Improve tester example to log errors and have non-success test (#1841)

Author: JamesNK

examples/Tester/Server/Startup.cs

@@ -27,7 +27,7 @@ public class Startup
     {
         public void ConfigureServices(IServiceCollection services)
         {
-            services.AddGrpc();
+            services.AddGrpc(o => o.EnableDetailedErrors = true);
             services.AddSingleton<IGreeter, Greeter>();
         }
 

examples/Tester/Tests/Server/IntegrationTests/Helpers/GrpcTestContext.cs

@@ -44,7 +44,12 @@ private void WriteMessage(LogLevel logLevel, string category, EventId eventId, s
             // if it is written in the test's execution context.
             ExecutionContext.Run(_executionContext, s =>
             {
-                Console.WriteLine($"{_stopwatch.Elapsed.TotalSeconds:N3}s {category} - {logLevel}: {message}");
+                var log = $"{_stopwatch.Elapsed.TotalSeconds:N3}s {category} - {logLevel}: {message}";
+                if (exception != null)
+                {
+                    log += Environment.NewLine + exception.ToString();
+                }
+                Console.WriteLine(log);
             }, null);
         }
 

examples/Tester/Tests/Server/IntegrationTests/MockedGreeterServiceTests.cs

@@ -16,6 +16,7 @@
 
 #endregion
 
+using Grpc.Core;
 using Microsoft.Extensions.DependencyInjection;
 using Moq;
 using NUnit.Framework;
@@ -30,13 +31,20 @@ protected override void ConfigureServices(IServiceCollection services)
         {
             var mockGreeter = new Mock<IGreeter>();
             mockGreeter.Setup(
-                m => m.Greet(It.IsAny<string>())).Returns((string s) => $"Test {s}");
+                m => m.Greet(It.IsAny<string>())).Returns((string s) =>
+                {
+                    if (string.IsNullOrEmpty(s))
+                    {
+                        throw new ArgumentException("Name not provided.");
+                    }
+                    return $"Test {s}";
+                });
 
             services.AddSingleton(mockGreeter.Object);
         }
 
         [Test]
-        public async Task SayHelloUnaryTest_MockGreeter()
+        public async Task SayHelloUnaryTest_MockGreeter_Success()
         {
             // Arrange
             var client = new Tester.TesterClient(Channel);
@@ -48,5 +56,24 @@ public async Task SayHelloUnaryTest_MockGreeter()
             // Assert
             Assert.AreEqual("Test Joe", response.Message);
         }
+
+        [Test]
+        public async Task SayHelloUnaryTest_MockGreeter_Error()
+        {
+            // Arrange
+            var client = new Tester.TesterClient(Channel);
+
+            // Act
+            try
+            {
+                await client.SayHelloUnaryAsync(new HelloRequest { Name = "" });
+                Assert.Fail();
+            }
+            catch (RpcException ex)
+            {
+                // Assert
+                StringAssert.Contains("Name not provided.", ex.Status.Detail);
+            }
+        }
     }
 }