Initial checkin of gRPC to third_party/

third_party/grpc/src/csharp/Grpc.IntegrationTesting/InteropClient.cs

Index: third_party/grpc/src/csharp/Grpc.IntegrationTesting/InteropClient.cs
diff --git a/third_party/grpc/src/csharp/Grpc.IntegrationTesting/InteropClient.cs b/third_party/grpc/src/csharp/Grpc.IntegrationTesting/InteropClient.cs
new file mode 100644
index 0000000000000000000000000000000000000000..b0e33e49f77eefabf6a80ada6e0b22e2ab6f2fae
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+++ b/third_party/grpc/src/csharp/Grpc.IntegrationTesting/InteropClient.cs
@@ -0,0 +1,619 @@
+#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.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text.RegularExpressions;
+using System.Threading;
+using System.Threading.Tasks;
+
+using CommandLine;
+using CommandLine.Text;
+using Google.Apis.Auth.OAuth2;
+using Google.Protobuf;
+using Grpc.Auth;
+using Grpc.Core;
+using Grpc.Core.Utils;
+using Grpc.Testing;
+using Newtonsoft.Json.Linq;
+using NUnit.Framework;
+
+namespace Grpc.IntegrationTesting
+{
+    public class InteropClient
+    {
+        private class ClientOptions
+        {
+            [Option("server_host", DefaultValue = "127.0.0.1")]
+            public string ServerHost { get; set; }
+
+            [Option("server_host_override", DefaultValue = TestCredentials.DefaultHostOverride)]
+            public string ServerHostOverride { get; set; }
+
+            [Option("server_port", Required = true)]
+            public int ServerPort { get; set; }
+
+            [Option("test_case", DefaultValue = "large_unary")]
+            public string TestCase { get; set; }
+
+            // Deliberately using nullable bool type to allow --use_tls=true syntax (as opposed to --use_tls)
+            [Option("use_tls", DefaultValue = false)]
+            public bool? UseTls { get; set; }
+
+            // Deliberately using nullable bool type to allow --use_test_ca=true syntax (as opposed to --use_test_ca)
+            [Option("use_test_ca", DefaultValue = false)]
+            public bool? UseTestCa { get; set; }
+
+            [Option("default_service_account", Required = false)]
+            public string DefaultServiceAccount { get; set; }
+
+            [Option("oauth_scope", Required = false)]
+            public string OAuthScope { get; set; }
+
+            [Option("service_account_key_file", Required = false)]
+            public string ServiceAccountKeyFile { get; set; }
+
+            [HelpOption]
+            public string GetUsage()
+            {
+                var help = new HelpText
+                {
+                    Heading = "gRPC C# interop testing client",
+                    AddDashesToOption = true
+                };
+                help.AddPreOptionsLine("Usage:");
+                help.AddOptions(this);
+                return help;
+            }
+        }
+
+        ClientOptions options;
+
+        private InteropClient(ClientOptions options)
+        {
+            this.options = options;
+        }
+
+        public static void Run(string[] args)
+        {
+            var options = new ClientOptions();
+            if (!Parser.Default.ParseArguments(args, options))
+            {
+                Environment.Exit(1);
+            }
+
+            var interopClient = new InteropClient(options);
+            interopClient.Run().Wait();
+        }
+
+        private async Task Run()
+        {
+            var credentials = await CreateCredentialsAsync();
+            
+            List<ChannelOption> channelOptions = null;
+            if (!string.IsNullOrEmpty(options.ServerHostOverride))
+            {
+                channelOptions = new List<ChannelOption>
+                {
+                    new ChannelOption(ChannelOptions.SslTargetNameOverride, options.ServerHostOverride)
+                };
+            }
+            var channel = new Channel(options.ServerHost, options.ServerPort, credentials, channelOptions);
+            await RunTestCaseAsync(channel, options);
+            await channel.ShutdownAsync();
+        }
+
+        private async Task<ChannelCredentials> CreateCredentialsAsync()
+        {
+            var credentials = ChannelCredentials.Insecure;
+            if (options.UseTls.Value)
+            {
+                credentials = options.UseTestCa.Value ? TestCredentials.CreateSslCredentials() : new SslCredentials();
+            }
+
