context propagation API
diff --git a/src/csharp/Grpc.Core/CallOptions.cs b/src/csharp/Grpc.Core/CallOptions.cs
index a08986d..0d82b5a 100644
--- a/src/csharp/Grpc.Core/CallOptions.cs
+++ b/src/csharp/Grpc.Core/CallOptions.cs
@@ -48,6 +48,7 @@
readonly DateTime deadline;
readonly CancellationToken cancellationToken;
readonly WriteOptions writeOptions;
+ readonly ContextPropagationToken propagationToken;
/// <summary>
/// Creates a new instance of <c>CallOptions</c>.
@@ -56,14 +57,16 @@
/// <param name="deadline">Deadline for the call to finish. null means no deadline.</param>
/// <param name="cancellationToken">Can be used to request cancellation of the call.</param>
/// <param name="writeOptions">Write options that will be used for this call.</param>
- public CallOptions(Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken), WriteOptions writeOptions = null)
+ /// <param name="propagationToken">Context propagation token obtained from <see cref="ServerCallContext"/>.</param>
+ public CallOptions(Metadata headers = null, DateTime? deadline = null, CancellationToken? cancellationToken = null,
+ WriteOptions writeOptions = null, ContextPropagationToken propagationToken = null)
{
// TODO(jtattermusch): consider only creating metadata object once it's really needed.
- this.headers = headers != null ? headers : new Metadata();
- // TODO(jtattermusch): allow null value of deadline?
- this.deadline = deadline.HasValue ? deadline.Value : DateTime.MaxValue;
- this.cancellationToken = cancellationToken;
+ this.headers = headers ?? new Metadata();
+ this.deadline = deadline ?? (propagationToken != null ? propagationToken.Deadline : DateTime.MaxValue);
+ this.cancellationToken = cancellationToken ?? (propagationToken != null ? propagationToken.CancellationToken : CancellationToken.None);
this.writeOptions = writeOptions;
+ this.propagationToken = propagationToken;
}
/// <summary>
@@ -100,5 +103,16 @@
return this.writeOptions;
}
}
+
+ /// <summary>
+ /// Token for propagating parent call context.
+ /// </summary>
+ public ContextPropagationToken PropagationToken
+ {
+ get
+ {
+ return this.propagationToken;
+ }
+ }
}
}
diff --git a/src/csharp/Grpc.Core/ContextPropagationToken.cs b/src/csharp/Grpc.Core/ContextPropagationToken.cs
new file mode 100644
index 0000000..e765947
--- /dev/null
+++ b/src/csharp/Grpc.Core/ContextPropagationToken.cs
@@ -0,0 +1,139 @@
+#region Copyright notice and license
+
+// Copyright 2015, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#endregion
+
+using System;
+using System.Threading;
+
+using Grpc.Core.Internal;
+using Grpc.Core.Utils;
+
+namespace Grpc.Core
+{
+ /// <summary>
+ /// Token for propagating context of server side handlers to child calls.
+ /// In situations when a backend is making calls to another backend,
+ /// it makes sense to propagate properties like deadline and cancellation
+ /// token of the server call to the child call.
+ /// C core provides some other contexts (like tracing context) that
+ /// are not accessible to C# layer, but this token still allows propagating them.
+ /// </summary>
+ public class ContextPropagationToken
+ {
+ /// <summary>
+ /// Default propagation mask used by C core.
+ /// </summary>
+ const ContextPropagationFlags DefaultCoreMask = (ContextPropagationFlags) 0xffff;
+
+ /// <summary>
+ /// Default propagation mask used by C# - we want to propagate deadline
+ /// and cancellation token by our own means.
+ /// </summary>
+ internal const ContextPropagationFlags DefaultMask = DefaultCoreMask
+ & ~ContextPropagationFlags.Deadline & ~ContextPropagationFlags.Cancellation;
+
+ readonly CallSafeHandle parentCall;
+ readonly DateTime deadline;
+ readonly CancellationToken cancellationToken;
+ readonly ContextPropagationOptions options;
+
+ internal ContextPropagationToken(CallSafeHandle parentCall, DateTime deadline, CancellationToken cancellationToken, ContextPropagationOptions options)
+ {
+ this.parentCall = Preconditions.CheckNotNull(parentCall);
+ this.deadline = deadline;
+ this.cancellationToken = cancellationToken;
+ this.options = options ?? ContextPropagationOptions.Default;
+ }
+
+ internal CallSafeHandle ParentCall
+ {
+ get
+ {
+ return this.parentCall;
+ }
+ }
+
+ internal DateTime Deadline
+ {
+ get
+ {
+ return this.deadline;
+ }
+ }
+
+ internal CancellationToken CancellationToken
+ {
+ get
+ {
+ return this.cancellationToken;
+ }
+ }
+
+ internal ContextPropagationOptions Options
+ {
+ get
+ {
+ return this.options;
+ }
+ }
+
+ internal bool IsPropagateDeadline
+ {
+ get { return false; }
+ }
+
+ internal bool IsPropagateCancellation
+ {
+ get { return false; }
+ }
+ }
+
+ /// <summary>
+ /// Options for <see cref="ContextPropagationToken"/>.
