This is now a complete media platform for synchronized content from Internet (MRSS, iTunes) as well as private sources with our integration Cloud support out of the box for Amazon S3.

Here is one of the framework generated experiences (you can do your own but not in this demo) which transforms the Apple Movie Trailers content:

Or click here to go direct:

http://media.tangentux.com/index.htm

Adobe has no reason to ignore Silverlight now…They do that at their own peril and eventual harm.

We will have a free version of this media center environment (yes indeed it is a lot like Windows Media Center, only completely built for Internet content). The demo above shows off some Deep Zoom integration, as well as some intelligent playback optimized for quality over M4v, MP4, and associated file types.

There is also a large demo with tons of smooth streaming content. Let me know if your interested.

del.icio.us Tags: adobe,f4v,flash video,Flex,flv,RIA,SilverLight,silverlight 3,silverlight 3 beta,silverlight adobe,Video

Technorati Tags: adobe,f4v,flash video,Flex,flv,RIA,SilverLight,silverlight 3,silverlight 3 beta,silverlight adobe,Video

This post gets you Linq access to the GAC with no fuss.

Fusion is wrapped for you so no need to understand the unmanaged stuff unless you want to. Your up and running with GAC as a new Linq to Objects source in minutes.

The Big Picture of the Project (You can skip to the next section if you just want the GAC code)

Note: The reason both the Gac and MyEnvironment IEnumerable<T> references below are different? See the reference on the bottom right of the picture into the entry point to all of it (ThisBox)?

Introduction to the Fusion  IEnumerable Wrapper

A simple case. I want to know how my GAC is broken into ‘Major Vendors’. We assume this is roughly the first part of the name. (i.e. Microsoft.System = Microsoft).

Oh yeah. Exclude the assemblies that only occur once. We are looking for the larger view here.

Here is an easy solution:

        [Fact]
        public void should_show_gac_by_vendor()
        {
            var result = from matchedAssembly in ThisBox.By<AssemblyDetail>()
                         group matchedAssembly by
                             matchedAssembly.MajorName
                             into grouping
                             where grouping.Count() > 1
                             orderby grouping.Count() descending
                             select grouping;

            var TotalSum = result.Sum(ad => ad.Count());

            Console.WriteLine("** ASSEMBLIES BY NAME WITH > 1 REGISTERED  = {0} ***", TotalSum);

            foreach (var firstGroup in result)
            {
                var groupCount = firstGroup.Count();
                Console.WriteLine("Group '{0}' Assemblies={1} Percent={2} Public Keys Used={3}",
                                    firstGroup.Key,
                                    groupCount,
                                    groupCount.ToPctString(TotalSum),
                                    firstGroup.Select(ad => ad.PublicKey).Distinct().Count()
                                    );
            }
        }

** ASSEMBLIES BY NAME WITH > 1 REGISTERED  = 664 ***

Group ‘Microsoft’ Assemblies=466 Percent=70.18% Public Keys Used=5
Group ‘DevExpress’ Assemblies=73 Percent=10.99% Public Keys Used=2
Group ‘System’ Assemblies=71 Percent=10.69% Public Keys Used=4
Group ‘Policy’ Assemblies=14 Percent=2.11% Public Keys Used=2
Group ‘FSharp’ Assemblies=11 Percent=1.66% Public Keys Used=1
Group ‘VLinq’ Assemblies=10 Percent=1.51% Public Keys Used=1
Group ‘policy’ Assemblies=6 Percent=0.9% Public Keys Used=2
Group ‘PresentationFramework’ Assemblies=5 Percent=0.75% Public Keys Used=1
Group ‘mscorcfg’ Assemblies=2 Percent=0.3% Public Keys Used=1
Group ‘WebDev’ Assemblies=2 Percent=0.3% Public Keys Used=1
Group ‘VSTADTEProvider’ Assemblies=2 Percent=0.3% Public Keys Used=1
Group ‘VsWebSite’ Assemblies=2 Percent=0.3% Public Keys Used=1

Try that with GacUtil (grin)..

C# GAC IEnumerable<Assembly> implementation

Ah yes the GAC Fusion wrapper code.  Thanks to Debasish Bose for his help here.

C# Fusion Gac Enumerable : Domain.Dot.Net Team

    /// <summary>
    /// Just to have some room to breath
    /// </summary>
    public class AssemblyDetail : AssemblyDetailBase
    {
        public AssemblyDetail(IAssemblyName currentAssembly) : base(currentAssembly) {}

        public override String FullName
        {
            get
            {
                return _fullName;
            }
        }
        public override string Version
        {
            get
            {
                return _versionString;
            }
        }
        public override int Major
        {
            get
            {
                return VersionComponent(0);
            }
        }
        public override int Minor
        {
            get
            {
                return VersionComponent(1);
            }
        }
        public override int Revision
        {
            get
            {
                return VersionComponent(2);
            }
        }
        public override int Build
        {
            get
            {
                return VersionComponent(3);
            }
        }

        public override string PublicKey
        {
            get
            {
                return _pkey;
            }
        }
        public override string MajorName
        {
            get
            {
                return _majorName;
            }
        }
        public String Name
        {
            get
            {
                return _fullName;
            }
        }

        int VersionComponent(int position)
        {
            return _version.Length <= position + 1
                           ? Convert.ToInt32(_version[position]) : 0;
        }
    }

    #region

    using System;
    using System.Runtime.InteropServices;

    #endregion

    /// <summary>
    /// Alpha - Comment and Add Regressions
    /// </summary>
    public abstract class AssemblyDetailBase
    {
        protected string _fullName;
        protected string _majorName;
        string[] _nameSplit;
        protected string _pkey;
        string _rawname;
        protected string[] _version;
        protected string _versionString;