+            if (options.TestCase == "jwt_token_creds")
+            {
+                var googleCredential = await GoogleCredential.GetApplicationDefaultAsync();
+                Assert.IsTrue(googleCredential.IsCreateScopedRequired);
+                credentials = ChannelCredentials.Create(credentials, googleCredential.ToCallCredentials());
+            }
+
+            if (options.TestCase == "compute_engine_creds")
+            {
+                var googleCredential = await GoogleCredential.GetApplicationDefaultAsync();
+                Assert.IsFalse(googleCredential.IsCreateScopedRequired);
+                credentials = ChannelCredentials.Create(credentials, googleCredential.ToCallCredentials());
+            }
+            return credentials;
+        }
+
+        private async Task RunTestCaseAsync(Channel channel, ClientOptions options)
+        {
+            var client = new TestService.TestServiceClient(channel);
+            switch (options.TestCase)
+            {
+                case "empty_unary":
+                    RunEmptyUnary(client);
+                    break;
+                case "large_unary":
+                    RunLargeUnary(client);
+                    break;
+                case "client_streaming":
+                    await RunClientStreamingAsync(client);
+                    break;
+                case "server_streaming":
+                    await RunServerStreamingAsync(client);
+                    break;
+                case "ping_pong":
+                    await RunPingPongAsync(client);
+                    break;
+                case "empty_stream":
+                    await RunEmptyStreamAsync(client);
+                    break;
+                case "compute_engine_creds":
+                    RunComputeEngineCreds(client, options.DefaultServiceAccount, options.OAuthScope);
+                    break;
+                case "jwt_token_creds":
+                    RunJwtTokenCreds(client);
+                    break;
+                case "oauth2_auth_token":
+                    await RunOAuth2AuthTokenAsync(client, options.OAuthScope);
+                    break;
+                case "per_rpc_creds":
+                    await RunPerRpcCredsAsync(client, options.OAuthScope);
+                    break;
+                case "cancel_after_begin":
+                    await RunCancelAfterBeginAsync(client);
+                    break;
+                case "cancel_after_first_response":
+                    await RunCancelAfterFirstResponseAsync(client);
+                    break;
+                case "timeout_on_sleeping_server":
+                    await RunTimeoutOnSleepingServerAsync(client);
+                    break;
+                case "custom_metadata":
+                    await RunCustomMetadataAsync(client);
+                    break;
+                case "status_code_and_message":
+                    await RunStatusCodeAndMessageAsync(client);
+                    break;
+                case "unimplemented_method":
+                    RunUnimplementedMethod(new UnimplementedService.UnimplementedServiceClient(channel));
+                    break;
+                default:
+                    throw new ArgumentException("Unknown test case " + options.TestCase);
+            }
+        }
+
+        public static void RunEmptyUnary(TestService.ITestServiceClient client)
+        {
+            Console.WriteLine("running empty_unary");
+            var response = client.EmptyCall(new Empty());
+            Assert.IsNotNull(response);
+            Console.WriteLine("Passed!");
+        }
+
+        public static void RunLargeUnary(TestService.ITestServiceClient client)
+        {
+            Console.WriteLine("running large_unary");
+            var request = new SimpleRequest
+            {
+                ResponseType = PayloadType.COMPRESSABLE,
+                ResponseSize = 314159,
+                Payload = CreateZerosPayload(271828)
+            };
+            var response = client.UnaryCall(request);
+
+            Assert.AreEqual(PayloadType.COMPRESSABLE, response.Payload.Type);
+            Assert.AreEqual(314159, response.Payload.Body.Length);
+            Console.WriteLine("Passed!");
+        }
+
+        public static async Task RunClientStreamingAsync(TestService.ITestServiceClient client)
+        {
+            Console.WriteLine("running client_streaming");
+
