| #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.Diagnostics; |
| using System.Runtime.CompilerServices; |
| using System.Runtime.InteropServices; |
| using System.Threading; |
| using System.Threading.Tasks; |
| using Grpc.Core.Internal; |
| using Grpc.Core.Utils; |
| |
| namespace Grpc.Core.Internal |
| { |
| /// <summary> |
| /// Manages server side native call lifecycle. |
| /// </summary> |
| internal class AsyncCallServer<TRequest, TResponse> : AsyncCallBase<TResponse, TRequest> |
| { |
| readonly TaskCompletionSource<object> finishedServersideTcs = new TaskCompletionSource<object>(); |
| readonly CancellationTokenSource cancellationTokenSource = new CancellationTokenSource(); |
| readonly Server server; |
| |
| public AsyncCallServer(Func<TResponse, byte[]> serializer, Func<byte[], TRequest> deserializer, GrpcEnvironment environment, Server server) : base(serializer, deserializer, environment) |
| { |
| this.server = Preconditions.CheckNotNull(server); |
| } |
| |
| public void Initialize(CallSafeHandle call) |
| { |
| call.Initialize(environment.CompletionRegistry, environment.CompletionQueue); |
| |
| server.AddCallReference(this); |
| InitializeInternal(call); |
| } |
| |
| /// <summary> |
| /// Starts a server side call. |
| /// </summary> |
| public Task ServerSideCallAsync() |
| { |
| lock (myLock) |
| { |
| Preconditions.CheckNotNull(call); |
| |
| started = true; |
| |
| call.StartServerSide(HandleFinishedServerside); |
| return finishedServersideTcs.Task; |
| } |
| } |
| |
| /// <summary> |
| /// Sends a streaming response. Only one pending send action is allowed at any given time. |
| /// completionDelegate is called when the operation finishes. |
| /// </summary> |
| public void StartSendMessage(TResponse msg, WriteFlags writeFlags, AsyncCompletionDelegate<object> completionDelegate) |
| { |
| StartSendMessageInternal(msg, writeFlags, completionDelegate); |
| } |
| |
| /// <summary> |
| /// Receives a streaming request. Only one pending read action is allowed at any given time. |
| /// completionDelegate is called when the operation finishes. |
| /// </summary> |
| public void StartReadMessage(AsyncCompletionDelegate<TRequest> completionDelegate) |
| { |
| StartReadMessageInternal(completionDelegate); |
| } |
| |
| /// <summary> |
| /// Initiates sending a initial metadata. |
| /// Even though C-core allows sending metadata in parallel to sending messages, we will treat sending metadata as a send message operation |
| /// to make things simpler. |
| /// completionDelegate is invoked upon completion. |
| /// </summary> |
| public void StartSendInitialMetadata(Metadata headers, AsyncCompletionDelegate<object> completionDelegate) |
| { |
| lock (myLock) |
| { |
| Preconditions.CheckNotNull(headers, "metadata"); |
| Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null"); |
| |
| Preconditions.CheckState(!initialMetadataSent, "Response headers can only be sent once per call."); |
| Preconditions.CheckState(streamingWritesCounter == 0, "Response headers can only be sent before the first write starts."); |
| CheckSendingAllowed(); |
| |
| Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null"); |
| |
| using (var metadataArray = MetadataArraySafeHandle.Create(headers)) |
| { |
| call.StartSendInitialMetadata(HandleSendFinished, metadataArray); |
| } |
| |
| this.initialMetadataSent = true; |
| sendCompletionDelegate = completionDelegate; |
| } |
| } |
| |
| /// <summary> |
| /// Sends call result status, also indicating server is done with streaming responses. |
| /// Only one pending send action is allowed at any given time. |
| /// completionDelegate is called when the operation finishes. |
| /// </summary> |
| public void StartSendStatusFromServer(Status status, Metadata trailers, AsyncCompletionDelegate<object> completionDelegate) |
| { |
| lock (myLock) |
| { |
| Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null"); |
| CheckSendingAllowed(); |
| |
| using (var metadataArray = MetadataArraySafeHandle.Create(trailers)) |
| { |
| call.StartSendStatusFromServer(HandleHalfclosed, status, metadataArray, !initialMetadataSent); |
| } |
| halfcloseRequested = true; |
| readingDone = true; |
| sendCompletionDelegate = completionDelegate; |
| } |
| } |
| |
| /// <summary> |
| /// Gets cancellation token that gets cancelled once close completion |
| /// is received and the cancelled flag is set. |
| /// </summary> |
| public CancellationToken CancellationToken |
| { |
| get |
| { |
| return cancellationTokenSource.Token; |
| } |
| } |
| |
| public string Peer |
| { |
| get |
| { |
| return call.GetPeer(); |
| } |
| } |
| |
| protected override bool IsClient |
| { |
| get { return false; } |
| } |
| |
| protected override void CheckReadingAllowed() |
| { |
| base.CheckReadingAllowed(); |
| Preconditions.CheckArgument(!cancelRequested); |
| } |
| |
| protected override void OnAfterReleaseResources() |
| { |
| server.RemoveCallReference(this); |
| } |
| |
| /// <summary> |
| /// Handles the server side close completion. |
| /// </summary> |
| private void HandleFinishedServerside(bool success, bool cancelled) |
| { |
| lock (myLock) |
| { |
| finished = true; |
| |
| if (cancelled) |
| { |
| // Once we cancel, we don't have to care that much |
| // about reads and writes. |
| |
| // TODO(jtattermusch): is this still necessary? |
| Cancel(); |
| } |
| |
| ReleaseResourcesIfPossible(); |
| } |
| // TODO(jtattermusch): handle error |
| |
| if (cancelled) |
| { |
| cancellationTokenSource.Cancel(); |
| } |
| |
| finishedServersideTcs.SetResult(null); |
| } |
| } |
| } |