python-2.7 - 在 Twisted 中关闭连接后退出 Python 程序

Question

所以我有这个小项目，它使用 python 中的 websockets 来自 autobahn twisted。客户端和服务器之间的连接以及数据传输工作正常，但在 TCP 连接关闭后我无法正常退出程序。她的是代码:

class MyClientProtocol(WebSocketClientProtocol):

    def onConnect(self, response):
        print("Server connected: {0}".format(response.peer))

    def onOpen(self):
        print("WebSocket connection open.")

        def hello():
            from twisted.internet import reactor
            self.sendMessage(u"Hello, world!".encode('utf8'))
            self.sendMessage(b"\x00\x01\x03\x04", isBinary=True)

            #self.factory.reactor.callLater(1, hello)
            #self.reactor.callFromThread(reactor.stop)
            #reactor.callFromThread(reactor.stop)
            #self.factory.reactor.callFromThread(reactor.stop)
        # start sending messages every second ..
        hello()
        return

    def onMessage(self, payload, isBinary):
        if isBinary:
            print("Binary message received: {0} bytes".format(len(payload)))
        else:
            print("Text message received: {0}".format(payload.decode('utf8')))

    def onClose(self, wasClean, code, reason):
        print("WebSocket connection closed: {0}".format(reason))


def WebCon():
    import sys

    from twisted.python import log
    from twisted.internet import reactor

    log.startLogging(sys.stdout)

    factory = WebSocketClientFactory("ws://localhost:8080", debug=False)
    factory.protocol = MyClientProtocol

    reactor.connectTCP("127.0.0.1", 8080, factory)

    reactor.run()
    reactor.stop()
    print("Should exit")
    return

Answer 1

reactor.run() 永远运行。所以这两行

reactor.run()
reactor.stop()

意思是:

Run forever. After "forever" is done, stop running.

在您提出问题的方式中有一个线索:您说您想“在 TCP 连接关闭 后优雅地[退出]程序”。由于您现在正在编写程序，因此您可以在程序准备好退出后优雅地退出程序。

连接关闭是一个事件。在 Twisted 中，通过在对象上调用的方法通知您事件。幸运的是，您已经获得了对象，甚至已经实现了适当的方法!你只需要改变

def onClose(self, wasClean, code, reason):
    print("WebSocket connection closed: {0}".format(reason))

到

def onClose(self, wasClean, code, reason):
    print("WebSocket connection closed: {0}".format(reason))
    reactor.stop()

对于更惯用的解决方案，您真的应该使用 endpoints ，而不是 connectTCP，以建立传出连接，并且 react ，而不是 reactor.run()，来运行您的主循环。看起来您想编写一个函数，读起来更像是“连接，然后在我的连接上做一些事情，然后等待连接关闭，然后退出”，而不是硬编码 onClose 来停止整个 react 堆。

那看起来更像这样: 导入系统 从某处.i.dont.know 导入(WebSocketClientProtocol， WebSocketClientFactory)

from twisted.internet.defer import Deferred, inlineCallbacks
from twisted.internet.task import react
from twisted.internet.endpoints import clientFromString

from twisted.logger import globalLogBeginner, textFileLogObserver

class MyClientProtocol(WebSocketClientProtocol):

    def __init__(self):
        self.finished = Deferred()

    def onConnect(self, response):
        print("Server connected: {0}".format(response.peer))

    def onOpen(self):
        print("WebSocket connection open.")
        self.sendMessage(u"Hello, world!".encode('utf8'))
        self.sendMessage(b"\x00\x01\x03\x04", isBinary=True)

    def onMessage(self, payload, isBinary):
        if isBinary:
            print("Binary message received: {0} bytes".format(len(payload)))
        else:
            print("Text message received: {0}".format(payload.decode('utf8')))

    def onClose(self, wasClean, code, reason):
        print("WebSocket connection closed: {0}".format(reason))
        self.finished.callback(None)


@inlineCallbacks
def WebCon(reactor, endpoint="tcp:127.0.0.1:80"):
    globalLogBeginner.beginLoggingTo(textFileLogObserver(sys.stdout))

    factory = WebSocketClientFactory("ws://localhost:8080", debug=False)
    factory.protocol = MyClientProtocol

    endpoint = clientFromString(reactor, endpoint)
    protocol = yield endpoint.connect(factory)
    yield protocol.finished

react(WebCon, sys.argv[1:])

希望这对您有所帮助!