+            var bodySizes = new List<int> { 27182, 8, 1828, 45904 }.ConvertAll((size) => new StreamingInputCallRequest { Payload = CreateZerosPayload(size) });
+
+            using (var call = client.StreamingInputCall())
+            {
+                await call.RequestStream.WriteAllAsync(bodySizes);
+
+                var response = await call.ResponseAsync;
+                Assert.AreEqual(74922, response.AggregatedPayloadSize);
+            }
+            Console.WriteLine("Passed!");
+        }
+
+        public static async Task RunServerStreamingAsync(TestService.ITestServiceClient client)
+        {
+            Console.WriteLine("running server_streaming");
+
+            var bodySizes = new List<int> { 31415, 9, 2653, 58979 };
+
+            var request = new StreamingOutputCallRequest
+            {
+                ResponseType = PayloadType.COMPRESSABLE,
+                ResponseParameters = { bodySizes.ConvertAll((size) => new ResponseParameters { Size = size }) }
+            };
+
+            using (var call = client.StreamingOutputCall(request))
+            {
+                var responseList = await call.ResponseStream.ToListAsync();
+                foreach (var res in responseList)
+                {
+                    Assert.AreEqual(PayloadType.COMPRESSABLE, res.Payload.Type);
+                }
+                CollectionAssert.AreEqual(bodySizes, responseList.ConvertAll((item) => item.Payload.Body.Length));
+            }
+            Console.WriteLine("Passed!");
+        }
+
+        public static async Task RunPingPongAsync(TestService.ITestServiceClient client)
+        {
+            Console.WriteLine("running ping_pong");
+
+            using (var call = client.FullDuplexCall())
+            {
+                await call.RequestStream.WriteAsync(new StreamingOutputCallRequest
+                {
+                    ResponseType = PayloadType.COMPRESSABLE,
+                    ResponseParameters = { new ResponseParameters { Size = 31415 } },
+                    Payload = CreateZerosPayload(27182)
+                });
+
+                Assert.IsTrue(await call.ResponseStream.MoveNext());
+                Assert.AreEqual(PayloadType.COMPRESSABLE, call.ResponseStream.Current.Payload.Type);
+                Assert.AreEqual(31415, call.ResponseStream.Current.Payload.Body.Length);
+
+                await call.RequestStream.WriteAsync(new StreamingOutputCallRequest
+                {
+                    ResponseType = PayloadType.COMPRESSABLE,
+                    ResponseParameters = { new ResponseParameters { Size = 9 } },
+                    Payload = CreateZerosPayload(8)
+                });
+
+                Assert.IsTrue(await call.ResponseStream.MoveNext());
+                Assert.AreEqual(PayloadType.COMPRESSABLE, call.ResponseStream.Current.Payload.Type);
+                Assert.AreEqual(9, call.ResponseStream.Current.Payload.Body.Length);
+
+                await call.RequestStream.WriteAsync(new StreamingOutputCallRequest
+                {
+                    ResponseType = PayloadType.COMPRESSABLE,
+                    ResponseParameters = { new ResponseParameters { Size = 2653 } },
+                    Payload = CreateZerosPayload(1828)
+                });
+
+                Assert.IsTrue(await call.ResponseStream.MoveNext());
+                Assert.AreEqual(PayloadType.COMPRESSABLE, call.ResponseStream.Current.Payload.Type);
+                Assert.AreEqual(2653, call.ResponseStream.Current.Payload.Body.Length);
+
+                await call.RequestStream.WriteAsync(new StreamingOutputCallRequest
+                {
+                    ResponseType = PayloadType.COMPRESSABLE,
+                    ResponseParameters = { new ResponseParameters { Size = 58979 } },
+                    Payload = CreateZerosPayload(45904)
+                });
+
+                Assert.IsTrue(await call.ResponseStream.MoveNext());
+                Assert.AreEqual(PayloadType.COMPRESSABLE, call.ResponseStream.Current.Payload.Type);
+                Assert.AreEqual(58979, call.ResponseStream.Current.Payload.Body.Length);
+
+                await call.RequestStream.CompleteAsync();
+
+                Assert.IsFalse(await call.ResponseStream.MoveNext());
+            }
+            Console.WriteLine("Passed!");
+        }
+
+        public static async Task RunEmptyStreamAsync(TestService.ITestServiceClient client)
+        {
+            Console.WriteLine("running empty_stream");
