binSet your environment using the setWLSEnv script. e.g. on Oracle Enterprise Linux:[oracle@mymachine bin] source setWLSEnv.shStart the WLST interactive console[oracle@mymachine bin] java weblogic.WLSTInitializing WebLogic Scripting Tool (WLST) ...Welcome to WebLogic Server Administration Scripting ShellType help() for help on available commandswls:/offline> Step 2:Enter the WLST commandsConnect to the server wls:> connect('weblogic','password')Change to the Custom root, this is where the AMPooling MBeans are registered wls:> custom()Change to the b4j MBean directorywls:> cd ('oracle.bc4j.mbean.config')Work out the correct directory for the AM configuration you need. This is the difficult bit, not because it's hard to do, but because the names are long. The structure here is such that every child MBean is displayed at the same level as the parent, so for each deployed application there will be many directories shown. In fact, do an ls() command here and you'll see what I mean. Each application will have one MBean for the app as a whole, and then for each deployed configuration in the .xcfg file you'll see: One for the config entry itself, and then one each for Security, DB Connection and AM Pooling. So if you deploy an app with just one configuration you'll see 5 directories, if it has two configurations in the .xcfg you'll see 9 and so on.The directory you are looking for will contain those bits of information you gathered in Step 0, specifically the Application Name, the configuration you are using and the xcfg name: First of all narrow your list to just those directories returned from the ls() command that begin oracle.bc4j.mbean.config:name=AMPool. These identify the AM pooling MBeans for all the deployed applications. Now look for the correct application name e.g. Application=FMWdh_application1The config setting in that sub-list should already be correct and match what you expect e.g. oracle.bc4j.mbean.config=oracle.demo.fmwdh.model.service.common.bc4j.xcfgFinally look for the correct value for the AppModuleConfigType e.g. oracle.bc4j.mbean.config.AppModuleConfigType=DealHelpServiceDeployedNow you have identified the correct directory name, change to that (keep the name on one line of course - I've had to split it across lines here for clarity:wls:> cd ('oracle.bc4j.mbean.config:name=AMPool,     type=oracle.bc4j.mbean.config.AppModuleConfigType.AMPoolType,    oracle.bc4j.mbean.config=oracle.demo.fmwdh.model.service.common.bc4j.xcfg,    Application=FMWdh_application1,    oracle.bc4j.mbean.config.AppModuleConfigType=DealHelpServiceDeployed') Now you can actually view the parameter values with a simple ls() commandwls:> ls()And here's the output in which you can view the realtime values of the various pool settings: -rw- AmpoolConnectionstrategyclass oracle.jbo.common.ampool.DefaultConnectionStrategy -rw- AmpoolDoampooling true -rw- AmpoolDynamicjdbccredentials false -rw- AmpoolInitpoolsize 2 -rw- AmpoolIsuseexclusive true -rw- AmpoolMaxavailablesize 40 -rw- AmpoolMaxinactiveage 600000 -rw- AmpoolMaxpoolsize 4096 -rw- AmpoolMinavailablesize 2 -rw- AmpoolMonitorsleepinterval 600000 -rw- AmpoolResetnontransactionalstate true -rw- AmpoolSessioncookiefactoryclass oracle.jbo.common.ampool.DefaultSessionCookieFactory -rw- AmpoolTimetolive 3600000 -rw- AmpoolWritecookietoclient false -r-- ConfigMBean true -rw- ConnectionPoolManager oracle.jbo.server.ConnectionPoolManagerImpl -rw- Doconnectionpooling false -rw- Dofailover false -rw- Initpoolsize 0 -rw- Maxpoolcookieage -1 -rw- Maxpoolsize 4096 -rw- Poolmaxavailablesize 25 -rw- Poolmaxinactiveage 600000 -rw- Poolminavailablesize 5 -rw- Poolmonitorsleepinterval 600000 -rw- Poolrequesttimeout 30000 -rw- Pooltimetolive -1 -r-- ReadOnly false -rw- Recyclethreshold 10 -r-- RestartNeeded false -r-- SystemMBean false -r-- eventProvider true -r-- eventTypes java.lang.String[jmx.attribute.change] -r-- objectName oracle.bc4j.mbean.config:name=AMPool,type=oracle.bc4j.mbean.config.AppModuleConfigType.AMPoolType,oracle.bc4j.mbean.config=oracle.demo.fmwdh.model.service.common.bc4j.xcfg,Application=FMWdh_application1,oracle.bc4j.mbean.config.AppModuleConfigType=DealHelpServiceDeployed -rw- poolClassName oracle.jbo.common.ampool.ApplicationPoolImpl Thanks to Brian Fry on the JDeveloper PM Team who did most of the work to put this sequence of steps together with me badgering him over his shoulder.

