Managed Extensibility Framework (MEF) Contrib

Reopened Issue: Provider Model - DefinitionProviderPartCatalog does not cache values unless aggregated [1943]

TheCodeJunkie — Fri, 14 Jun 2013 07:15:30 GMT

The DefinitionProviderPartCatalog does not cache any parts unless it's added to an AggregateCatalog first. This means that when the AddProviderPart metnod is called on the CompositionContainer it will fail with an exception. The reason for this is that the method will try to retreive a ProviderComposablePartDefinition for the object instance and the cache will be empty!

New Post: Constructor parameter injection

omar_gamil — Sun, 26 May 2013 07:58:57 GMT

Hello,

Can customize AppStart_MefContribMVC3 to add custom exported values ?

I have this class

    [Export(typeof(IUserRepository))]
    public class UserRepository : GenericRepository<User>, IUserRepository
    {
        [ImportingConstructor]
        public UserRepository(string connectionString)
            : base(connectionString)
        {

        }
    }
}

how can I add this in AppStart_MefContribMVC3 ?

ComposeExportedValue("connectionString", "connection string value");

Thank you

Closed Issue: Provider Model - DefinitionProviderPartCatalog does not cache values unless aggregated [1943]

TheCodeJunkie — Thu, 16 May 2013 09:39:41 GMT

New Comment on "Introduction to the Managed Extensibility Framework"

praseodeveloper — Sun, 07 Apr 2013 16:55:17 GMT

Nice introduction to MEF. Having a good time using it at work. :)

New Post: MefContrib: Interception.Unity + Integration.Unity

rickyno — Wed, 27 Mar 2013 20:55:41 GMT

Hi
I'm trying to achieve something but can't get my head around how to do it. Basically I have multiple interfaces implementations marked with a custom Export attribute, so they get picked up by MEF, and the catalog in which they are is registered in a UnityContainer. The constructor of these implementations have the ImportingConstructor so unity can inject the parameters when MEF creates a requested part. This bit works just fine.

My problem is, I need to setup interception on certain types in the catalog, and I'm using Unity interception and this cannot be changed in my scenario. Here how it was configured before using MEF to load them:

unityContainer.RegisterType<IAuthenticationService, AuthenticationService>().Configure<Interception>().SetInterceptorFor<IAuthenticationService>(new InterfaceInterceptor());

My new code to load these using MEF:

DirectoryCatalog directoryCatalog = new DirectoryCatalog(".");
FilteredCatalog servicesCatalog = new FilteredCatalog( /* filtering on a metadata of the custom export attribute */ );

// servicesCatalog is properly populated at this point
// TODO: need to setup interception, as in the previous code block, on the servicesCatalog parts, without knowing the interface and implementation names (IAuthenticationService, AuthenticationService) except by looking at the ExportDefinitions. So I'm Stuck Here!

unityContainer.EnableCompositionIntegration();
unityContainer.RegisterCatalog(servicesCatalog);

// resolving a known interface here, loaded from MEF catalog above, works perfectly fine, Unity injects construct parameters to that instance being constructed by MEF, so my 2-way integration is fine.

But now that all I have is a FilteredCatalog with ComposableParts, I simply don't know how to adapt my interception code using MefContrib.Interception.Unity, and I can't seem to find any documentation or samples on this matter.

Any help would greatly be appeciated.

New Comment on "Unity Integration"

barakbbn — Sun, 24 Mar 2013 11:15:58 GMT

Does it support Open generics? Since as far as I tried, both using unity open-generic registration: ... RegisterType(typeof(IConfiguration<>), typeof(FileBasedConfiguration<>)) and using MEFContrib open-generic solution (GenericCatalog & GenericContractRegistryBase) it didn't work. (inject to ImportingConstructor in this case) Without the MEF-unity integration, each open-generic solution works fine (but without the benefits on Unity+MEF, of course) Thanks

New Post: MVC4

JayKnowsit — Thu, 01 Nov 2012 05:21:14 GMT

Is there Mefcontrib.MVC4? Or can some explain how I can use the Mefcontrib.MVC3 for the MVC4 application?