+            using (var call = client.FullDuplexCall())
+            {
+                await call.RequestStream.CompleteAsync();
+
+                var responseList = await call.ResponseStream.ToListAsync();
+                Assert.AreEqual(0, responseList.Count);
+            }
+            Console.WriteLine("Passed!");
+        }
+
+        public static void RunComputeEngineCreds(TestService.TestServiceClient client, string defaultServiceAccount, string oauthScope)
+        {
+            Console.WriteLine("running compute_engine_creds");
+
+            var request = new SimpleRequest
+            {
+                ResponseType = PayloadType.COMPRESSABLE,
+                ResponseSize = 314159,
+                Payload = CreateZerosPayload(271828),
+                FillUsername = true,
+                FillOauthScope = true
+            };
+
+            // not setting credentials here because they were set on channel already
+            var response = client.UnaryCall(request);
+
+            Assert.AreEqual(PayloadType.COMPRESSABLE, response.Payload.Type);
+            Assert.AreEqual(314159, response.Payload.Body.Length);
+            Assert.False(string.IsNullOrEmpty(response.OauthScope));
+            Assert.True(oauthScope.Contains(response.OauthScope));
+            Assert.AreEqual(defaultServiceAccount, response.Username);
+            Console.WriteLine("Passed!");
+        }
+
+        public static void RunJwtTokenCreds(TestService.TestServiceClient client)
+        {
+            Console.WriteLine("running jwt_token_creds");
+           
+            var request = new SimpleRequest
+            {
+                ResponseType = PayloadType.COMPRESSABLE,
+                ResponseSize = 314159,
+                Payload = CreateZerosPayload(271828),
+                FillUsername = true,
+            };
+
+            // not setting credentials here because they were set on channel already
+            var response = client.UnaryCall(request);
+
+            Assert.AreEqual(PayloadType.COMPRESSABLE, response.Payload.Type);
+            Assert.AreEqual(314159, response.Payload.Body.Length);
+            Assert.AreEqual(GetEmailFromServiceAccountFile(), response.Username);
+            Console.WriteLine("Passed!");
+        }
+
+        public static async Task RunOAuth2AuthTokenAsync(TestService.TestServiceClient client, string oauthScope)
+        {
+            Console.WriteLine("running oauth2_auth_token");
+            ITokenAccess credential = (await GoogleCredential.GetApplicationDefaultAsync()).CreateScoped(new[] { oauthScope });
+            string oauth2Token = await credential.GetAccessTokenForRequestAsync();
+
+            var credentials = GoogleGrpcCredentials.FromAccessToken(oauth2Token);
+            var request = new SimpleRequest
+            {
+                FillUsername = true,
+                FillOauthScope = true
+            };
+
+            var response = client.UnaryCall(request, new CallOptions(credentials: credentials));
+
+            Assert.False(string.IsNullOrEmpty(response.OauthScope));
+            Assert.True(oauthScope.Contains(response.OauthScope));
+            Assert.AreEqual(GetEmailFromServiceAccountFile(), response.Username);
+            Console.WriteLine("Passed!");
+        }
+
+        public static async Task RunPerRpcCredsAsync(TestService.TestServiceClient client, string oauthScope)
+        {
+            Console.WriteLine("running per_rpc_creds");
+            ITokenAccess googleCredential = await GoogleCredential.GetApplicationDefaultAsync();
+
+            var credentials = googleCredential.ToCallCredentials();
+            var request = new SimpleRequest
+            {
+                FillUsername = true,
+            };
+
+            var response = client.UnaryCall(request, new CallOptions(credentials: credentials));
+
+            Assert.AreEqual(GetEmailFromServiceAccountFile(), response.Username);
+            Console.WriteLine("Passed!");
+        }
+
+        public static async Task RunCancelAfterBeginAsync(TestService.ITestServiceClient client)
+        {
+            Console.WriteLine("running cancel_after_begin");
+
+            var cts = new CancellationTokenSource();
+            using (var call = client.StreamingInputCall(cancellationToken: cts.Token))
+            {
+                // TODO(jtattermusch): we need this to ensure call has been initiated once we cancel it.
