Expose singleton GitHub ExportProvider via MEF

Author: jcansdale

src/GitHub.VisualStudio.16/CompositionServices.cs

@@ -17,12 +17,43 @@
 using Microsoft.VisualStudio.Shell;
 using Microsoft.VisualStudio.Threading;
 using Rothko;
+using static Microsoft.VisualStudio.Composition.NetFxAdapters;
+using ExportProvider = System.ComponentModel.Composition.Hosting.ExportProvider;
 
 namespace GitHub.VisualStudio
 {
+    [Export]
     public class CompositionServices
     {
-        public CompositionContainer CreateVisualStudioCompositionContainer(ExportProvider defaultExportProvider)
+        readonly ExportProvider defaultExportProvider;
+        ExportProvider exportProvider;
+
+        public CompositionServices()
+        {
+        }
+
+        [ImportingConstructor]
+        public CompositionServices(Microsoft.VisualStudio.Composition.ExportProvider defaultExportProvider)
+        {
+            this.defaultExportProvider = defaultExportProvider.AsExportProvider();
+        }
+
+        public ExportProvider GetExportProvider()
+        {
+            return exportProvider = exportProvider ?? CreateCompositionContainer();
+        }
+
+        CompositionContainer CreateCompositionContainer()
+        {
+            if (defaultExportProvider is ExportProvider exportProvider)
+            {
+                return CreateVisualStudioCompositionContainer(exportProvider);
+            }
+
+            return CreateOutOfProcCompositionContainer();
+        }
+
+        static CompositionContainer CreateVisualStudioCompositionContainer(ExportProvider defaultExportProvider)
         {
             var compositionContainer = CreateCompositionContainer(defaultExportProvider);
 
@@ -34,7 +65,7 @@ public CompositionContainer CreateVisualStudioCompositionContainer(ExportProvide
             return compositionContainer;
         }
 
-        public CompositionContainer CreateOutOfProcCompositionContainer()
+        static CompositionContainer CreateOutOfProcCompositionContainer()
         {
             var compositionContainer = CreateCompositionContainer(CreateOutOfProcExports());
 

src/GitHub.VisualStudio.16/InBoxExtensionServices.cs

@@ -72,14 +72,14 @@ async Task<CodeContainer> RunAcquisitionAsync(IProgress<ServiceProgressData> dow
         static async Task<CloneDialogResult> ShowCloneDialogAsync(IComponentModel componentModel,
             IProgress<ServiceProgressData> downloadProgress, CancellationToken cancellationToken, string url = null)
         {
-            var compositionServices = new CompositionServices();
-            var compositionContainer = compositionServices.CreateVisualStudioCompositionContainer(componentModel.DefaultExportProvider);
+            var compositionServices = componentModel.DefaultExportProvider.GetExportedValue<CompositionServices>();
+            var exportProvider = compositionServices.GetExportProvider();
 
-            var dialogService = compositionContainer.GetExportedValue<IDialogService>();
+            var dialogService = exportProvider.GetExportedValue<IDialogService>();
             var cloneDialogResult = await dialogService.ShowCloneDialog(null, url);
             if (cloneDialogResult != null)
             {
-                var repositoryCloneService = compositionContainer.GetExportedValue<IRepositoryCloneService>();
+                var repositoryCloneService = exportProvider.GetExportedValue<IRepositoryCloneService>();
                 await repositoryCloneService.CloneOrOpenRepository(cloneDialogResult, downloadProgress, cancellationToken);
                 return cloneDialogResult;
             }

src/GitHub.VisualStudio.16/Sync/PublishSection.cs

@@ -10,9 +10,7 @@
 using GitHub.ViewModels.TeamExplorer;
 using GitHub.VisualStudio;
 using Microsoft.TeamFoundation.Controls;
-using Microsoft.VisualStudio.Composition;
 using ReactiveUI;
-using ExportProvider = System.ComponentModel.Composition.Hosting.ExportProvider;
 
 
 namespace Microsoft.TeamExplorerSample.Sync
@@ -23,7 +21,7 @@ namespace Microsoft.TeamExplorerSample.Sync
     [TeamExplorerSection(SectionId, TeamExplorerPageIds.GitCommits, Priority)]
     public class PublishSection : TeamExplorerBaseSection
     {
-        readonly ExportProvider defaultExportProvider;
+        readonly CompositionServices compositionServices;
 
         public const string SectionId = "35B18474-005D-4A2A-9CCF-FFFFEB60F1F5";
         public const int Priority = 4;
@@ -32,9 +30,9 @@ public class PublishSection : TeamExplorerBaseSection
         readonly Guid GitHubPublishSectionId = new Guid("92655B52-360D-4BF5-95C5-D9E9E596AC76");
 
         [ImportingConstructor]
-        public PublishSection(VisualStudio.Composition.ExportProvider defaultExportProvider)
+        public PublishSection(CompositionServices compositionServices)
         {
-            this.defaultExportProvider = defaultExportProvider.AsExportProvider();
+            this.compositionServices = compositionServices;
 
             this.Title = "Publish to GitHub";
             this.IsExpanded = true;
@@ -82,7 +80,7 @@ public override void Initialize(object sender, SectionInitializeEventArgs e)
 
         void ShowPublishDialog()
         {
-            var exportProvider = GetExportProvider();
+            var exportProvider = compositionServices.GetExportProvider();
 
             var factory = exportProvider.GetExportedValue<IViewViewModelFactory>();
             var viewModel = exportProvider.GetExportedValue<IRepositoryPublishViewModel>();
@@ -112,13 +110,6 @@ void ShowPublishDialog()
             SectionContent = view;
         }
 
-        ExportProvider GetExportProvider()
-        {
-            var compositionServices = new CompositionServices();
-            var compositionContainer = compositionServices.CreateVisualStudioCompositionContainer(defaultExportProvider);
-            return compositionContainer;
-        }
-
         void Section_PropertyChanged(object sender, PropertyChangedEventArgs e)
         {
             switch (e.PropertyName)

src/GitHub.VisualStudio.TestApp/MainWindow.xaml.cs

@@ -71,11 +71,13 @@ async Task CloneOrOpenRepositoryAsync()
         CompositionContainer CreateCompositionContainer()
         {
             var compositionServices = new CompositionServices();
-            var compositionContainer = compositionServices.CreateOutOfProcCompositionContainer();
+            var exportProvider = compositionServices.GetExportProvider();
 
-            var gitHubServiceProvider = compositionContainer.GetExportedValue<IGitHubServiceProvider>();
+            var compositionContainer = new CompositionContainer(exportProvider);
+            var gitHubServiceProvider = exportProvider.GetExportedValue<IGitHubServiceProvider>();
             var externalShowDialogService = new ExternalShowDialogService(gitHubServiceProvider, this);
             compositionContainer.ComposeExportedValue<IShowDialogService>(externalShowDialogService);
+
             return compositionContainer;
         }
     }