New Post: MEF Exported class with Unity dependency not composed

bstabile — Thu, 18 Oct 2012 19:08:34 GMT

Robert,

It this something like what you want?

(Note that the CompositionContainer is resolved from Unity BEFORE ComposeParts is called)

    [TestClass]
    public class MefUnityIntegrationTests
    {

... 
        [TestMethod]
        public void BasicMefUnityIntegrationTest()
        {
            var unityContainer = new UnityContainer();
            TypeRegistrationTrackerExtension.RegisterIfMissing(unityContainer);
 
            unityContainer.RegisterType<IUnityThing, UnityThing>();
 
            var catalog = new AssemblyCatalog(typeof(MefUnityIntegrationTests).Assembly);
            unityContainer.RegisterCatalog(catalog);
            var mefContainer = unityContainer.Resolve<CompositionContainer>();
            mefContainer.ComposeParts(this);
 
 
 
            foreach (var plugin in MyPlugins)
            {
                this.TestContext.WriteLine("Plugin.Name = {0}  Plugin.Thing.Name = {1}", plugin.Name, plugin.Thing.Name); 
            }
        }
 
        [ImportMany(typeof(IPlugin))]
        public List<IPlugin> MyPlugins { get; set; }
 
    }
 
    public interface IPlugin
    {
        string Name { get; }
        IUnityThing Thing { get; set; }
    }
 
    [Export(typeof(IPlugin))]
    public class PluginA : IPlugin
    {
        public string Name { get { return "PluginA"; } }
 
        [Import]
        public IUnityThing Thing { get; set; }
    }
 
    [Export(typeof(IPlugin))]
    public class PluginB : IPlugin
    {
        public string Name { get { return "PluginB"; } }
 
        [Import]
        public IUnityThing Thing { get; set; }
    }
 
    public interface IUnityThing
    {
        string Name { get; }
    }
 
    public class UnityThing : IUnityThing
    {
        public string Name { get { return "UnityThing"; } }
    }

In any case, this particular example works for me, producing the following output...

Plugin.Name = PluginA  Plugin.Thing.Name = UnityThing
Plugin.Name = PluginB  Plugin.Thing.Name = UnityThing

Regards,

Ben

Source code checked in, #79962

Project Collection Service Accounts — Mon, 01 Oct 2012 21:14:48 GMT

Upgrade: New Version of LabDefaultTemplate.xaml. To upgrade your build definitions, please visit the following link: http://go.microsoft.com/fwlink/?LinkId=254563

Source code checked in, #79961

Project Collection Service Accounts — Mon, 01 Oct 2012 21:08:39 GMT

Checked in by server upgrade

New Post: MEF Exported class with Unity dependency not composed

bertnz — Tue, 10 Jul 2012 06:11:03 GMT

Hi all,

I am quite new to this so I may be doing something real dumb but here goes.

Have been using a MEF directory cataglog and a CompositionContainer to populate a list of objects and runtimes (based on the components in my directory.

It goes something like this

[ImportMany(typeof(IPlugin))]
public List<IPlugin> MyPlugins { get; set; }

var catalog = new DirectoryCatalog("PluginFolder");
var container = new CompositionContainer(catalog);
container.ComposeParts(this);

It was working perfectly fine and populating my MyPlugins property with my 2 plugins.

I have since added unity into my solution and have add a dependency to one of my plugin classes. As soon as I do this it stops appearing in my list of plugins. No error occurs - it is like my plugin has vanished as soon as it has the dependency added.

I have registered my catalog against my unity container (which has already been fully registered/configured)

var catalog = new DirectoryCatalog("PluginFolder");
unityContainer.RegisterCatalog(catalog);
var container = new CompositionContainer(catalog);
container.ComposeParts(this);

The plugin itself has its Unity-owned dependency specified like so

  [Import]
  public IUnityHostedThing MyThing { get; set; }

I have also tried the constructor injection like so

[ImportingConstructor]
public PluginA(IUnityThing thing)
{
    this.Mything = thing;
}

Neither approach works and either way the class no longer gets returned by the composition container stuff.

