Initial checkin of gRPC to third_party/

third_party/grpc/src/csharp/Grpc.Core/ServerCallContext.cs

+#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.Runtime.CompilerServices;
+using System.Threading;
+using System.Threading.Tasks;
+
+using Grpc.Core.Internal;
+
+namespace Grpc.Core
+{
+    /// <summary>
+    /// Context for a server-side call.
+    /// </summary>
+    public class ServerCallContext
+    {
+        private readonly CallSafeHandle callHandle;
+        private readonly string method;
+        private readonly string host;
+        private readonly string peer;
+        private readonly DateTime deadline;
+        private readonly Metadata requestHeaders;
+        private readonly CancellationToken cancellationToken;
+        private readonly Metadata responseTrailers = new Metadata();
+
+        private Status status = Status.DefaultSuccess;
+        private Func<Metadata, Task> writeHeadersFunc;
+        private IHasWriteOptions writeOptionsHolder;
+
+        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;
+            this.deadline = deadline;
+            this.requestHeaders = requestHeaders;
+            this.cancellationToken = cancellationToken;
+            this.writeHeadersFunc = writeHeadersFunc;
+            this.writeOptionsHolder = writeOptionsHolder;
+        }
+
+        /// <summary>
+        /// Asynchronously sends response headers for the current call to the client. This method may only be invoked once for each call and needs to be invoked
+        /// before any response messages are written. Writing the first response message implicitly sends empty response headers if <c>WriteResponseHeadersAsync</c> haven't
+        /// been called yet.
+        /// </summary>
+        /// <param name="responseHeaders">The response headers to send.</param>
+        /// <returns>The task that finished once response headers have been written.</returns>
+        public Task WriteResponseHeadersAsync(Metadata responseHeaders)
+        {
+            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
+        {
+            get
+            {
+                return this.method;
+            }
+        }
+
+        /// <summary>Name of host called in this RPC.</summary>
+        public string Host
+        {
+            get
+            {
+                return this.host;
+            }
+        }
+
+        /// <summary>Address of the remote endpoint in URI format.</summary>
+        public string Peer
+        {
+            get
+            {
+                return this.peer;
+            }
+        }
+
+        /// <summary>Deadline for this RPC.</summary>
+        public DateTime Deadline
+        {
+            get
+            {
+                return this.deadline;
+            }
+        }
+
+        /// <summary>Initial metadata sent by client.</summary>
+        public Metadata RequestHeaders
+        {
+            get
+            {
+                return this.requestHeaders;
+            }
+        }
+
+        /// <summary>Cancellation token signals when call is cancelled.</summary>
+        public CancellationToken CancellationToken
+        {
+            get
+            {
+                return this.cancellationToken;
+            }
+        }
+
+        /// <summary>Trailers to send back to client after RPC finishes.</summary>
+        public Metadata ResponseTrailers
+        {
+            get
+            {
+                return this.responseTrailers;
+            }
+        }
+
+        /// <summary> Status to send back to client after RPC finishes.</summary>
+        public Status Status
+        {
+            get
+            {
+                return this.status;
+            }
+
+            set
+            {
+                status = value;
+            }
+        }
+
+        /// <summary>
+        /// Allows setting write options for the following write.
+        /// For streaming response calls, this property is also exposed as on IServerStreamWriter for convenience.
+        /// Both properties are backed by the same underlying value.
+        /// </summary>
+        public WriteOptions WriteOptions
+        {
+            get
+            {
+                return writeOptionsHolder.WriteOptions;
+            }
+
+            set
+            {
+                writeOptionsHolder.WriteOptions = value;
+            }
+        }
+    }
+
+    /// <summary>
+    /// Allows sharing write options between ServerCallContext and other objects.
+    /// </summary>
+    public interface IHasWriteOptions
+    {
+        /// <summary>
+        /// Gets or sets the write options.
+        /// </summary>
+        WriteOptions WriteOptions { get; set; }
+    }
+}