add bcl.asyncinterfaces

Author: BrennanConroy

eng/Dependencies.props

@@ -42,6 +42,7 @@ and are generated based on the last package release.
     <LatestPackageReference Include="Microsoft.AspNetCore.Testing" Version="$(MicrosoftAspNetCoreTestingPackageVersion)" />
     <LatestPackageReference Include="Microsoft.Azure.KeyVault" Version="$(MicrosoftAzureKeyVaultPackageVersion)" />
     <LatestPackageReference Include="Microsoft.Azure.Storage.Blob" Version="$(MicrosoftAzureStorageBlobPackageVersion)" />
+    <LatestPackageReference Include="Microsoft.Bcl.AsyncInterfaces" Version="$(MicrosoftBclAsyncInterfaces)" />
     <LatestPackageReference Include="Microsoft.Build.Framework" Version="$(MicrosoftBuildFrameworkPackageVersion)" />
     <LatestPackageReference Include="Microsoft.Build.Utilities.Core" Version="$(MicrosoftBuildUtilitiesCorePackageVersion)" />
     <LatestPackageReference Include="Microsoft.CodeAnalysis.Common" Version="$(MicrosoftCodeAnalysisCommonPackageVersion)" />

eng/Version.Details.xml

@@ -293,6 +293,10 @@
       <Uri>https://github.com/aspnet/Extensions</Uri>
       <Sha>2d3e9b5b4c0cf8cc76c0861980ad82e5ea23429e</Sha>
     </Dependency>
+    <Dependency Name="Microsoft.Bcl.AsyncInterfaces" Version="1.0.0-preview7.19309.4" CoherentParentDependency="Microsoft.NETCore.App">
+      <Uri>https://github.com/dotnet/corefx</Uri>
+      <Sha>46d9f33d96a1db41a9634b84dd68256db2eeed4f</Sha>
+    </Dependency>
     <Dependency Name="Microsoft.CSharp" Version="4.6.0-preview7.19309.4" CoherentParentDependency="Microsoft.NETCore.App">
       <Uri>https://github.com/dotnet/corefx</Uri>
       <Sha>46d9f33d96a1db41a9634b84dd68256db2eeed4f</Sha>

eng/Versions.props

@@ -64,6 +64,7 @@
     <MicrosoftNETCoreAppPackageVersion>3.0.0-preview7-27809-08</MicrosoftNETCoreAppPackageVersion>
     <NETStandardLibraryRefPackageVersion>2.1.0-preview7-27809-08</NETStandardLibraryRefPackageVersion>
     <!-- Packages from dotnet/corefx -->
+    <MicrosoftBclAsyncInterfaces>1.0.0-preview7.19309.4</MicrosoftBclAsyncInterfaces>
     <MicrosoftCSharpPackageVersion>4.6.0-preview7.19309.4</MicrosoftCSharpPackageVersion>
     <MicrosoftWin32RegistryPackageVersion>4.6.0-preview7.19309.4</MicrosoftWin32RegistryPackageVersion>
     <SystemComponentModelAnnotationsPackageVersion>4.6.0-preview7.19309.4</SystemComponentModelAnnotationsPackageVersion>

src/SignalR/clients/csharp/Client.Core/src/HubConnection.cs

@@ -49,9 +49,8 @@ public partial class HubConnection
         };
 
         private static readonly MethodInfo _sendStreamItemsMethod = typeof(HubConnection).GetMethods(BindingFlags.NonPublic | BindingFlags.Instance).Single(m => m.Name.Equals(nameof(SendStreamItems)));
-#if NETSTANDARD2_1 || NETCOREAPP3_0
         private static readonly MethodInfo _sendIAsyncStreamItemsMethod = typeof(HubConnection).GetMethods(BindingFlags.NonPublic | BindingFlags.Instance).Single(m => m.Name.Equals(nameof(SendIAsyncEnumerableStreamItems)));
-#endif
+
         // Persistent across all connections
         private readonly ILoggerFactory _loggerFactory;
         private readonly ILogger _logger;
@@ -522,7 +521,6 @@ private async Task StopAsyncCore(bool disposing)
             }
         }
 
-#if NETSTANDARD2_1 || NETCOREAPP3_0
         /// <summary>
         /// Invokes a streaming hub method on the server using the specified method name, return type and arguments.
         /// </summary>
@@ -559,7 +557,6 @@ private async IAsyncEnumerable<T> CastIAsyncEnumerable<T>(string methodName, obj
                 cts.Dispose();
             }
         }
-#endif
 