        /// <summary>
        /// Initializes a new instance of the <see cref="AssemblyDetailBase"/> class.
        /// </summary>
        /// <param name="Current">The current.</param>
        protected AssemblyDetailBase(IAssemblyName Current)
        {
            ExtractParsedDetail(Current);
        }

        public abstract string FullName
        {
            get;
        }
        public abstract string Version
        {
            get;
        }
        public abstract int Major
        {
            get;
        }
        public abstract int Minor
        {
            get;
        }
        public abstract int Revision
        {
            get;
        }
        public abstract int Build
        {
            get;
        }
        public abstract string PublicKey
        {
            get;
        }
        public abstract string MajorName
        {
            get;
        }

        /// <summary>
        /// I do not want to persist the IAssemblyName
        /// as it might introduce a COM reference when
        /// we just can extract what we need and let it
        /// pass away into whatever...
        ///
        /// Extracts the parsed detail.
        /// </summary>
        /// <param name="Current">The current.</param>
        void ExtractParsedDetail(IAssemblyName Current)
        {
            const int stongKeyPosition = 3;
            const int versionPosition = 1;

            // Main Work Happens Here
            _fullName = GetDisplayName(Current);

            // Simply parse the ", " that seperates the full
            // name
            var _parsedDetails = _fullName.Split(new[]
                                                 {
                                                         ", "
                                                 }, StringSplitOptions.RemoveEmptyEntries);

            ExtractVersionInfo(versionPosition, _parsedDetails);
            ExtractAddition(stongKeyPosition, _parsedDetails);
        }

        void ExtractAddition(int stongKeyPosition, string[] parsedDetails)
        {
            _pkey = parsedDetails[stongKeyPosition];
            _rawname = parsedDetails[0].Trim();
            _nameSplit = _rawname.Split('.');
            _majorName = _nameSplit[0].Trim();
        }

        /// <summary>
        /// Gets the display name from the unmanaged pointer
        /// </summary>
        /// <param name="aName">A name.</param>
        /// <returns></returns>
        static string GetDisplayName(IAssemblyName aName)
        {
            var displayFlags = AssemblyNameDisplayFlags.ALL;

            uint uiLen = 0;

            string _displayAssemblyName = null;

            // Get the length
            aName.GetDisplayName(IntPtr.Zero, ref uiLen, (uint) displayFlags);

            if (uiLen > 0)
            {
                var byteBuffer = new byte[(uiLen + 1)*2];
                unsafe //turn on sunsafe in project properties
                {
                    fixed (byte* numRef1 = byteBuffer)
                    {
                        var ptr1 = new IntPtr(numRef1);
                        aName.GetDisplayName(ptr1, ref uiLen, (uint) displayFlags);
                        _displayAssemblyName = Marshal.PtrToStringUni(ptr1);
                    }
                }
            }

            return _displayAssemblyName;
        }

        /// <summary>
        /// Extracts the version info.
        /// </summary>
        /// <param name="versionPosition">The version position.</param>
        /// <param name="parsedDetails">The parsed details.</param>
        void ExtractVersionInfo(int versionPosition, string[] parsedDetails)
        {
            var versionLiteral = parsedDetails[versionPosition];
            _versionString = ToCoreVersion(versionPosition, versionLiteral);
            if (_versionString != String.Empty)
                _version = _versionString.Split('.');
        }

        /// <summary>
        /// Gets the nice clean x.x.x.x string
        /// </summary>
        /// <param name="versionPosition">The version position.</param>
        /// <param name="versionLiteral">The version literal.</param>
        /// <returns></returns>
        static string ToCoreVersion(int versionPosition, string versionLiteral)
        {
            var returnVal = String.Empty;

            if (!String.IsNullOrEmpty(versionLiteral))
            {
                var _indexOf = versionLiteral.IndexOf("=");

                if (_indexOf != -1)
                    returnVal = versionLiteral.Substring(_indexOf + versionPosition);
            }

            return returnVal;
        }
    }

#region

using System.Runtime.InteropServices;

#endregion

class GAC
{
    GAC() {}

    [DllImport("Fusion.dll", CharSet = CharSet.Auto)]
    public static extern int CreateAssemblyEnum(out IAssemblyEnum ppEnum,
                                                IApplicationContext pAppCtx,
                                                IAssemblyName pName, uint dwFlags,
                                                int pvReserved);
}

#region

using System.Runtime.InteropServices;
using System.Security;

#endregion

[SuppressUnmanagedCodeSecurity, ComImport, Guid("7C23FF90-33AF-11D3-95DA-00A024A85B51"),
 InterfaceType(1)]
public interface IApplicationContext
{
    void SetContextNameObject(IAssemblyName pName);

    void GetContextNameObject([Out] out IAssemblyName ppName);

    void Set([MarshalAs(UnmanagedType.LPWStr)] string szName, int pvValue, uint cbValue,
             uint dwFlags);

    void Get([MarshalAs(UnmanagedType.LPWStr)] string szName, [Out] out int pvValue,
             ref uint pcbValue, uint dwFlags);

    void GetDynamicDirectory([Out] out int wzDynamicDir, ref uint pdwSize);
}

#region

using System;
using System.Runtime.InteropServices;
using System.Security;
using System.Text;

#endregion

/// <summary>
/// IAssemblyName from Fusion
/// </summary>
[SuppressUnmanagedCodeSecurity, ComImport, Guid("CD193BC0-B4BC-11D2-9833-00C04FC31D2E"),
 InterfaceType(1)]
public interface IAssemblyName
{
    [PreserveSig]
    int SetProperty(uint PropertyId, IntPtr pvProperty, uint cbProperty);

    [PreserveSig]
    int GetProperty(uint PropertyId, IntPtr pvProperty, ref uint pcbProperty);

    [PreserveSig]
    int Finalize();

    [PreserveSig]
    int GetDisplayName(IntPtr szDisplayName, ref uint pccDisplayName, uint dwDisplayFlags);