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• Agile Testing Days 2012 – Day 1 – The birth of the #unicorn…

  - by Chris George

  Still riding the high from the tutorial day, I arrived at the conference venue eager to get cracking with the days talks. The opening Keynote was “Disciplined Agile Delivery: The Foundation for Scaling Agile” presented by Scott Ambler. The general ideas behind the methodology such as not re-inventing the wheel, and being goal driven, not prescriptive in how you work certainly struck chords with how we are trying to work in my team. Scott made some interesting observations about how scrum is quite prescriptive and is this really agile? I agreed with quite a few of his points on how what works for one team may not work for another. How a team works should be driven by context and reflection, not process and prescription. However was somewhat dubious about some of the statistics he rolled out towards the end. However, out of this keynote was born something that was to transcend this one presentation. During the talk, Scott mentioned on more than one occasion “In the real world”, and at one point made reference to people living in the land of unicorns and rainbows. The challenge was then laid down on twitter for all speakers to include a unicorn in their presentations… and for the most part this happened! It became an identity for this years conference, and I’m sure something that any attendee will always associate with Agile Testing Days 2012! Following this keynote, I attended “Going agile with Automated GUI Testing – Some personal insights” by Jan Zdunek from codecentric on the vendor track. My speciality is test automation, and in particular GUI testing, so this drew me to this talk more than the others. Thankfully, it was made clear from the very start that this was not peddling any particular product (even though it was on the vendor track), and Jan faithfully stuck to that. Most of the content was not new to me, but it was really comforting to hear someone else with very similar experiences to my own. In particular, things like how GUI testing is hard and is not a silver bullet; how record & replay is NOT a good thing to do (which drew a somewhat inflammatory tweet from an automation company when I tweeted that!). Something that I have started hearing around the place, and has certainly been murmuring at work is to push more of the automation coding onto the developers. After all they are the coding experts. I agree with this to a degree, but I personally enjoy coding and find it very rewarding doing so, therefore I’d be reluctant to give it up. I think there are some better alternatives such as pairing with a developer. Lastly, Jan mentioned, almost in passing, that we should consider virtualisation for gui testing for covering configuration combinations. On my project we’ve been running our win32/.NET GUI tests in cloud virtualisation for a couple of years now… I really should write about that! After lunch the second keynote of the day was by Lisa Crispin and Janet Gregory,”Myths about Agile Testing, De-Bunked”. It started off well… with the two ladies donning Medusa style head bands whilst they disbanding several myths about agile testing! I got the impression that it was perhaps not as slick as they would have liked, but then Janet was suffering with a very sore throat so kept losing her voice. Nevertheless, the presentation was captivating, and they debunked several myths such as : “Testing is dead”, “Testers must write code”, “Agile teams always deliver faster”. I didn’t take many notes for this because it was being recorded, but unfortunately the recordings have not been posted yet so I’ll write more about this when they are. The TestLab was held during a somewhat free for all time during most of the afternoon. It looked intriguing and proved to be one of the surprising experiences of the conference for me. Run by James Lyndsay and Bart Knaack, it consisted of a number of ‘stations’ that offered different testing problems. I opted for testing a mathematical drawing app call Geogebra, the task being to pair up and exploratory test it. After an allotted time, we discussed issues we’d found and decided if we wanted to continue ‘playing’ to which we all agreed! It was fun! The last track talk of the day was “Developers Exploratory Testing – Raising the bar” by Sigge Birgisson. One of the teams at Red Gate have tried Dev or Team exploratory testing a couple of times, and I was really interested to go to the presentation that prompted that. I was not disappointed! Sigge gave a first class presentation, and not only explained what DET was all about, but also how to go about implementing it. Little tips like calling it a ‘workshop’ rather than ‘testing’ I can really see working! Monday evening saw the presentation of the award for the Most Influential Agile Testing Professional Person go to a much deserved Lisa Crispin. The evening was great, with acrobatics, magic and music. My Takeaway Triple from Day 1:  Some of the cool stuff that was suggested in the GUI Testing talk, we are already doing. I should write about that! Testing is not dead! Perhaps testing will become more of a skill than a specific role, but it is certainly not dead. Team/Developer exploratory testing… seems like a no-brainer assuming you have a team who is willing.  Day 2 – Coming soon…