+                await Task.Delay(1000);
+                cts.Cancel();
+
+                var ex = Assert.Throws<RpcException>(async () => await call.ResponseAsync);
+                Assert.AreEqual(StatusCode.Cancelled, ex.Status.StatusCode);
+            }
+            Console.WriteLine("Passed!");
+        }
+
+        public static async Task RunCancelAfterFirstResponseAsync(TestService.ITestServiceClient client)
+        {
+            Console.WriteLine("running cancel_after_first_response");
+
+            var cts = new CancellationTokenSource();
+            using (var call = client.FullDuplexCall(cancellationToken: cts.Token))
+            {
+                await call.RequestStream.WriteAsync(new StreamingOutputCallRequest
+                {
+                    ResponseType = PayloadType.COMPRESSABLE,
+                    ResponseParameters = { new ResponseParameters { Size = 31415 } },
+                    Payload = CreateZerosPayload(27182)
+                });
+
+                Assert.IsTrue(await call.ResponseStream.MoveNext());
+                Assert.AreEqual(PayloadType.COMPRESSABLE, call.ResponseStream.Current.Payload.Type);
+                Assert.AreEqual(31415, call.ResponseStream.Current.Payload.Body.Length);
+
+                cts.Cancel();
+
+                var ex = Assert.Throws<RpcException>(async () => await call.ResponseStream.MoveNext());
+                Assert.AreEqual(StatusCode.Cancelled, ex.Status.StatusCode);
+            }
+            Console.WriteLine("Passed!");
+        }
+
+        public static async Task RunTimeoutOnSleepingServerAsync(TestService.ITestServiceClient client)
+        {
+            Console.WriteLine("running timeout_on_sleeping_server");
+
+            var deadline = DateTime.UtcNow.AddMilliseconds(1);
+            using (var call = client.FullDuplexCall(deadline: deadline))
+            {
+                try
+                {
+                    await call.RequestStream.WriteAsync(new StreamingOutputCallRequest { Payload = CreateZerosPayload(27182) });
+                }
+                catch (InvalidOperationException)
+                {
+                    // Deadline was reached before write has started. Eat the exception and continue.
+                }
+
+                var ex = Assert.Throws<RpcException>(async () => await call.ResponseStream.MoveNext());
+                Assert.AreEqual(StatusCode.DeadlineExceeded, ex.Status.StatusCode);
+            }
+            Console.WriteLine("Passed!");
+        }
+
+        public static async Task RunCustomMetadataAsync(TestService.ITestServiceClient client)
+        {
+            Console.WriteLine("running custom_metadata");
+            {
+                // step 1: test unary call
+                var request = new SimpleRequest
+                {
+                    ResponseType = PayloadType.COMPRESSABLE,
+                    ResponseSize = 314159,
+                    Payload = CreateZerosPayload(271828)
+                };
+
+                var call = client.UnaryCallAsync(request, headers: CreateTestMetadata());
+                await call.ResponseAsync;
+
+                var responseHeaders = await call.ResponseHeadersAsync;
+                var responseTrailers = call.GetTrailers();
+
+                Assert.AreEqual("test_initial_metadata_value", responseHeaders.First((entry) => entry.Key == "x-grpc-test-echo-initial").Value);
+                CollectionAssert.AreEqual(new byte[] { 0xab, 0xab, 0xab }, responseTrailers.First((entry) => entry.Key == "x-grpc-test-echo-trailing-bin").ValueBytes);
+            }
+
+            {
+                // step 2: test full duplex call
+                var request = new StreamingOutputCallRequest
+                {
+                    ResponseType = PayloadType.COMPRESSABLE,