         private async Task<ChannelReader<object>> StreamAsChannelCoreAsyncCore(string methodName, Type returnType, object[] args, CancellationToken cancellationToken)
         {
@@ -674,15 +671,13 @@ private void LaunchStreams(ConnectionState connectionState, Dictionary<string, o
                 // For each stream that needs to be sent, run a "send items" task in the background.
                 // This reads from the channel, attaches streamId, and sends to server.
                 // A single background thread here quickly gets messy.
-#if NETSTANDARD2_1 || NETCOREAPP3_0
                 if (ReflectionHelper.IsIAsyncEnumerable(reader.GetType()))
                 {
                     _ = _sendIAsyncStreamItemsMethod
                         .MakeGenericMethod(reader.GetType().GetInterface("IAsyncEnumerable`1").GetGenericArguments())
                         .Invoke(this, new object[] { connectionState, kvp.Key.ToString(), reader, cancellationToken });
                     continue;
                 }
-#endif
                 _ = _sendStreamItemsMethod
                     .MakeGenericMethod(reader.GetType().GetGenericArguments())
                     .Invoke(this, new object[] { connectionState, kvp.Key.ToString(), reader, cancellationToken });
@@ -707,7 +702,6 @@ async Task ReadChannelStream(CancellationTokenSource tokenSource)
             return CommonStreaming(connectionState, streamId, token, ReadChannelStream);
         }
 
-#if NETSTANDARD2_1 || NETCOREAPP3_0
         // this is called via reflection using the `_sendIAsyncStreamItemsMethod` field
         private Task SendIAsyncEnumerableStreamItems<T>(ConnectionState connectionState, string streamId, IAsyncEnumerable<T> stream, CancellationToken token)
         {
@@ -724,7 +718,6 @@ async Task ReadAsyncEnumerableStream(CancellationTokenSource tokenSource)
 
             return CommonStreaming(connectionState, streamId, token, ReadAsyncEnumerableStream);
         }
-#endif
 
         private async Task CommonStreaming(ConnectionState connectionState, string streamId, CancellationToken token, Func<CancellationTokenSource, Task> createAndConsumeStream)
         {

src/SignalR/clients/csharp/Client.Core/src/HubConnectionExtensions.StreamAsync.cs

@@ -14,9 +14,6 @@ namespace Microsoft.AspNetCore.SignalR.Client
     /// </summary>
     public static partial class HubConnectionExtensions
     {
-
-#if NETSTANDARD2_1 || NETCOREAPP3_0
-
         /// <summary>
         /// Invokes a streaming hub method on the server using the specified method name and return type.
         /// </summary>
@@ -236,7 +233,5 @@ public static IAsyncEnumerable<TResult> StreamAsync<TResult>(this HubConnection
         {
             return hubConnection.StreamAsyncCore<TResult>(methodName, new[] { arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9, arg10 }, cancellationToken);
         }
-#endif
-
     }
 }

src/SignalR/clients/csharp/Client.Core/src/Microsoft.AspNetCore.SignalR.Client.Core.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <Description>Client for ASP.NET Core SignalR</Description>
@@ -28,6 +28,10 @@
     <Reference Include="System.Threading.Channels" />
   </ItemGroup>
 
+  <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
+    <Reference Include="Microsoft.Bcl.AsyncInterfaces" />
+  </ItemGroup>
+
   <ItemGroup Condition="'$(AspNetCoreMajorMinorVersion)' == '3.0'">
     <!-- This dependency was replaced by Protocols.NewtonsoftJson between 3.0 and 2.2. This suppression can be removed after 3.0 is complete. -->
     <SuppressBaselineReference Include="Microsoft.AspNetCore.SignalR.Protocols.Json" />

src/SignalR/common/Shared/AsyncEnumerableAdapters.cs

@@ -13,7 +13,6 @@ namespace Microsoft.AspNetCore.SignalR.Internal
     // True-internal because this is a weird and tricky class to use :)
     internal static class AsyncEnumerableAdapters
     {
-#if NETSTANDARD2_1 || NETCOREAPP3_0
         public static IAsyncEnumerable<object> MakeCancelableAsyncEnumerable<T>(IAsyncEnumerable<T> asyncEnumerable, CancellationToken cancellationToken = default)
         {
             return new CancelableAsyncEnumerable<T>(asyncEnumerable, cancellationToken);
@@ -142,6 +141,5 @@ public ValueTask DisposeAsync()
                 }
             }
         }
-#endif
     }
 }

src/SignalR/common/Shared/ReflectionHelper.cs

@@ -16,12 +16,10 @@ public static bool IsStreamingType(Type type, bool mustBeDirectType = false)
         {
             // TODO #2594 - add Streams here, to make sending files easy
 
-#if NETSTANDARD2_1 || NETCOREAPP3_0
             if (IsIAsyncEnumerable(type))
             {
                 return true;
             }
-#endif
             do
             {
                 if (type.IsGenericType && type.GetGenericTypeDefinition() == typeof(ChannelReader<>))
@@ -35,7 +33,6 @@ public static bool IsStreamingType(Type type, bool mustBeDirectType = false)
             return false;
         }
 
-#if NETSTANDARD2_1 || NETCOREAPP3_0
         public static bool IsIAsyncEnumerable(Type type)
         {
             if (type.IsGenericType)
@@ -55,6 +52,5 @@ public static bool IsIAsyncEnumerable(Type type)
                 }
             });
         }
-#endif
     }
 }