improve channel behavior in shutdown situations
diff --git a/src/csharp/Grpc.Core.Tests/ChannelTest.cs b/src/csharp/Grpc.Core.Tests/ChannelTest.cs
index 6330f50..850d70c 100644
--- a/src/csharp/Grpc.Core.Tests/ChannelTest.cs
+++ b/src/csharp/Grpc.Core.Tests/ChannelTest.cs
@@ -32,6 +32,7 @@
#endregion
using System;
+using System.Threading.Tasks;
using Grpc.Core;
using Grpc.Core.Internal;
using Grpc.Core.Utils;
@@ -89,5 +90,43 @@
channel.ShutdownAsync().Wait();
Assert.ThrowsAsync(typeof(InvalidOperationException), async () => await channel.ShutdownAsync());
}
+
+ [Test]
+ public async Task ShutdownTokenCancelledAfterShutdown()
+ {
+ var channel = new Channel("localhost", ChannelCredentials.Insecure);
+ Assert.IsFalse(channel.ShutdownToken.IsCancellationRequested);
+ var shutdownTask = channel.ShutdownAsync();
+ Assert.IsTrue(channel.ShutdownToken.IsCancellationRequested);
+ await shutdownTask;
+ }
+
+ [Test]
+ public async Task StateIsFatalFailureAfterShutdown()
+ {
+ var channel = new Channel("localhost", ChannelCredentials.Insecure);
+ await channel.ShutdownAsync();
+ Assert.AreEqual(ChannelState.FatalFailure, channel.State);
+ }
+
+ [Test]
+ public async Task ShutdownFinishesWaitForStateChangedAsync()
+ {
+ var channel = new Channel("localhost", ChannelCredentials.Insecure);
+ var stateChangedTask = channel.WaitForStateChangedAsync(ChannelState.Idle);
+ var shutdownTask = channel.ShutdownAsync();
+ await stateChangedTask;
+ await shutdownTask;
+ }
+
+ [Test]
+ public async Task OperationsThrowAfterShutdown()
+ {
+ var channel = new Channel("localhost", ChannelCredentials.Insecure);
+ await channel.ShutdownAsync();
+ Assert.ThrowsAsync(typeof(ObjectDisposedException), async () => await channel.WaitForStateChangedAsync(ChannelState.Idle));
+ Assert.Throws(typeof(ObjectDisposedException), () => { var x = channel.ResolvedTarget; });
+ Assert.ThrowsAsync(typeof(TaskCanceledException), async () => await channel.ConnectAsync());
+ }
}
}
diff --git a/src/csharp/Grpc.Core/Channel.cs b/src/csharp/Grpc.Core/Channel.cs
index 89981b1..93a6e6a 100644
--- a/src/csharp/Grpc.Core/Channel.cs
+++ b/src/csharp/Grpc.Core/Channel.cs
@@ -32,6 +32,7 @@
using System;
using System.Collections.Generic;
using System.Linq;
+using System.Threading;
using System.Threading.Tasks;
using Grpc.Core.Internal;
@@ -51,6 +52,7 @@
readonly object myLock = new object();
readonly AtomicCounter activeCallCounter = new AtomicCounter();
+ readonly CancellationTokenSource shutdownTokenSource = new CancellationTokenSource();
readonly string target;
readonly GrpcEnvironment environment;
@@ -101,12 +103,13 @@
/// <summary>
/// Gets current connectivity state of this channel.
+ /// After channel is has been shutdown, <c>ChannelState.FatalFailure</c> will be returned.
/// </summary>
public ChannelState State
{
get
{
- return handle.CheckConnectivityState(false);
+ return GetConnectivityState(false);
}
}
@@ -155,6 +158,17 @@
}
/// <summary>
+ /// Returns a token that gets cancelled once <c>ShutdownAsync</c> is invoked.
+ /// </summary>
+ public CancellationToken ShutdownToken
+ {
+ get
+ {
+ return this.shutdownTokenSource.Token;
+ }
+ }
+
+ /// <summary>
/// Allows explicitly requesting channel to connect without starting an RPC.
/// Returned task completes once state Ready was seen. If the deadline is reached,
/// or channel enters the FatalFailure state, the task is cancelled.
@@ -164,7 +178,7 @@
/// <param name="deadline">The deadline. <c>null</c> indicates no deadline.</param>
public async Task ConnectAsync(DateTime? deadline = null)
{
- var currentState = handle.CheckConnectivityState(true);
+ var currentState = GetConnectivityState(true);
while (currentState != ChannelState.Ready)
{
if (currentState == ChannelState.FatalFailure)
@@ -172,7 +186,7 @@
throw new OperationCanceledException("Channel has reached FatalFailure state.");
}
await WaitForStateChangedAsync(currentState, deadline).ConfigureAwait(false);
- currentState = handle.CheckConnectivityState(false);
+ currentState = GetConnectivityState(false);
}
}
@@ -188,6 +202,8 @@
shutdownRequested = true;
}
+ shutdownTokenSource.Cancel();
+
var activeCallCount = activeCallCounter.Count;
if (activeCallCount > 0)
{
@@ -231,6 +247,18 @@
activeCallCounter.Decrement();
}
+ private ChannelState GetConnectivityState(bool tryToConnect)
+ {
+ try
+ {
+ return handle.CheckConnectivityState(tryToConnect);
+ }
+ catch (ObjectDisposedException)
+ {
+ return ChannelState.FatalFailure;
+ }
+ }
+
private static void EnsureUserAgentChannelOption(Dictionary<string, ChannelOption> options)
{
var key = ChannelOptions.PrimaryUserAgentString;