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• OpenGL ES 2.0: Using VBOs?

  - by Bunkai.Satori

  OpenGL VBOs (vertex buffer objects) have been developed to improve performance of OpenGL (OpenGL ES 2.0 in my case). The logic is that with the help of VBOs, the data does not need to be copied from client memory to graphics card on per frame basis. However, as I see it, the game scene changes continuously: position of objects change, their scaling and rotating change, they get animated, they explode, they get spawn or disappear. In such highly dynamic environment, such as computer game scene is, what is the point of using VBOs, if the VBOs would need to be constructed on per-frame basis anyway? Can you please help me to understand how to practically take beneif of VBOs in computer games? Can there be more vertex based VBOs (say one per one object) or there must be always exactly only one VBO present for each draw cycle?

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• Initial Review - Mastering Unreal Technology I: Introduction to Level Design with Unreal Engine 3

  - by Matt Christian

  Recently I purchased 3 large volumes on using the Unreal 3 Engine to create levels and custom games.  This past weekend I cracked the spine of the first and started reading.  Here are my early impressions (I'm ~250 pages into it, with appendices it's about 900). Pros Interestingly, the book starts with an overview of the Unreal engines leading up to Unreal 3 (including Gears of War) and follows with some discussion on planning a mod and what goes into the game development process.  This is nice for an intro to the book and is much preferred rather than a simple chapter detailing what is on the included CD, how to install and setup UnrealEd, etc...  While the chapter on Unreal history and planning can be considered 'fluff', it's much less 'fluffy' than most books provide. I need to mention one thing here that is pretty crucial in the way I'm going to continue reviewing this book.  Most technical books like this are used as a shelf reference; as a thick volume you use for looking up techniques every now and again.  Even so, I prefer reading from cover to cover, including chapters I may already be knowledgable on (I'm sure this is typical for most people).  If there was a chapter on installing UnrealEd (the previously mentioned 'fluff'), I would probably force myself to read it, even though I've installed the game and engine multiple times on different systems. Chapter 3 is where we really get to the introduction piece of UnrealEd, creating your first basic level.  This large chapter details creating two small rooms, adding static meshes, adding lighting, creating and adding particle emitters, creating a door that animates with Unreal Matinee and Kismet, static meshes with physics, and other little additions to make your level look less beginner.  This really is a chapter that overviews the entire rest of the book, as each chapter following details the creation and intermediate usages of Static Meshes, Materials, Lighting, etc... One other very nice part to this book is the way the tutorials are setup.  Each tutorial builds off the previous and all are step-by-step.  If you haven't completed one yet, you can find all the starting files on the CD that comes with the book. Cons While the description of the overview chapter (Chapter 3) is fresh in your mind, let me start the cons by saying this chapter is setup extremely confusing for the noob.  At one point, you end up creating a door mesh and setting it up as a InteropMesh so that it is ready to be animated, only to switch to particles and spend a good portion of time working on a different piece of the level.  Yes, this is actually how I develop my levels (jumping back and forth), though it's very odd for a book to jump out of sequence. The next item might be a positive or a negative depending on your skill level with UnrealEd.  Most of the introduction to the editor layout is found in one of the Appendices instead of before Chapter 3.  For new readers, this might lead to confusion as Appendix A would typically be read between Chapter 2 and 3.  However, this is a positive for those with some experience in UnrealEd as they don't have to force themselves through a 'learn every editor button' chapter.  I'm listing this in the Cons section as the book is 'Introduction to...' and is probably going to be directed toward a lot of very beginner developers. Finally, there's a lack of general description to a lot of the underlying engine and what each piece in UnrealEd is or does.  Sometimes you'll be performing Tutorial after Tutorial with barely a paragraph in between describing ANY of what you've just done.  Tutorial 1.1 Step 6 says to press Button X, so you do.  But why?  This is in part a problem with the structure of the tutorials rather than the content of the book.  Since the tutorials are so focused on a step-by-step (or procedural) description of a process, you learn the process and not why you're doing that.  For example, you might learn how to size a material to a surface, but will only learn what buttons to press and not what each one does. This becomes extremely apparent in the chapter on Static Meshes as most of the chapter is spent in 3D Studio Max.  Since there are books on 3DSM and modelling, the book really only tells you the steps and says to go grab a book on modelling if you're really interested in 3DSM.  Again, I've learned the process to develop my own meshes in 3DSM, but I don't know the why behind the steps. Conclusion So far the book is very good though I would have a hard time recommending it to a complete beginner.  I would suggest anyone looking at this book (obviously including the other 2, more advanced volumes) to pick up a copy of UDK or Unreal 3 (available online or via download services such as Steam) and watch some online tutorials and play with it first.  You'll find plenty of online videos available that were created by the authors and may suit as a better introduction to the editor.

