如何为ProxyAgent设置超时？

Question

client.Agent类有一个连接超时参数：

agent = client.Agent(reactor, connectTimeout=timeout, pool=pool)

如何在使用client.ProxyAgent时设置此超时

auth = base64.b64encode("%s:%s" % (username, password))
headers['Proxy-Authorization'] = ["Basic " + auth.strip()]
endpoint = endpoints.TCP4ClientEndpoint(reactor, host, port)
agent = client.ProxyAgent(endpoint, reactor=reactor, pool=pool)

Answer 1

传递给TCP4ClientEndpoint的ProxyAgent可以通过超时进行初始化。

auth = base64.b64encode("%s:%s" % (username, password))
headers['Proxy-Authorization'] = ["Basic " + auth.strip()]
endpoint = endpoints.TCP4ClientEndpoint(reactor, host, port, timeout=yourTimeout)
agent = client.ProxyAgent(endpoint, reactor=reactor, pool=pool)

这是假设您希望设置连接到代理的超时。如果希望设置代理用于连接到上游HTTP服务器的超时，则无法控制此超时。

Answer 2

看起来client.ProxyAgent没有connectTimeout属性：

class ProxyAgent(_AgentBase):
    """
    An HTTP agent able to cross HTTP proxies.

    @ivar _proxyEndpoint: The endpoint used to connect to the proxy.

    @since: 11.1
    """

    def __init__(self, endpoint, reactor=None, pool=None):
        if reactor is None:
            from twisted.internet import reactor
        _AgentBase.__init__(self, reactor, pool)
        self._proxyEndpoint = endpoint


    def request(self, method, uri, headers=None, bodyProducer=None):
        """
        Issue a new request via the configured proxy.
        """
        # Cache *all* connections under the same key, since we are only
        # connecting to a single destination, the proxy:
        key = ("http-proxy", self._proxyEndpoint)

        # To support proxying HTTPS via CONNECT, we will use key
        # ("http-proxy-CONNECT", scheme, host, port), and an endpoint that
        # wraps _proxyEndpoint with an additional callback to do the CONNECT.
        return self._requestWithEndpoint(key, self._proxyEndpoint, method,
                                         _URI.fromBytes(uri), headers,
                                         bodyProducer, uri)

ProxyAgent继承的是Agent not (_AgentBase)类，而不是Agent本身。