    [PreserveSig]
    int BindToObject(object refIID, object pAsmBindSink,
                     IApplicationContext pApplicationContext,
                     [MarshalAs(UnmanagedType.LPWStr)] string szCodeBase, long llFlags,
                     int pvReserved, uint cbReserved, [Out] out int ppv);

    [PreserveSig]
    int GetName(ref uint lpcwBuffer,
                [Out, MarshalAs(UnmanagedType.LPWStr)] StringBuilder pwzName);

    [PreserveSig]
    int GetVersion([Out] out uint pdwVersionHi, [Out] out uint pdwVersionLow);

    [PreserveSig]
    int IsEqual(IAssemblyName pName, uint dwCmpFlags);

    [PreserveSig]
    int Clone([Out] out IAssemblyName pName);
}

#region

using System.Runtime.InteropServices;
using System.Security;

#endregion

[SuppressUnmanagedCodeSecurity, ComImport, Guid("21B8916C-F28E-11D2-A473-00C04F8EF448"),
 InterfaceType(1)]
interface IAssemblyEnum
{
    [PreserveSig]
    int GetNextAssembly([Out] out IApplicationContext ppAppCtx,
                        [Out] out IAssemblyName ppName, uint dwFlags);

    [PreserveSig]
    int Reset();

    [PreserveSig]
    int Clone([Out] out IAssemblyEnum ppEnum);
}

#region

using System.Collections;
using System.Collections.Generic;
using System.Runtime.InteropServices;

#endregion

/// <summary>
/// Fairly basic stuff once the
/// unmanaged stuff is all mapped
/// </summary>
public class GacEnumerable : IEnumerator<IAssemblyName>, IEnumerable<IAssemblyName>
{
    readonly IAssemblyEnum _enumeration;
    IAssemblyName _enumCurrentAssembly;

    GacEnumerable()
    {
        HandleCom(GAC.CreateAssemblyEnum(out _enumeration, null, null,
                                         (uint) AssemblyCacheFlags.GAC, 0));
    }

    public static GacEnumerable New
    {
        get
        {
            return new GacEnumerable();
        }
    }

    #region IEnumerable<IAssemblyName> Members

    /// <summary>
    /// Returns an enumerator that iterates through the collection.
    /// </summary>
    /// <returns>
    /// A <see cref="T:System.Collections.Generic.IEnumerator`1"/> that can be used to iterate through the collection.
    /// </returns>
    public IEnumerator<IAssemblyName> GetEnumerator()
    {
        return this;
    }

    /// <summary>
    /// Returns an enumerator that iterates through a collection.
    /// </summary>
    /// <returns>
    /// An <see cref="T:System.Collections.IEnumerator"/> object that can be used to iterate through the collection.
    /// </returns>
    IEnumerator IEnumerable.GetEnumerator()
    {
        return GetEnumerator();
    }

    #endregion

    #region IEnumerator<IAssemblyName> Members

    /// <summary>
    /// Advances the enumerator to the next element of the collection.
    /// </summary>
    /// <returns>
    /// true if the enumerator was successfully advanced to the next element; false if the enumerator has passed the end of the collection.
    /// </returns>
    /// <exception cref="T:System.InvalidOperationException">The collection was modified after the enumerator was created. </exception>
    bool IEnumerator.MoveNext()
    {
        IApplicationContext context1;
        return (0 ==
                _enumeration.GetNextAssembly(out context1, out _enumCurrentAssembly, 0));
    }

    /// <summary>
    /// Sets the enumerator to its initial position, which is before the first element in the collection.
    /// </summary>
    /// <exception cref="T:System.InvalidOperationException">The collection was modified after the enumerator was created. </exception>
    void IEnumerator.Reset()
    {
        _enumeration.Reset();
    }

    /// <summary>
    /// IAssemblyName is a Fusion interface
    /// Gets the element in the collection at the current position of the enumerator.
    /// </summary>
    /// <value></value>
    /// <returns>The element in the collection at the current position of the enumerator.</returns>
    public IAssemblyName Current
    {
        get
        {
            return _enumCurrentAssembly;
        }
    }
    // Properties
    object IEnumerator.Current
    {
        // Go to the other darn Current not this one
        get
        {
            return Current;
        }
    }
    // Fields
    public void Dispose()
    {
        _enumCurrentAssembly = null;
    }

    #endregion

    internal static void HandleCom(int hResult)
    {
        if (hResult < 0)
            Marshal.ThrowExceptionForHR(hResult);
    }
}

[Flags]
enum AssemblyCacheFlags
{
    NGenCache = 0x1,
    GAC = 0x2,
    DownloadCache = 0x4
}

[Flags]
public enum AssemblyNameDisplayFlags
{
    VERSION = 0x01,
    CULTURE = 0x02,
    PUBLIC_KEY_TOKEN = 0x04,
    PROCESSORARCHITECTURE = 0x20,
    RETARGETABLE = 0x80,
    ALL = VERSION |
        CULTURE | PROCESSORARCHITECTURE |
        PUBLIC_KEY_TOKEN | RETARGETABLE
}

More to Come

This is the tip of the iceberg so to speak. Here is a test case to show you what this now is doing and perhaps you can give us ideas where to take it. There is a lot of code. Should it be up on CodePlex? Google Code? Your Environment Variables:

       [Fact]
        public void should_show_my_env()
        {
            var sw = Stopwatch.StartNew();
            var dirs = from env in ThisBox.By<EnvironmentVariable>()
                       select env;
            foreach (var s in dirs)
            {
                Console.WriteLine(s.TypeOfEnv + " " + s.KeyName);
                Console.WriteLine("  ==>" + s.Value);
            }
            Console.WriteLine("Count : " + dirs.Count());
            Console.WriteLine("Search Took : " + sw.ElapsedMilliseconds + " ms");
            sw.Stop();
        }

Let’s join our GAC with our registry!

