用于单元测试的模拟 gRPC 响应流 - C#

如何解决用于单元测试的模拟 gRPC 响应流 - C#

我有一个函数可以调用 gRPC 端点，将对象转换为 POCO 对象并将它们作为列表返回。

public class ActionPlanConnectionsService : IConnectionService
    {
            #region Fields
    
            /// <summary>
            /// Grpc client
            /// </summary>
            private readonly ConnectionDb.ConnectionDbClient _client;
            #endregion
    
            public ActionPlanConnectionsService(ConnectionDb.ConnectionDbClient channel)
            {
                _client = channel;
            }
    
            public async Task<IEnumerable<Connection>> Get(int actionPlanId,int implementation)
            {
               List<Connection> diagramConnections = new List<Connection>();
               GetConnectionsByIdAndImplementationMessage message = new GetConnectionsByIdAndImplementationMessage
               {
                   ActionPlanId = actionPlanId,Implementation = implementation
               };
    
               using var call = _client.GetAllConnections(message);
               await foreach (ConnectionServiceModel connection in call.ResponseStream.ReadAllAsync())
               {
                   // Never enters here as ResponseStream has no elements when unit testing!!
                   diagramConnections.Add(new Connection(
                       connection.FromActionPlanStepId,connection.ToActionPlanStepId,connection.ActionPlanId,connection.Qualifier,connection.Implementation,connection.Path));
               }
    
               return diagramConnections;
           }
   }

我一直在为此函数开发单元测试，但返回的列表的计数始终为零。 这是因为 ResponseStream 里面没有元素。

如何模拟 ResponseStream？

到目前为止我的单元测试：

[Test]
        public async Task GetConnectionstest()
        {
            // Arrange
            Mock<ConnectionDb.ConnectionDbClient> mockClient = new Mock<ConnectionDb.ConnectionDbClient>();
            Mock<IAsyncStreamReader<ConnectionServiceModel>> mockResponseStream
                = new Mock<IAsyncStreamReader<ConnectionServiceModel>>();

            List<ConnectionServiceModel> connectionServiceModels =
                new List<ConnectionServiceModel>
                {
                    new ConnectionServiceModel
                    {
                        ActionPlanId = 1,FromActionPlanStepId = 1,ToActionPlanStepId = 1,Implementation = 0,Qualifier = 1,Path = " 1;2;3;4;5;6;7;8;9;10;11;12;13;14"
                    }
                };

            var fakeCall = TestCalls.AsyncServerStreamingCall
                (mockResponseStream.Object,Task.Fromresult(new Metadata()),() => Status.DefaultSuccess,() => new Metadata(),() => { });

            mockClient.Setup(m => m.GetAllConnections(
                It.IsAny<GetConnectionsByIdAndImplementationMessage>(),null,CancellationToken.None)).Returns(fakeCall);

            // Act
            ActionPlanConnectionsService service = new ActionPlanConnectionsService(mockClient.Object);
            IEnumerable<Connection> connections = await service.Get(1,1);

            // Assert
            
            // CONNECTIONS WILL ALWAYS HAVE 0 Elements as the response isn't setup for it.
        }
    }