src/csharp/Grpc.Core/Internal/ServerResponseStream.cs

#region Copyright notice and license
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//
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// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
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#endregion

using System;
using System.Threading.Tasks;
using Grpc.Core.Internal;

namespace Grpc.Core.Internal
{
    /// <summary>
    /// Writes responses asynchronously to an underlying AsyncCallServer object.
    /// </summary>
    internal class ServerResponseStream<TRequest, TResponse> : IServerStreamWriter<TResponse>
        where TRequest : class
        where TResponse : class
    {
        readonly AsyncCallServer<TRequest, TResponse> call;

        public ServerResponseStream(AsyncCallServer<TRequest, TResponse> call)
        {
            this.call = call;
        }

        public Task WriteAsync(TResponse message)
        {
            var taskSource = new AsyncCompletionTaskSource<object>();
            call.StartSendMessage(message, taskSource.CompletionDelegate);
            return taskSource.Task;
        }

        public Task WriteStatusAsync(Status status)
        {
            var taskSource = new AsyncCompletionTaskSource<object>();
            call.StartSendStatusFromServer(status, taskSource.CompletionDelegate);
            return taskSource.Task;
        }
    }
}