NOTE: we get 592 hits in 20 or so seconds…

        [Fact]
        public void should_join_policy_registry_section()
        {
            var sw = Stopwatch.StartNew();

            var result = from
                             gac in ThisBox.By<AssemblyDetail>()
                         join
                             registryKey in ThisBox.By<RegistryKey>() 

                         on gac.MajorName equals registryKey.FirstRegValue()

                         select new
                                {
                                        gac, RegVal=registryKey.FirstRegValue()
                                };

            Console.WriteLine("Count : " + result.Count());
            sw.Stop();
            foreach (var a in result)
            {
                Console.WriteLine(a.gac.MajorName + " == " + a.RegVal);
                Console.WriteLine(" ==>" + a.gac.FullName);
            }

            Console.WriteLine("Search Took : " + sw.ElapsedMilliseconds + " ms");
        }

Appendix : A Few Extension Methods we Use

  static class LinqProviderTestExtensions
    {
        /// <summary>
        /// Will perform each action for each
        /// 'row' in the included collection
        /// Each 'row' is of Type TTreeNode
        /// Will typically only be one action
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="items"></param>
        /// <param name="actions"></param>
        static internal void ForEach<T>(this IEnumerable<T> items, params Action<T>[] actions)
        {
            foreach (var t in items)
                foreach (var act in actions)
                    act.Invoke(t);
        }

        public static string FirstRegValue(this RegistryKey registryKey)
        {
            return registryKey.ValueCount > 0
                           ? (string) registryKey.GetValueNames().GetValue(0) : String.Empty;
        }

        public static double ToPercent(this int target, int total)
        {
            return target.ToPercent((double) total);
        }

        public static String ToPctString(this int target, int total)
        {
            return target.ToPercent((double) total) + "%";
        }

        public static double ToPercent(this int target, double total)
        {
            return Math.Round((target/total)*100, 2);
        }
    }

A huge Thanks:

Debasish Bose

del.icio.us Tags: Advanced C#,C# Unmanaged Wrapper,Fusion,GAC,Global Assembly Cache,IEnumerable,IEnumerator,Internals,Lambada,Linq to Gac,Linq to Objects,Machine,Registry
Technorati Tags: Advanced C#,C# Unmanaged Wrapper,Fusion,GAC,Global Assembly Cache,IEnumerable,IEnumerator,Internals,Lambada,Linq to Gac,Linq to Objects,Machine,Registry

Related Posts

Anyway here’s an idea of how the framework API is shaping up. Expect this to move dramatically toward’s Fowler’s fantastic coverage of ‘Expression Builder’.

We hope that this will evolve into a full Linq provider, and due to the XML foundation this is not all that unrealistic a goal.
 

namespace CCStatisticsTDD
{
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using CCStatistics.Domain.Api;
    using CCStatistics.Domain.Api.Interfaces;
    using NUnit.Framework;
    using Rhino.Mocks;
    using TDDViewOutputStatus;
    using ThoughtWorks.CruiseControl.Core;

    /// <summary>
    /// This is a monolitic 'Smoke Test'. There are many fine grained tests to be writtem!
    /// </summary>
    [TestFixture]
    public class MainTestFixtureBaselineSmokes : TestBase
    {
        /// <summary>
        /// Gets the mock list.
        /// </summary>
        /// <param name="mockBuildName">Name of the mock build.</param>
        /// <param name="repositoryBuildCount">The repository build count.</param>
        /// <returns></returns>
        /// Documentation Created 6/23/2008
        private static List<string> GetMockList(string mockBuildName, int repositoryBuildCount)
        {
            // Add the build name to the array tht is expected to be available for ALL builds
            // from the repositoy. Here we use 10

            return
                Enumerable.Repeat(mockBuildName + " {0}", repositoryBuildCount).Select(
                    s => String.Format(s, DateTime.Now.TimeOfDay.TotalMilliseconds/1000)).ToList();
        }

        protected override ICCStatsProject Prepare()
        {
            // We need a name for this project
            const String mockBuildName = "CCStatisticsBuildMock";

            // Simulate 100 legacy build results
            const int repositoryBuildCount = 100;

            var repository = mocks.Stub<IIntegrationRepository>();
            var buildNames = GetMockList(mockBuildName, repositoryBuildCount);

            // OK set this up to return our builds
            repository.Stub(x => x.GetBuildNames()).Return(buildNames.ToArray());

            var currentProject = mocks.Stub<ICCStatsProject>();

            currentProject.Stub(x => x.IntegrationRepository).Return(repository);
            currentProject.Stub(x => x.StatisticsForPublisher).Return(MockStats);

            currentProject.StubEx(x => x.Name, mockBuildName).
                StubEx(x => x.BuildLogDirectory, DefaultDirectory).
                StubEx(x => x.ArtifactDirectory, DefaultDirectory).
                StubEx(x => x.WorkingDirectory, DefaultDirectory).
                Stub(x => x.StatsPostPublisher).Return(InitializePublisher(currentProject));

            return currentProject;
        }

        private IMetricPublisher InitializePublisher(ICCStatsProject project)
        {
            // OK now it's interesting.. We have our own IMetricPublisher which is a stand-in for the
            // StattisticsPublisher concrete class in CruiseControl. We need to add a new overload
            // and obviously make this behave in ways it was not intended to (as we are doing all the legacy builds)
            var _statisticsPublisher = mocks.Stub<IMetricPublisher>();

            // Here we use the mock array of stats created above. This is a duplicate of StatisticsForPublisher
            // Need to look into consolodating that.
            _statisticsPublisher.Stub(x => x.ConfiguredStatistics).Return(MockStats);