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• NET Math Libraries

  - by JoshReuben

  NET Mathematical Libraries   .NET Builder for Matlab The MathWorks Inc. - http://www.mathworks.com/products/netbuilder/ MATLAB Builder NE generates MATLAB based .NET and COM components royalty-free deployment creates the components by encrypting MATLAB functions and generating either a .NET or COM wrapper around them. .NET/Link for Mathematica www.wolfram.com a product that 2-way integrates Mathematica and Microsoft's .NET platform call .NET from Mathematica - use arbitrary .NET types directly from the Mathematica language. use and control the Mathematica kernel from a .NET program. turns Mathematica into a scripting shell to leverage the computational services of Mathematica. write custom front ends for Mathematica or use Mathematica as a computational engine for another program comes with full source code. Leverages MathLink - a Wolfram Research's protocol for sending data and commands back and forth between Mathematica and other programs. .NET/Link abstracts the low-level details of the MathLink C API. Extreme Optimization http://www.extremeoptimization.com/ a collection of general-purpose mathematical and statistical classes built for the.NET framework. It combines a math library, a vector and matrix library, and a statistics library in one package. download the trial of version 4.0 to try it out. Multi-core ready - Full support for Task Parallel Library features including cancellation. Broad base of algorithms covering a wide range of numerical techniques, including: linear algebra (BLAS and LAPACK routines), numerical analysis (integration and differentiation), equation solvers. Mathematics leverages parallelism using .NET 4.0's Task Parallel Library. Basic math: Complex numbers, 'special functions' like Gamma and Bessel functions, numerical differentiation. Solving equations: Solve equations in one variable, or solve systems of linear or nonlinear equations. Curve fitting: Linear and nonlinear curve fitting, cubic splines, polynomials, orthogonal polynomials. Optimization: find the minimum or maximum of a function in one or more variables, linear programming and mixed integer programming. Numerical integration: Compute integrals over finite or infinite intervals, over 2D and higher dimensional regions. Integrate systems of ordinary differential equations (ODE's). Fast Fourier Transforms: 1D and 2D FFT's using managed or fast native code (32 and 64 bit) BigInteger, BigRational, and BigFloat: Perform operations with arbitrary precision. Vector and Matrix Library Real and complex vectors and matrices. Single and double precision for elements. Structured matrix types: including triangular, symmetrical and band matrices. Sparse matrices. Matrix factorizations: LU decomposition, QR decomposition, singular value decomposition, Cholesky decomposition, eigenvalue decomposition. Portability and performance: Calculations can be done in 100% managed code, or in hand-optimized processor-specific native code (32 and 64 bit). Statistics Data manipulation: Sort and filter data, process missing values, remove outliers, etc. Supports .NET data binding. Statistical Models: Simple, multiple, nonlinear, logistic, Poisson regression. Generalized Linear Models. One and two-way ANOVA. Hypothesis Tests: 12 14 hypothesis tests, including the z-test, t-test, F-test, runs test, and more advanced tests, such as the Anderson-Darling test for normality, one and two-sample Kolmogorov-Smirnov test, and Levene's test for homogeneity of variances. Multivariate Statistics: K-means cluster analysis, hierarchical cluster analysis, principal component analysis (PCA), multivariate probability distributions. Statistical Distributions: 25 29 continuous and discrete statistical distributions, including