我正在尝试一个新的NServiceBus项目,该项目使用Azure存储队列来进行消息传输和JSON序列化,并使用自定义消息展开逻辑,如下所示:
var jsonSerializer = new Newtonsoft.Json.JsonSerializer();
transportExtensions.UnwrapMessagesWith(cloudQueueMessage =>
{
using (var stream = new MemoryStream(cloudQueueMessage.AsBytes))
using (var streamReader = new StreamReader(stream))
using (var textReader = new JsonTextReader(streamReader))
{
try
{
var jObject = JObject.Load(textReader);
using (var jsonReader = jObject.CreateReader())
{
// Try deserialize to a NServiceBus envelope first
var wrapper = jsonSerializer.Deserialize<MessageWrapper>(jsonReader);
if (wrapper.MessageIntent != default)
{
// This was a envelope message
return wrapper;
}
}
// Otherwise this was an EventGrid event
using (var jsonReader = jObject.CreateReader())
{
var @event = jsonSerializer.Deserialize<EventGridEvent>(jsonReader);
var wrapper = new MessageWrapper
{
Id = @event.Id,
Headers = new Dictionary<string, string>
{
{ "NServiceBus.EnclosedMessageTypes", @event.EventType },
{ "NServiceBus.MessageIntent", "Publish" },
{ "EventGrid.topic", @event.Topic },
{ "EventGrid.subject", @event.Subject },
{ "EventGrid.eventTime", @event.EventTime.ToString("u") },
{ "EventGrid.dataVersion", @event.DataVersion },
{ "EventGrid.metadataVersion", @event.MetadataVersion },
},
Body = Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(@event.Data)),
MessageIntent = MessageIntentEnum.Publish
};
return wrapper;
}
}
catch
{
logger.Error("Message deserialization failed, sending message to error queue");
throw;
}
}
});
自定义消息展开逻辑对于格式正确的JSON消息正确工作,当将格式不正确的JSON消息放入输入队列时,自定义消息展开逻辑将在使用情况的第一行出错,在该行中我创建了jObject,即预期的行为。但是,当自定义消息展开逻辑失败时,该错误将被MessageRetrieved类中的逻辑捕获,该类是NServiceBus.Azure.Transports.WindowsAzureStorageQueues NuGet包(v8.2.0)的一部分,如下所示:
public async Task<MessageWrapper> Unwrap()
{
try
{
Logger.DebugFormat("Unwrapping message with native ID: '{0}'", rawMessage.Id);
return unwrapper.Unwrap(rawMessage);
}
catch (Exception ex)
{
await errorQueue.AddMessageAsync(rawMessage).ConfigureAwait(false);
await inputQueue.DeleteMessageAsync(rawMessage).ConfigureAwait(false);
throw new SerializationException($"Failed to deserialize message envelope for message with id {rawMessage.Id}. Make sure the configured serializer is used across all endpoints or configure the message wrapper serializer for this endpoint using the `SerializeMessageWrapperWith` extension on the transport configuration. Please refer to the Azure Storage Queue Transport configuration documentation for more details.", ex);
}
}
尝试捕获的第一行正常运行,将消息添加到已配置的错误队列中,但是,这样做时,它似乎正在更改原始消息的消息ID和popreceipt,如下所示:
然后,当下一行尝试从输入队列中删除原始消息时,它无法找到它,因为根据本文https://docs.microsoft.com/en-us/rest/api/storageservices/delete-message2#remarks,它需要原始消息ID和pop接收器,它们现在已更改,从而导致以下错误被抛出:
2020-04-20 14:17:58,603 WARN : Azure Storage Queue transport failed pushing a message through pipeline
Type: Microsoft.WindowsAzure.Storage.StorageException
Message: The remote server returned an error: (404) Not Found.
Source: Microsoft.WindowsAzure.Storage
StackTrace:
at Microsoft.WindowsAzure.Storage.Core.Executor.Executor.EndExecuteAsync[T](IAsyncResult result) in c:\Program Files (x86)\Jenkins\workspace\release_dotnet_master\Lib\ClassLibraryCommon\Core\Executor\Executor.cs:line 50
at Microsoft.WindowsAzure.Storage.Core.Util.AsyncExtensions.<>c__DisplayClass7.<CreateCallbackVoid>b__5(IAsyncResult ar) in c:\Program Files (x86)\Jenkins\workspace\release_dotnet_master\Lib\ClassLibraryCommon\Core\Util\AsyncExtensions.cs:line 121
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at NServiceBus.Transport.AzureStorageQueues.MessageRetrieved.<Unwrap>d__3.MoveNext() in C:\BuildAgent\work\3c19e2a032c05076\src\Transport\MessageRetrieved.cs:line 40
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at NServiceBus.Transport.AzureStorageQueues.MessagePump.<InnerReceive>d__7.MoveNext() in C:\BuildAgent\work\3c19e2a032c05076\src\Transport\MessagePump.cs:line 153
TargetSite: T EndExecuteAsync[T](System.IAsyncResult)
这是NServiceBus软件包逻辑的问题,还是我的自定义消息展开逻辑中的某些问题导致这些值发生更改?
这是一个错误。当展开失败时,该消息尚未通过处理管道。结果,正常的可恢复性不适用。 CloudQueueMessage
需要被“克隆”,并将克隆发送到错误队列,而原始消息用于将其从输入队列中删除。我在GitHub上提出了bug issue,您可以在此跟踪该过程。