            // Core Validation is Below
            _statisticsPublisher.Expect(x => x.ProcesLogFile(project.Name)).
                IgnoreArguments().Repeat.Times(project.BuildCount);

            return _statisticsPublisher;
        }

        /// <summary>
        /// NOTE: This is a FULL CYCLE Mock Smoke test. We need many more finely grained
        /// tests. This is just to ensure all is well in the application. Each subcomponent
        /// will need to have tests added as this evolves. In the mean time this works
        /// well to ensure we fundamentally work and this is called from OUR BuildServer
        /// (how META is that?) to ensure this is working.
        /// This should be your first stop to undersand this code
        /// </summary>
        [Test]
        public void ShouldSmokeTestProjectAPI()
        {
            using (mocks.Record())
                Assert.IsTrue(ForStatistics.RefreshValues(MockTDDView.New, Prepare()));
        }
    }

    public static class MockExtensions
    {
        /// <summary>
        /// Stubs the type defined
        /// </summary>
        /// <typeparam name="TType">The type of the type.</typeparam>
        /// <param name="currentProject">The current project.</param>
        /// <param name="funcMock">The func mock.</param>
        /// <param name="returnString">The return string.</param>
        /// <returns></returns>
        /// Documentation Created 6/20/2008
        public static TType StubEx<TType>(this TType currentProject, Func<TType, String> funcMock,
                                          String returnString)
            where TType : class, ICCStatsProject
        {
            currentProject.Expect(funcMock).Return(returnString).Repeat.Any();
            return currentProject;
        }
    }
}

Keep in mind, this post is not focused on DSL topics (one any developer cannot really afford to miss now), so one could debate the merits of the link I make. My argument is this:

My definition of a DSL is very simply :

A Domain Specific Language is a way, typically using a combination of visual and textual methods, or just textual, to solve a limited but typically non-trivial set of problems. It is typically a smaller stand-alone ‘language’ or language-extension to a larger more horizontal language such as C# (the point I make here is C# has evolved to allow you to expand C# with DSLs you write in C#. This is very different the the DSL Toolkit and I have never had this opinion until I finally got to be immersed deeply in functional style programming enhancements to C# and the ease of extending just about any API with extensions..

I continue the discussion of what a DSL is here. I will be adding to this section of the site over time but if you just want the listed info, no need to go on a tangent now.

Now that new .NET 3.5 C# 3.0 features are allowing us to make the Framework API of .NET work in ways not present ‘out of the box’ the scope of what is possible can be deep and broad.

Part 1 : The DSL Perspective – A Real Example

I’ll use a project we are working on now, which is quite specifically aimed to

• Minimize the configuration overhead of using an Inversion of Control container
• Provide the benefit of ‘provider/container’ independence
• Allow the consumer to change ‘container provider’ vendors with a simple change in ‘meta configuration’

In other words, we are trying to create an abstraction on top of an abstraction, as we believe this particular area is now mature enough (and indeed this is how software engineering historically more then not progresses over time) to do so.

This project has no intention of BEING an inversion of control container nor a dependency injector, rather its aim is to allow people to make use of these critical concepts in much easier ways while eliminating hesitation related to provider lock-in.

It’s no secret we are massive fans of the work of the Castle Project and they are indeed the first ‘plug-in’ adapter we are on schedule to deliver. However the architecture (something this post is NOT trying to explain) of our solution models the DOMAIN of this area, and is not specific to any particular offering (although to be blunt I would say if any bias existed it would be from the conceptual framework that exists now in the Windsor Container/MicroKernal trunk).

A domain specific example

In the area of ASP.NET one technique for loading our solution into memory is via the IHttpModule implementation we provide. Here is what the custom global.asax.cs code looks like:

public abstract class IntegrationPoint : HttpApplication, IDomainApplication {

private static IZeroConfigDI _container;

/// <summary>
/// Executes custom initialization code after
/// all event handler
/// modules have been added.
/// Also acquire a reference to the HttpModule
/// for IoC / DI if present as a module
/// </summary>
 public override void Init() {        

The interesting areas which are not provided by Microsoft include:

1. IDomainApplication interface
2. IZeriConfigDI Interface static reference
3. Modules.GetIoCModule()

The first two have more to do with our solution then the topic of this post, so I’ll focus on #3.

As this code is inside the HttpApplication, we have access to the Modules property which is read-only. Here is the documentation:

Your first reaction if your familiar with this collection is that it does not have anything even close to the GetIoCModule() method we are calling above.

Indeed this is our ‘domain specific’ extension to the .NET Framework API (one of many for this solution).

Here is the implementation of this ‘DSL’ extension:

/// <summary>
/// Provides ‘DSL specific’ extensions to the ASP.NET environment for
/// the IoC Zero Config environment which is not new (after all this becomes a static)
/// </summary>
/// The entire point for extension methods is ‘Fluency in API’ as it allows ‘shorthand’ code

public static class ZeroConfigInstanceResolver {

private const string ZeroConfigTypeString = "IoCConfigModule.IHttpModel";

 /// <summary>
/// Gets the IZeroConfigDI reference
/// (using domain specific logic and the 
/// generic logic extending the container)
/// </summary>
/// <param name="container">The container.</param>
/// <returns></returns>

public static IZeroConfigDI GetIoCModule(this HttpModuleCollection container) {

                        return
                              container.FindInstance(
                                () =>
                                        container.Get(ZeroConfigTypeString)
                                                    as IZeroConfigDI);

}

As you can see above we are very specific in our intent to add this to the HttpModuleCollection. There is nothing that interesting above except for the method call FindInstance(Func<TResult>) off the target ‘container’. This is a peek into the non-DSL related extension that represents. You might be aware that there is no such FindInstance available off the HttpModuleCollection.

One of our many goals in creating a fluent, easily used API is reducing complexity and providing very maintainable code. Here you can see the Lambada expression required to locate our service is hidden from the developer completely, yet this code is not a ‘one-off’ as we have provided both a DSL level extension in concert with a far more generic extension.

Part 2: Extending the Horizontal to Empower the Domain Specific

In looking at the HttpModuleCollection, and in our desire to facilitate other sources of resolving our module, it inherits from the abstract parent NameObjectCollectionBase.