uniform, Poisson, normal, lognormal, Weibull and Gumbel (extreme value) distributions. Random numbers: Random variates from any distribution, 4 high-quality random number generators, low discrepancy sequences, shufflers. New in version 4.0 (November, 2010) Support for .NET Framework Version 4.0 and Visual Studio 2010 TPL Parallellized – multicore ready sparse linear program solver - can solve problems with more than 1 million variables. Mixed integer linear programming using a branch and bound algorithm. special functions: hypergeometric, Riemann zeta, elliptic integrals, Frensel functions, Dawson's integral. Full set of window functions for FFT's. Product  Price Update subscription Single Developer License $999  $399  Team License (3 developers) $1999  $799  Department License (8 developers) $3999  $1599  Site License (Unlimited developers in one physical location) $7999  $3199    NMath http://www.centerspace.net .NET math and statistics libraries matrix and vector classes random number generators Fast Fourier Transforms (FFTs) numerical integration linear programming linear regression curve and surface fitting optimization hypothesis tests analysis of variance (ANOVA) probability distributions principal component analysis cluster analysis built on the Intel Math Kernel Library (MKL), which contains highly-optimized, extensively-threaded versions of BLAS (Basic Linear Algebra Subroutines) and LAPACK (Linear Algebra PACKage). Product  Price Update subscription Single Developer License $1295 $388 Team License (5 developers) $5180 $1554   DotNumerics http://www.dotnumerics.com/NumericalLibraries/Default.aspx free DotNumerics is a website dedicated to numerical computing for .NET that includes a C# Numerical Library for .NET containing algorithms for Linear Algebra, Differential Equations and Optimization problems. The Linear Algebra library includes CSLapack, CSBlas and CSEispack, ports from Fortran to C# of LAPACK, BLAS and EISPACK, respectively. Linear Algebra (CSLapack, CSBlas and CSEispack). Systems of linear equations, eigenvalue problems, least-squares solutions of linear systems and singular value problems. Differential Equations. Initial-value problem for nonstiff and stiff ordinary differential equations ODEs (explicit Runge-Kutta, implicit Runge-Kutta, Gear's BDF and Adams-Moulton). Optimization. Unconstrained and bounded constrained optimization of multivariate functions (L-BFGS-B, Truncated Newton and Simplex methods).   Math.NET Numerics http://numerics.mathdotnet.com/ free an open source numerical library - includes special functions, linear algebra, probability models, random numbers, interpolation, integral transforms. A merger of dnAnalytics with Math.NET Iridium in addition to a purely managed implementation will also support native hardware optimization. constants & special functions complex type support real and complex, dense and sparse linear algebra (with LU, QR, eigenvalues, ... decompositions) non-uniform probability distributions, multivariate distributions, sample generation alternative uniform random number generators descriptive statistics, including order statistics various interpolation methods, including barycentric approaches and splines numerical function integration (quadrature) routines integral transforms, like fourier transform (FFT) with arbitrary lengths support, and hartley spectral-space aware sequence manipulation (signal processing) combinatorics, polynomials, quaternions, basic number theory. parallelized where appropriate, to leverage multi-core and multi-processor systems fully managed or (if available) using native libraries (Intel MKL, ACMS, CUDA, FFTW) provides a native facade for F# developers

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• How to find domain registrar and DNS hosting with good DNSSEC support?