+ /// </summary>
+ public class ContextPropagationOptions
+ {
+ public static readonly ContextPropagationOptions Default = new ContextPropagationOptions();
+ }
+
+ /// <summary>
+ /// Context propagation flags from grpc/grpc.h.
+ /// </summary>
+ [Flags]
+ internal enum ContextPropagationFlags
+ {
+ Deadline = 1,
+ CensusStatsContext = 2,
+ CensusTracingContext = 4,
+ Cancellation = 8
+ }
+}
diff --git a/src/csharp/Grpc.Core/Grpc.Core.csproj b/src/csharp/Grpc.Core/Grpc.Core.csproj
index 0616ed9..e535c47 100644
--- a/src/csharp/Grpc.Core/Grpc.Core.csproj
+++ b/src/csharp/Grpc.Core/Grpc.Core.csproj
@@ -117,6 +117,7 @@
<Compile Include="CallOptions.cs" />
<Compile Include="CompressionLevel.cs" />
<Compile Include="WriteOptions.cs" />
+ <Compile Include="ContextPropagationToken.cs" />
</ItemGroup>
<ItemGroup>
<None Include="Grpc.Core.nuspec" />
diff --git a/src/csharp/Grpc.Core/Internal/AsyncCall.cs b/src/csharp/Grpc.Core/Internal/AsyncCall.cs
index dee31c6..0db9d2a 100644
--- a/src/csharp/Grpc.Core/Internal/AsyncCall.cs
+++ b/src/csharp/Grpc.Core/Internal/AsyncCall.cs
@@ -324,7 +324,11 @@
private void Initialize(CompletionQueueSafeHandle cq)
{
- var call = details.Channel.Handle.CreateCall(details.Channel.Environment.CompletionRegistry, cq,
+ var propagationToken = details.Options.PropagationToken;
+ var parentCall = propagationToken != null ? propagationToken.ParentCall : CallSafeHandle.NullInstance;
+
+ var call = details.Channel.Handle.CreateCall(details.Channel.Environment.CompletionRegistry,
+ parentCall, ContextPropagationToken.DefaultMask, cq,
details.Method, details.Host, Timespec.FromDateTime(details.Options.Deadline));
details.Channel.Environment.DebugStats.ActiveClientCalls.Increment();
InitializeInternal(call);
diff --git a/src/csharp/Grpc.Core/Internal/CallSafeHandle.cs b/src/csharp/Grpc.Core/Internal/CallSafeHandle.cs
index 1b9d0ab..3cb01e2 100644
--- a/src/csharp/Grpc.Core/Internal/CallSafeHandle.cs
+++ b/src/csharp/Grpc.Core/Internal/CallSafeHandle.cs
@@ -42,6 +42,8 @@
/// </summary>
internal class CallSafeHandle : SafeHandleZeroIsInvalid
{
+ public static readonly CallSafeHandle NullInstance = new CallSafeHandle();
+
const uint GRPC_WRITE_BUFFER_HINT = 1;
CompletionRegistry completionRegistry;
diff --git a/src/csharp/Grpc.Core/Internal/ChannelSafeHandle.cs b/src/csharp/Grpc.Core/Internal/ChannelSafeHandle.cs
index 7324ebd..7f03bf4 100644
--- a/src/csharp/Grpc.Core/Internal/ChannelSafeHandle.cs
+++ b/src/csharp/Grpc.Core/Internal/ChannelSafeHandle.cs
@@ -47,7 +47,7 @@
static extern ChannelSafeHandle grpcsharp_secure_channel_create(CredentialsSafeHandle credentials, string target, ChannelArgsSafeHandle channelArgs);
[DllImport("grpc_csharp_ext.dll")]
- static extern CallSafeHandle grpcsharp_channel_create_call(ChannelSafeHandle channel, CompletionQueueSafeHandle cq, string method, string host, Timespec deadline);
+ static extern CallSafeHandle grpcsharp_channel_create_call(ChannelSafeHandle channel, CallSafeHandle parentCall, ContextPropagationFlags propagationMask, CompletionQueueSafeHandle cq, string method, string host, Timespec deadline);
[DllImport("grpc_csharp_ext.dll")]
static extern ChannelState grpcsharp_channel_check_connectivity_state(ChannelSafeHandle channel, int tryToConnect);
@@ -76,9 +76,9 @@
return grpcsharp_secure_channel_create(credentials, target, channelArgs);
}
- public CallSafeHandle CreateCall(CompletionRegistry registry, CompletionQueueSafeHandle cq, string method, string host, Timespec deadline)