Here is the definition of what inherits from this abstract parent:

The issue arises as this abstract base leaves it up to its concrete implementer to provide the indexer (or say Get() method) to access the object desired. Therefore a nice way to enhance this abstract type to work across all of the children is to literally pass in the method to resolve the object desired.

Part 3 : The Generic Extension

Here is the trivial extension method used to ‘open up’ the NameObjectCollectionBase and which is used above:

/// <summary>
/// Finds the instance in the NameObjectCollectionBase
/// using the Functor
/// </summary>
/// <typeparam name="TContainer">The type of the container.</typeparam>
/// <typeparam name="TResult">The type of the result.</typeparam>
/// <param name="container">The container.</param>
/// <param name="finder">The finder.</param>
/// <returns></returns>
public static TResult FindInstance<TContainer, TResult>
       (this TContainer container, Func<TResult> finder)
              where TContainer : NameObjectCollectionBase where TResult : class {

                    return finder();

}

Since we cannot abstract up the get method, we take a page from Functional Programming and literally pass in the code to execute (which we do above).

A common pattern is to expose methods like the above, but add additional versions that allow more parameters into the Func<TResult>. This is well covered well by many of the Linq references and books available.

Part 4: How this allows us to embrace deep/wide change

A simplistic example is supporting the acquisitions of our target reference (IZeroConfigDI) if it is set as ApplicationState or as an IHttpModule. We could make the design decision to allow our find method to reside literally as an extension method of our HttpApplication (and indeed this turns out to be a reasonable choice as the valid inheritors from NameObjectCollectionBase are sealed and therefore invalid as generic constraints). Here is one approach (not ideal and not our final code but this illustrates the point.) Why not offer your optimized solution?

CODE:

public abstract class IntegrationPoint : HttpApplication, IDomainApplication {

private static IZeroConfigDI _container;

/// <summary>
/// Executes custom initialization code after
/// all event handler
/// modules have been added.
/// Also acquire a reference to the HttpModule
/// or Application State
/// for IoC / DI if present
/// </summary>
public override void Init() {

                  _container = this.GetIoCModule(); base.Init();

}

And the extension on HttpApplication:

public static class ZeroConfigInstanceResolver {

private const string ZeroConfigTypeString = "IoCConfigModule.IHttpModel";

/// <summary>
/// Gets the IZeroConfigDI reference if possible (null if not found)
/// using domain specific logic and the
/// generic logic extending the container.
/// </summary>
/// <param name="container">The container.</param>
/// <returns></returns>
public static IZeroConfigDI GetIoCModule(this HttpApplication container) {

                       var modules = container.Modules;
                       var applicationState = container.Application; 
                     

                        var resultVar = modules.ToInstance(
                                   () => modules.Get(ZeroConfigTypeString)
                         )
                        ?? 
                        applicationState.ToInstance(
                                   () => applicationState.Get(ZeroConfigTypeString)
                         );

                       return resultVar as IZeroConfigDI;

}

No change is required on the extension to the FindInstance extension.

Can you see how the above can be improved?

We expand this to make the ‘rule for finding the IZeroConfigDI external. To be specific, above we have a business rule implemented that we typically would not want ‘hard coded’. In fact more then not all things considered we want this. So we do the4 following:

• Determine the Delegate signature for the business rule.
• For the above, we need as input (at a minimum) an HttpApplication instance as that is the container for the models and state, and those two items lack a shared interface or base (or we could use that).
• The signature returns (in all cases) an instance cast where it implement IZeroConfigDI to resolve this business rule.
• Therefore the business rule signature is Func<HttpApplication ,IZeroConfigDI>

NUnit 2.5 Alpha 1 Release – April 18, 2008

Note: Since this is an alpha level release, the features are not complete and some features present in this release may be removed or changed in future releases.

General

• There are no longer separate distributed packages for .NET 1.1 an 2.0. Both the binary zip and msi packages contain subdirectories for .NET 1.1 and 2.0. In the case of the msi, the user may elect to install either or both of them.

• The Visual Studio solutions and projects are now in a directory tree that is parallel to the source tree. This eliminates problems where the VS2003 and VS2005 builds were interfering with one another and makes room for adding VS2008.

• NUnit is now built using NAnt 0.86 beta 1

• The windows installer is now created using WiX 2.0.5085

Framework

• Two new attributes have been added to support passing arguments to test methods:
• TestCaseAttribute allows the programmer to specify the arguments and a number of optional parameters inline.

• DataSourceAttribute identifies a static property that will provide the arguments and other parameters.

Two new constraints have been added to permit testing of application-created paths, without requiring that they exist in the file system. The following syntax is supported:

• Is.SamePath(string)

• Is.SamePathOrUnder(string)

The DirectoryAssert class has been added, providing the following Methods:

• AreEqual(DirectoryInfo, DirectoryInfo)

• AreEqual(string, string)

• AreNotEqual(DirectoryInfo, DirectoryInfo)

• AreNotEqual(string, string)

• IsEmpty(DirectoryInfo, DirectoryInfo)

• IsEmpty(string, string)

• IsNotEmpty(DirectoryInfo, DirectoryInfo)

• IsNotEmpty(string, string)

• IsWithin(DirectoryInfo, DirectoryInfo)

• IsWithin(string, string)

• IsNotWithin(DirectoryInfo, DirectoryInfo)

• IsNotWithin(string, string)

The method Assert.Throws(Type expectedException, TestSnippet code) has been added to provide more control over tests of expected exceptions. TestSnippet is a delegate, which may of course be supplied anonymously under .NET 2.0. If the correct exception type is thrown, the actual exception is returned from the method, allowing further verification to be performed.

• The Assert.DoesNotThrow method may be used to verify that a delegate does not throw an exception.

• The Assert.Pass method allows early termination of a test with a successful result.

• The Assert.Inconclusive method allows returning the new Inconclusive result state.

NUnit now includes added funtionality in the .NET 2.0 build of the framework. The following additional features are supported:

• All Asserts and Constraints work with nullable types.