+                    ResponseParameters = { new ResponseParameters { Size = 31415 } },
+                    Payload = CreateZerosPayload(27182)
+                };
+
+                var call = client.FullDuplexCall(headers: CreateTestMetadata());
+                var responseHeaders = await call.ResponseHeadersAsync;
+
+                await call.RequestStream.WriteAsync(request);
+                await call.RequestStream.CompleteAsync();
+                await call.ResponseStream.ToListAsync();
+
+                var responseTrailers = call.GetTrailers();
+
+                Assert.AreEqual("test_initial_metadata_value", responseHeaders.First((entry) => entry.Key == "x-grpc-test-echo-initial").Value);
+                CollectionAssert.AreEqual(new byte[] { 0xab, 0xab, 0xab }, responseTrailers.First((entry) => entry.Key == "x-grpc-test-echo-trailing-bin").ValueBytes);
+            }
+
+            Console.WriteLine("Passed!");
+        }
+
+        public static async Task RunStatusCodeAndMessageAsync(TestService.ITestServiceClient client)
+        {
+            Console.WriteLine("running status_code_and_message");
+            var echoStatus = new EchoStatus
+            {
+                Code = 2,
+                Message = "test status message"
+            };
+
+            {
+                // step 1: test unary call
+                var request = new SimpleRequest { ResponseStatus = echoStatus };
+
+                var e = Assert.Throws<RpcException>(() => client.UnaryCall(request));
+                Assert.AreEqual(StatusCode.Unknown, e.Status.StatusCode);
+                Assert.AreEqual(echoStatus.Message, e.Status.Detail);
+            }
+
+            {
+                // step 2: test full duplex call
+                var request = new StreamingOutputCallRequest { ResponseStatus = echoStatus };
+
+                var call = client.FullDuplexCall();
+                await call.RequestStream.WriteAsync(request);
+                await call.RequestStream.CompleteAsync();
+
+                var e = Assert.Throws<RpcException>(async () => await call.ResponseStream.ToListAsync());
+                Assert.AreEqual(StatusCode.Unknown, e.Status.StatusCode);
+                Assert.AreEqual(echoStatus.Message, e.Status.Detail);
+            }
+
+            Console.WriteLine("Passed!");
+        }
+
+        public static void RunUnimplementedMethod(UnimplementedService.IUnimplementedServiceClient client)
+        {
+            Console.WriteLine("running unimplemented_method");
+            var e = Assert.Throws<RpcException>(() => client.UnimplementedCall(new Empty()));
+
+            Assert.AreEqual(StatusCode.Unimplemented, e.Status.StatusCode);
+            Assert.AreEqual("", e.Status.Detail);
+            Console.WriteLine("Passed!");
+        }
+
+        private static Payload CreateZerosPayload(int size)
+        {
+            return new Payload { Body = ByteString.CopyFrom(new byte[size]) };
+        }
+
+        // extracts the client_email field from service account file used for auth test cases
+        private static string GetEmailFromServiceAccountFile()
+        {
+            string keyFile = Environment.GetEnvironmentVariable("GOOGLE_APPLICATION_CREDENTIALS");
+            Assert.IsNotNull(keyFile);
+
+            var jobject = JObject.Parse(File.ReadAllText(keyFile));
+            string email = jobject.GetValue("client_email").Value<string>();
+            Assert.IsTrue(email.Length > 0);  // spec requires nonempty client email.
+            return email;
+        }
+
+        private static Metadata CreateTestMetadata()
+        {
+            return new Metadata
+            {
+                {"x-grpc-test-echo-initial", "test_initial_metadata_value"},
+                {"x-grpc-test-echo-trailing-bin", new byte[] {0xab, 0xab, 0xab}}
+            };
+        }
+    }
+}