+ public CallSafeHandle CreateCall(CompletionRegistry registry, CallSafeHandle parentCall, ContextPropagationFlags propagationMask, CompletionQueueSafeHandle cq, string method, string host, Timespec deadline)
{
- var result = grpcsharp_channel_create_call(this, cq, method, host, deadline);
+ var result = grpcsharp_channel_create_call(this, parentCall, propagationMask, cq, method, host, deadline);
result.SetCompletionRegistry(registry);
return result;
}
diff --git a/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs b/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs
index 74af19d..688f9f6 100644
--- a/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs
+++ b/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs
@@ -310,8 +310,7 @@
{
DateTime realtimeDeadline = newRpc.Deadline.ToClockType(GPRClockType.Realtime).ToDateTime();
- return new ServerCallContext(
- newRpc.Method, newRpc.Host, peer, realtimeDeadline,
+ return new ServerCallContext(newRpc.Call, newRpc.Method, newRpc.Host, peer, realtimeDeadline,
newRpc.RequestMetadata, cancellationToken, serverResponseStream.WriteResponseHeadersAsync, serverResponseStream);
}
}
diff --git a/src/csharp/Grpc.Core/ServerCallContext.cs b/src/csharp/Grpc.Core/ServerCallContext.cs
index 7849df9..75d81c6 100644
--- a/src/csharp/Grpc.Core/ServerCallContext.cs
+++ b/src/csharp/Grpc.Core/ServerCallContext.cs
@@ -45,6 +45,7 @@
/// </summary>
public class ServerCallContext
{
+ private readonly CallSafeHandle callHandle;
private readonly string method;
private readonly string host;
private readonly string peer;
@@ -57,9 +58,10 @@
private Func<Metadata, Task> writeHeadersFunc;
private IHasWriteOptions writeOptionsHolder;
- public ServerCallContext(string method, string host, string peer, DateTime deadline, Metadata requestHeaders, CancellationToken cancellationToken,
+ internal ServerCallContext(CallSafeHandle callHandle, string method, string host, string peer, DateTime deadline, Metadata requestHeaders, CancellationToken cancellationToken,
Func<Metadata, Task> writeHeadersFunc, IHasWriteOptions writeOptionsHolder)
{
+ this.callHandle = callHandle;
this.method = method;
this.host = host;
this.peer = peer;
@@ -74,6 +76,14 @@
{
return writeHeadersFunc(responseHeaders);
}
+
+ /// <summary>
+ /// Creates a propagation token to be used to propagate call context to a child call.
+ /// </summary>
+ public ContextPropagationToken CreatePropagationToken(ContextPropagationOptions options = null)
+ {
+ return new ContextPropagationToken(callHandle, deadline, cancellationToken, options);
+ }
/// <summary>Name of method called in this RPC.</summary>
public string Method
diff --git a/src/csharp/ext/grpc_csharp_ext.c b/src/csharp/ext/grpc_csharp_ext.c
index 5d17360..133b2d8 100644
--- a/src/csharp/ext/grpc_csharp_ext.c
+++ b/src/csharp/ext/grpc_csharp_ext.c
@@ -376,10 +376,12 @@
}
GPR_EXPORT grpc_call *GPR_CALLTYPE
-grpcsharp_channel_create_call(grpc_channel *channel, grpc_completion_queue *cq,
+grpcsharp_channel_create_call(grpc_channel *channel, grpc_call *parent_call,
+ gpr_uint32 propagation_mask,
+ grpc_completion_queue *cq,
const char *method, const char *host,
gpr_timespec deadline) {
- return grpc_channel_create_call(channel, NULL, GRPC_PROPAGATE_DEFAULTS, cq,
+ return grpc_channel_create_call(channel, parent_call, propagation_mask, cq,
method, host, deadline);
}