  - by rsp

  Simplified problem I want to buy a domain and make a website that is fully secured with DNSSEC. Background I've been hearing about the insecurity of DNS for years. I've watched all of the talks by Dan Kaminsky and others from DNS exploits to The future of DNS Security Panel. I knew that using DNS without security is a disaster waiting to happen. I followed the development of the DNSSEC standard. I celebrated the key signing ceremony. Everything was on the right track to finally have a secure DNS system in place. And now more than 2 years later I wanted to just do what everyone said I should do: use DNSSEC for a new domain. So I need a domain registrar and a DNS hosting service that supports DNSSEC. Surprisingly it is not that easy to even find out who does support DNSSEC. It was actually much easier to find info on DNSSEC two years ago when everyone was going to support DNSSEC Real Soon Now but now years passed and I hardly see any progress done. I just hope that I was just looking in the wrong places and someone here will explain all of the doubts. I hope that other people who want to have a secure website will also find this question useful. What is needed registrar and DNS servers with full DNSSEC support for .com domains What is not needed IPv6 support Web hosting anything more What I found out so far Go Daddy offers Premium DNS service for additional $36 per year that lets you "Secure up to 5 domains with DNSSEC". easyDNS has DNSSEC available in Beta across all service levels (you need to enable the "beta" flag in configuration) but it doesn't seem to be production ready and judging from the lack of updates it isn't a feature of highest priority (the last update from March 2011 on the easyDNS blog). Name.com - according to The Register (US domain registrar does IPv6, DNSSEC) it has DNSSEC support since 2010 but right now (October 2012) I couldn't find anything related to DNSSEC on their website. Dynadot that is very often recommended doesn't support DNSSEC Namecheap that is also often recommended doesn't support DNSSEC. The support answer from 2011 suggested that it was being added but in 2012 still no ETA is given to customers. DynDNS was supposed to support DNSSEC, I found a link explaining DNSSEC support but it gives 404 Not Found page and offers a search box - when searching for DNSSEC I get "No results were found for your query." GKG was recommended online for DNSSEC support but it's hard to find any information on the level of DNSSEC support - there is a brief explanation on what is DNSSEC and how to sign Delegation Signer records in their FAQ but no information about the level of actual support can be found. Ask Slashdot: Which Registrars Support DNSSEC? from July 2011 - Answers list Go Daddy, DynDNS, GKG, Name.com as registrars that support DNSSEC but: see above. Related questions How to find web hosting that meets my requirements? What is needed to add DNSSEC to my site? DNS hosting better managed by Domain provider or Hosting provider? Registrar with good security, DNS hosting, and DNSSEC and IPv6 resolvers? In no. 1 no one is ever mentioning DNS at all. In no. 2 answers only mention the .se TLD, there are very few answers and they seem very outdated. In no. 3 one answer says "On projects that demand higher security, I might look for a web host that supports DNSSEC" but no more information is provided. The only relevant answers are in no. 4 where easyDNS is recommended by someone who has never used them personally. Meanwhile, as of October 2012, the support of DNSSEC is described as "in beta" on the easyDNS feature list. Another one recommends SiteGround but searching their site for DNSSEC returns no results. Other answers recommend web hosting providers that don't meet the requirement of DNSSEC support. Also the question mentioned above lists 9 very specific requirements other than only DNSSEC (like eg. HTTP-only login cookies, two-factor authentications, no DNS record limits, DNS statistics of queries/day, audit trails etc.) which might have excluded many possible recommendations if one is only interested in DNSSEC support. Conclusions I thought that by the end of 2012 the support of DNSSEC among domain registrars and DNS providers would be nearly universal. I am shocked that the support seems virtually nonexistent. Is this a result of some serious problems with the DNSSEC adoption? Or is it just not a hot topic and no one bothers anymore? According to the DNSSEC Scoreboard roughly about 0.1% of .com domains support DNSSEC. Could that be caused by the lack of DNSSEC support among registrars and DNS providers, is the information too hard to find or maybe no one cares? There is even no "dnssec" tag here. Questions The information is surprisingly hard to find. That is why I am asking for first-hand experience and personal recommendations. Has anyone here actually set up a website with DNSSEC, from the domain registration to the configuration of DNS servers? Can anyone recommend any of the registrars mentioned above? Can anyone recommend any registrar not mentioned above?

