用Twisted阻止Thrift通話

Question

我有一個使用TTwisted協議的Twisted / Thrift服務器。 我希望保持客戶端的連接打開，直到發生給定事件（Twisted反應堆通過回調通知我此事件）。

class ServiceHandler(object):
    interface.implements(Service.Iface)

    def listenForEvent(self):
        """
        A method defined in my Thrift interface that should block the Thrift
        response until my event of interest occurs.
        """
        # I need to somehow return immediately to free up the reactor thread,
        # but I don't want the Thrift call to be considered completed. The current
        # request needs to be marked as "waiting" somehow.

    def handleEvent(self):
        """
        A method called when the event of interest occurs. It is a callback method
        registered with the Twisted reactor.
        """
        # Find all the "waiting" requests and notify them that the event occurred.
        # This will cause all of the Thrift requests to complete.

如何在保持阻塞Thrift調用的錯覺的同時快速從我的處理程序對象的方法返回？

---

我從Twisted啟動觸發器初始化Thrift處理程序：

def on_startup():
    handler = ServiceHandler()                      
    processor = Service.Processor(handler)                                   
    server = TTwisted.ThriftServerFactory(processor=processor,                  
        iprot_factory=TBinaryProtocol.TBinaryProtocolFactory())                 
    reactor.listenTCP(9160, server)

我的PHP客戶端連接：

  $socket = new TSocket('localhost', 9160);
  $transport = new TFramedTransport($socket);
  $protocol = new TBinaryProtocol($transport);
  $client = new ServiceClient($protocol);
  $transport->open();
  $client->listenForEvent();

最后一個調用（ $client->listenForEvent() ）成功將其轉移到服務器並運行ServiceHandler.listenForEvent ，但是即使該服務器方法返回twisted.internet.defer.Deferred()實例，客戶端也將立即收到一個空數組，我得到異常：

異常'TTransportException'，消息'TSocket：timed out read 4 bytes from localhost：9160 to local port 38395'

Answer 1

您應該能夠從listenForEvent返回Deferred。 稍后handleEvent應該觸發返回的Deferred（或那些返回的Deferreds）來實際生成響應。

Answer 2

您看到的錯誤似乎表明傳輸沒有框架（Twisted需要這樣，以便它可以事先知道每條消息的長度）。 此外，Thrift服務器支持從處理程序返回延遲，因此更奇怪。 您是否嘗試過返回defer.succeed（“某些值”）並查看延遲實際是否有效？ 然后，您可以轉到此位置以檢查它是否可以正常運行：

    d = defer.Deferred()
    reactor.callLater(0, d.callback, results)
    return d