Any ideas? I haven't seen a good up to date example of this working with any actual implementations online - are there any?

cheers,
Robert

Commented Issue: Add Parameter to RegisterCatalog to add UNIQUE parts [10977]

montijr2007 — Thu, 05 Jul 2012 18:53:48 GMT

A suggestion that I believe would be beneficial to a lot of developers, would be to add the ability to register the parts of the Aggregate catalog, ignoring duplicates.

The issue is, that when I register my exported parts, I get duplicate registrations for the same Export - leading me to the exception, "ImportCardinalityMismatchException", when I try to Resolve<T>().

There isn't an easy work around that I have found and I believe it would be nice to have as part of this package.

Code sample below:

private static void RegisterAssemblies(string assemblyPath, string searchPattern)
{
string[] directories = Directory.GetDirectories(assemblyPath, "Debug", SearchOption.AllDirectories);
var exportedParts = new AggregateCatalog();

foreach (string directory in directories)
{
var assemblyCatalog = new DirectoryCatalog(directory);
exportedParts.Catalogs.Add(assemblyCatalog);
}

_container.RegisterCatalog(exportedParts);
}
Comments: ** Comment from web user: montijr2007 **

Here is what I believe would work- Add this to the UnityContainerExtensions source code for the "RegisterCatalog" method:

public static void RegisterCatalog(this IUnityContainer unityContainer, ComposablePartCatalog catalog)
{
lock (unityContainer)
{
var compositionIntegration = EnableCompositionIntegration(unityContainer);
compositionIntegration.Catalogs.Add(catalog);

IEnumerable<ComposablePartCatalog> parts = compositionIntegration.Catalogs.Distinct().ToList();
compositionIntegration.Catalogs.Clear();

foreach (var part in parts)
{
compositionIntegration.Catalogs.Add(part);
}

}
}

Created Issue: Add Parameter to RegisterCatalog to add UNIQUE parts [10977]

montijr2007 — Thu, 05 Jul 2012 17:10:24 GMT

New Comment on "Documentation & Features"

mahatab — Wed, 27 Jun 2012 06:11:39 GMT

Is there any document for MEFContrib, that includes all features and how to use that? That may help us as a reference.

Created Issue: Generic Export With Method Export [10747]

hendryluk — Wed, 09 May 2012 07:11:35 GMT

Given this import:
provider.GetExportedValues<Foo<int>>();

This works:
[Export]
public class Foo<T>
{
public void Blah()
{
}
}
(Returns 1 export for Foo<int>).

This does not work:
[Export]
public class Foo<T>
{
[Export]
public void Blah()
{
}
}
(Returns 0 export for Foo<int>)

I understand that the method export here seems pointless since it can't possibly be imported with out-of-the-box catalogue, but this should be fine since I'll be creating my own custom catalog to handle this method export. What i can't understand is why Foo<int> does not return any export at all.

New Post: New NuGet Version, Please? :)

MichaelDBang — Tue, 28 Feb 2012 21:29:12 GMT

Can we get a new version of this library in NuGet that has updated dependencies on Unity and also an assembly version for Silverlight? :)

Thank you,

Michael

New Post: GenericContractTypeMapping is a sealed class so it's not possible to derive

pwlodek — Sat, 18 Feb 2012 19:07:40 GMT

Can you please provide sample solution we can both work on ?

New Post: GenericContractTypeMapping is a sealed class so it's not possible to derive

kavand — Thu, 16 Feb 2012 10:46:00 GMT

@Piotr I follow that blog post for my MVC3 application. But I get this error:

The IControllerFactory 'MefContrib.Web.Mvc.CompositionControllerFactory' did not return a controller for the name 'Home'

Can you guide me please?

New Post: MefContrib.MVC3 and Lazy imports on controllers

maartenba — Thu, 16 Feb 2012 08:21:30 GMT

Can you post a small repro project so I can investigate?

New Post: MefContrib.MVC3 and Lazy imports on controllers

kavand — Thu, 16 Feb 2012 07:08:31 GMT

I get same error too. Can everybody help please???