Some Asserts allow an alternate generic syntax for convenience:

• Assert.IsInstanceOf<T>(object actual);

• Assert.IsNotInstanceOf<T>(object actual);

• Assert.IsAssignableFrom<T>(object actual);

• Assert.IsNotAssignableFrom<T>(object actual);

• Assert.Throws<T>(TypeSnippet code);

The following obsolete interfaces, classes and methods have been removed:

• The IAsserter interface

• The AbstractAsserter class

• The Assertion class

• The AssertionFailureMessage class

• The old NUnit.Framework.TestCase class used for inheriting test classes

• The Assert.DoAssert() method

• Two ExpectedExceptionAttribute(Type, string) constructor

• Two ExpectedExceptionAttribute(string, string) constructor

The syntactic constructs in the SyntaxHelpers namespace have been moved to the NUnit.Framework.Syntax.CSharp namespace. The old namespace may still be used for existing classes, but will not be supported after the 2.5 release.

Core

• NUnit now allows use of static methods as tests and for SetUp, TearDown, TestFixtureSetUp and TestFixtureTearDown.

• Failures and Errors are now distinquished internally and in summary reports. Methods that are not run because they are invalid are also reported separately.

Console

• The summary report now displays Errors, Failures, Inconclusive, Ignored and Skipped tests separately. More detailed information on non-runnable tests and setup failures is provided.

• The console summary report is no longer created using a stylesheet, which renders the /transform option meaningless. The option has been removed.

Gui

• The default GUI display now uses a single tab for all text output. For users upgrading from an earlier release, the current settings are honored. If you wish to change to the new default, use the Restore Defaults button on the Text Output settings dialog.

• The final test run display shows a more detailed summary: passed tests, errors, failures, inconclusive, non-runnable, skipped and ignored.

• The status bar now displays errors and failures separately in.

• The tree display shows non-runnable tests in red and inconclusive tests in orange. Inconclusive tests are temporarily listed on the Tests Not Run tab for this alpha release.

Extensibility

• A new extension point ParameterProviders allows addins to provide data for parameterized tests.

• The following extensions are included in the nunit.core.extensions and nunit.framework.extensions assemblies:
• The MaxTime extension, which was previously a sample.

• The RowTest extension, which remains an alternative to NUnit’s native TestCase syntax.

• The XmlConstraint extension, which allows comparing two xml files

Technorati Tags: agile,NUnit,Software Engineering,TDD,C#,Fluent API

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From ReSharper’s EAP Site

I’ve been using the 4.0 EAP (pre-beta) since the first preview and it’s awesome… Rocky at times, but I’ve never lost any code (however you should use at your own risk!).

There is something very comforting in auto-creating an anonymous delegate and having it convert automagically to lambata syntax….

For example, here is a step by step from a real code sample:

C# 3.0 support

Implicitly typed locals and arrays

Fully supported, including suggestions to omit explicit type specification, Introduce Variable refactoring and context actions to convert to implicit or explicit form.

Extension Methods support

Fully supported, with Import Symbol completion (previously known as Type Name completion) after dot which can import suitable extension method and insert appropriate using directive. Analysis will suggest converting invocations from static-like to instance-like form. Context action can convert it back, and there are refactorings to convert static method of static class to Extension Method and update all call sites. There is also reverse refactoring, of course.

Object and collection initializers

Fully supported, with suggestions and context actions to fold series of statements to collection or object to initializer, if possible.

ReSharper also provides smart intellisense features in such places, like completing settable properies or displaying correct parameter information for Add method used in collection initializer.

Automatic properties

Fully supported, with context actions to convert to property with backing field and back. Analysis can show properties which are candidates for conversion. Code generation features may suggest creating automatic property in addition to property with backing field, if appropriate.

Anonymous types

Fully supported. ReSharper can search for similar anonymous types throughout the project or solution, give a name to anonymous type and replace usages, rename properties, suggest reordering properties if two anonymous types look similar and more.

Lambdas

Partially supported. By partially, it means that not all features we want there are ready. The code shouldn’t be red and intellisense should be working, but some context actions, quickfixes, analysis and such may be missing. We are actively working on those features, so as time passes ReSharper will be more and more smart about lambdas. We have conversion actions like delegate to lambda and back and some suggestions. Note, that not all features of ReSharper are lambda-aware yet, so they may fail when they happen to operate on lambdas.

LINQ

Almost supported. We import appropriate extension methods, provide intellisense, a number quickfixes, our refactorings are aware of queries. We also provide special live templates.

Partial methods

Not supported.

New and updated features

Go to Type, File, Symbol and Find Results

You can now put results of “Go to” features to find results for browsing

External Annotations

Ability to annotate external (non-source) symbols with ReSharper-specific attributes, like CanBeNull and NotNull. Note, that we standardized attribute names for better interoperability and less configuration hassle, so you may need to refactor you code a bit if you use these attributes.

Code Cleanup

Successor of Reformat Code, Optimize Usings and other code cleaning features – all in one interface with many more modules. Includes things like processing readonly fields, removing redundancies, updating file header, converting to automatic properties, replacing explicit types with vars and more. All in batch mode, so that you can instantly clean the whole project or even solution.

Plenty of new analyses

We added many more inspections in ReSharper 4. Some of them are related to C# 3.0 and deal with new language constructs. Also, there are new structure-related inspections, like “if” statement analysis, anonymous method closure analysis, and more. We also added new severity level for analysis results – Hint – which is a lot less intrusive. It does not participate in next/previous highlight navigation and is not shown on error stripe. It simply tells you: “Pssst! Take a look here, it can make your code look better.”

Complete Statement

Also known as Smart Enter, it inserts required syntax elements to complete the code you are writing. It can close parentheses as needed, add semicolon, complete constructs such as if, while, for and so on.