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• Messaging Systems – Handshaking, Reconciliation and Tracking for Data Transparency

  - by Ahsan Alam

  As many corporations build business partnerships with other organizations, the need to share information becomes necessary. Large amount of data sharing using snail mail, email and/or fax are quickly becoming a thing of the past. More and more organizations are relying heavily on Ftp and/or Web Service to exchange data. Corporations apply wide range of technologies and techniques based on available resources and data transfer needs. Sometimes, it involves simple home-grown applications. Other times, large investments are made on products like BizTalk, TIBCO etc. Complexity of information management also varies significantly from one organizations to another. Some may deal with handful of simple steps to process and manage shared data; whereas others may rely on fairly complex processes with heavy interaction with internal and external systems in order to serve the business needs. It is not surprising that many of these systems end up becoming black boxes over a period of time. Consequently, people and business start to rely more and more on developers and support personnel just to extract simple information adding to the loss of productivity. One of the most important factor in any business is transparency to data irrespective of technology preferences and the complexity of business processes. Not knowing the state of data could become very costly to the business. Being involved in messaging systems for some time now, I have heard the same type of questions over and over again. Did we transmit messages successfully? Did we get responses back? What is the expected turn-around-time? Did the system experience any errors? When one company transmits data to one or more company, it may invoke a set of processes that could complete in matter of seconds, or it could days. As data travels from one organizations to another, the uncertainty grows, and the longer it takes to track uncertain state of the data the costlier it gets for the business, So, in every business scenario, it's extremely important to be aware of the state of the data.   Architects of messaging systems can take several steps to aid with data transparency. Some forms of data handshaking and reconciliation mechanism as well as extensive data tracking can be incorporated into the system to provide clear visibility to the data. What do I mean by handshaking and reconciliation? Some might consider these to be a single concept; however, I like to consider them in two unique categories. Handshaking serves as message receipts or acknowledgment. When one transmits messages to another, the receiver must acknowledge each message by sending immediate responses for each transaction. Whenever we use Web Services, handshaking is often achieved utilizing request/reply pattern. Similarly, if Ftp is used, a receiver can acknowledge by dropping messages for the sender as soon as the files are picked up. These forms of handshaking or acknowledgment informs the message sender and receiver that a successful transaction has occurred. I have mentioned earlier that it could take anywhere from a few seconds to a number of days before shared data is completely processed. In addition, whenever a batched transaction is used, processing time for each data element inside the batch could also vary significantly. So, in order to successfully manage data processing, reconciliation becomes extremely important; otherwise it may result into data loss or in some cases hefty penalty. Reconciliation can be done in many ways. Partner organizations can share and compare ad hoc reports to achieve reconciliation. On the other hand, partners can agree on some type of systematic reconciliation messages. Systems within responsible parties can trigger messages to partners as soon as the data process completes.   Next step in the data transparency is extensive data tracking. Some products such as BizTalk and TIBCO provide built-in functionality for data tracking; however, built-in functionality may not always be adequate. Sometimes additional tracking system (or databases) needs to be built in order monitor all types of data flow including, message transactions, handshaking, reconciliation, system errors and many more. If these types of data are captured, then these can be presented to business users in any forms or fashion. When business users are empowered with such information, then the reliance on developers and support teams decreases dramatically.   In today's collaborative world of information sharing, data transparency is key to the success of every business. The state of business data will constantly change. However, when people have easier access to various states of data, it allows them to make better and quicker decisions. Therefore, I feel that data handshaking, reconciliation and tracking is very important aspect of messaging systems.

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