我正在尝试使用nservicebus和rabbitmq进行多个连续的请求。这是我的代码
class Program
{
static void Main(string[] args)
{
MainAsync().GetAwaiter().GetResult();
}
static async Task MainAsync()
{
ConfigureLog();
var ec = new EndpointConfiguration("NServiceBus.RequestResponse");
ec.UsePersistence<InMemoryPersistence>();
ec.EnableInstallers();
ec.EnableCallbacks();
ec.MakeInstanceUniquelyAddressable(Guid.NewGuid().ToString());
ec.LimitMessageProcessingConcurrencyTo(1);
var transport = ec.UseTransport<RabbitMQTransport>();
transport.UseConventionalRoutingTopology();
transport.ConnectionString("host=localhost;username=guest;password=guest");
transport.PrefetchCount(100);
var endpoint = await Endpoint.Start(ec)
.ConfigureAwait(false);
try
{
var options = new SendOptions();
options.SetDestination("NServiceBus.RequestResponse");
Log($"Sending message: 1");
var response1 = await endpoint.Request<MyResponse>(new MyMessage() { Text = "Hello World!!" }, options);
Log($"Response 1 : {response1.Text}");
Log($"Sending message: 2");
var response2 = await endpoint.Request<MyResponse>(new MyMessage() { Text = "Hello from second request!!" }, options);
Log($"Response 1 : {response2.Text}");
}
catch (Exception e)
{
Log("#### ERROR ####");
Log(e.Message);
Log(e.StackTrace);
}
finally
{
await endpoint.Stop()
.ConfigureAwait(false);
}
Console.WriteLine("Press any key to exit");
Console.ReadKey();
}
private static void Log(string msg)
{
LogManager.GetLogger("NServiceBus.RequestResponse").Debug(msg);
Console.WriteLine(msg);
}
private static void ConfigureLog()
{
var layout = new PatternLayout
{
ConversionPattern = "%d [%t] %-5p %c [%x] - %m%n"
};
layout.ActivateOptions();
var consoleAppender = new ConsoleAppender
{
Threshold = Level.All,
Layout = layout
};
consoleAppender.ActivateOptions();
var fileAppender = new FileAppender()
{
Threshold = Level.All,
Layout = layout,
File = "nsb_log.txt"
};
fileAppender.ActivateOptions();
var executingAssembly = Assembly.GetExecutingAssembly();
var repository = log4net.LogManager.GetRepository(executingAssembly);
BasicConfigurator.Configure(repository, consoleAppender, fileAppender);
LogManager.Use<Log4NetFactory>();
}
}
public class MyMessage : IMessage
{
public string Text { get; set; }
}
public class MyMessageHandler : IHandleMessages<MyMessage>
{
public async Task Handle(MyMessage message, IMessageHandlerContext context)
{
await Console.Out.WriteLineAsync($"Message [{context.MessageId}] received: {message.Text} ");
await context.Reply(new MyResponse() { Text = "Hi There!!" });
}
}
public class MyResponse : IMessage
{
public string Text { get; set; }
}
运行程序时,我将获得以下第二个请求的例外:
2019-02-25 11:03:22,800 [9] DEBUG NServiceBus.RequestResponse [(null)] - Already specified reply routing option for this message: RouteReplyToThisInstance
2019-02-25 11:03:22,811 [9] DEBUG NServiceBus.RequestResponse [(null)] - at NServiceBus.ApplyReplyToAddressBehavior.State.set_Option(RouteOption value)
at NServiceBus.RoutingOptionExtensions.RouteReplyToThisInstance(SendOptions options)
at NServiceBus.RequestResponseExtensions.<Request>d__3`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
at NServiceBus.RequestResponse.Program.<MainAsync>d__1.MoveNext() in C:UserscruzedusourcereposNServiceBus.RequestResponseNServiceBus.RequestResponseProgram.cs:line 47
我知道我可以更改代码以调用发送方法并为响应提供处理程序,但是我仍然不明白为什么它不适用于请求。我需要做什么才能使它工作?
我尝试设置消息ID,而不是在第二个呼叫上传递发送选项,等等。似乎没有用。我认为这可能是一个错误。
我创建了一个示例项目来重现该行为并在Github上共享。链接在这里。重要的是要指出它需要一个兔子实例。就我而言,我将其在本地设置(http://localhost:15672),默认访客用户/密码。
您每次发送消息时都需要初始化一个新的sendoptions副本,因为您无法重复使用以前的副本。
var options = new SendOptions();
options.SetDestination("NServiceBus.RequestResponse");
var response1 = await endpoint.Request<MyResponse>(new MyMessage() { Text = "Hello World!!" }, options);
options = new SendOptions();
options.SetDestination("NServiceBus.RequestResponse");
var response2 = await endpoint.Request<MyResponse>(new MyMessage() { Text = "Hello from second request!!" }, options);