Completion with CamelHumps

All kinds of code completion (Symbol completion, Import Symbol Completion and Smart Completion) now supports filtering by CamelHumps, which tremendously speeds things up. E.g. if you know you have DefaultCodeCompletionManager type somewhere you just type DCCM and invoke Import symbol completion. Full type name will be inserted and using directive will be added as needed.

Refactorings

There are new refactorings related to C# 3.0 features, like “Convert Property to Automatic Property” and back, “Convert Static Method to Extension Method” and back and “Name Anonymous Type”. “Introduce Variable” is now dialogless and this improves coding flow a lot! Another great new refactoring is “Inline Method”, which can replace method call with method body at specific point or all over your code. “Method to Indexer” is a nice addition to “Method to Property” refactoring. There are also improvements in almost all refactorings, both in usability and smartness.

Recent Edits

In addition to Recent Files we created Recent Edits feature, which shows what you’ve been changing recently. If appropriate, it displays type and member the change occured in.

To-do items on identifiers and string literals

You can now configure ReSharper to search for specific patterns not only in comments, but also in string literals and identifiers. It is quite useful to set NotImplementedException pattern to have a quick access to code you have to write.

Support for solutions using different targets

ReSharper now fully supports solutions where different projects use different versions of CLR like .NET Compact Framework or Silverlight. You can now have e.g. Smart Device projects and normal projects in the same solution and all ReSharper features will work perfectly fine in this scenario.

Project References

This is more like preview of the feature which may or may not come into final bits of ReSharper 4. It can show dependencies between projects and libraries in terms of assembly references.

Live Templates Editor

We are improving usability of Live Templates editor and currently it is large work in progress. Be careful with it if you use custom templates.

Easier creation of new folders through generate (Alt+Insert shortcut)

Dozens of other features

We also have dozens of other minor features, keep track of

this tracker query for the current list.

ReSharper 4.0 EAP Notes – JetBrains.net

Not to be a terrible bore, but brush up on your Wittgenstein lately?! Ok don’t go that far just yet…(grin).

 First, a Pattern Language (P.L.) is not some academic concept, although many would like you to believe that.

	‘Software as a Service – The Pattern Language Approach’
	‘Software as a Service – The Pattern Language Approach’
	‘Software as a Service – The Pattern Language Approach’

NOTE: I take issue with the word design below… It should be far more broad in most cases, but it often gets boxed into the design aspect of a problem. I would say ‘best practices’ which brings up its own semantic mess…

A pattern language is a structured method of describing [best] good design practices within a field of expertise. It is characterized by

1. Noticing and naming the common problems [and positively executed solutions proven over time] in a field of interest [domain in my words]
2. Describing the key characteristics of effective solutions for meeting [one or more] some stated goal[s], [Often patterns are combined and are multi-faceted]
3. Helping the designer [domain stakeholder] move from problem to problem [and challenge to challenge] in a logical way, [in an attempt to reduce and even eliminate ambiguity] and allowing for many different paths through the design process.

- Wikipedia 

1. This ties in perfectly with my claim that complex software engineering is a ‘wicked problem’. If you disagree then you can stop reading, as none of my assumptions will work. However, I would love to hear your arguments since only around 20-30% of all software projects ’succeed’…. There is no doubt there is dreadful crisis which I know you know about so enough said.

If the fundamental issue here is NOT that people cannot/will not see software engineering for what it is, then what?!

Wicked Problem

FYI: This is also why your pretty much nuts to not be Agile at this point, with some critical exceptions.

OK just to get you started chew on these 10 basic characteristics and tell me how any of them and the failure of senior stakeholders to understand that indeed software fits these characteristics is likely a key systemic disaster which we see and live every day in this industry. Click here for more.

 Before I was able to ‘take this deck on the road’ which I have done now with success (and why I am revisiting this post to offer insights), I had to get the audience (I hate to call them that… The collaborators is better) knowing (for example) that SOA was not a damn bunch of web services! I had to get people understanding exactly how distributed objects and components ARE NOT THE SAME but are similar. etc. etc.

That ASMX pages in .NET are not even close to what you want to be doing, even with WSE 3.0 and ‘Contract First’ techniques (most notably the WSCF add-in from the always amazing thinktecture).

There is nothing more necessary than truth, and in comparison with it everything else has only secondary value.
This absolute will to truth: what is it? Is it the will to not allow ourselves to be deceived? Is it the will not to deceive?
One does not want to be deceived, under the supposition that it is injurious, dangerous, or fatal to be deceived.

Friedrich Nietzsche, 1890

Thanks Herr Nietzsche… None of us want that. So “Listen for the speakers intended meaning, not your perceived definition”.

In this rather philosophical vein, I offer you here an attempt at the beginnings of a unified P.L. covering many best practices we have evolved in the SOA/SaaS space.

As stated, this presentation is born from necessity as it has become almost impossible to have a meaningful conversation on many topics in this domain due to ‘definition overloading’.

This presentation not only attacks that issue, it also brings together into a cohesive pattern language Object Orientation, Distributed Objects, Components and Services while being careful to not make overly broad generalizations that would harm any SaaS initiative.

For example, it is a best practice to evolve a Domain Driven API which is (at a minimum) the core APU which your services will use to fulfil their contracts.

The presentation is here and feedback is encouraged. This also assumes you have embraced either the SCA environment (for Java development) or WCF for .NET. These are (in our guidance to clients) the only relevant implementation frameworks for strategic large scale organizational transformations to SaaS.

Otherwise in real-world terms there are not resources (developers, or the dramatically increased effort with very little benefit) available to support other approaches. Many ‘purists to the extreme’ might attempt a hand-crafted ‘build it all over again’ approach with hand-crafted contracts (typically XSDs).

As these environments support full extensibility, indeed it is incredibly rare that one of these environments will not completely address your needs. Of course there are always exceptions, but this is addresses to 95% of the market.

Due to the immaturity of this space, it is alarming how many companies believe they are not part of that 95%!! Typically they are being driven by parties (internal or external) that have motivations not in line with the business drivers.