如何将 HTTP 请求升级到 Websocket（高速公路和扭曲网络）

Question

为了让您了解我正在尝试使用 Twisted Web 和 Autobahn websockets 完成什么：我的 UI 当前发送一个初始 HTTP GET 请求，并升级到 header 中的 websocket .在 Twisted Web 中读取该内容后，连接需要从 HTTP 切换到 websocket 协议以来回传递数据。请注意，此 websocket 升级发生在同一端口 port 8000。

有谁知道我如何实现我想做的事情？非常感谢。

编辑：工作示例的更新代码。您可以在这里找到它：Payload from POST Request is Cutoff (Twisted Web)

这是我使用 Twisted Web 的代码：

class HttpResource(resource.Resource):
    isLeaf = 1

    def __init__(self):
        self.children = {}
        self.ws_port = None

    print 'resource invoked'
    def render_GET(self, request):

        print 'render invoked'
        if request.getHeader('Sec-WebSocket-Key'):
            # Processing the Key as per RFC 6455
            key = request.getHeader('Sec-WebSocket-Key')
            h = hashlib.sha1(key + "258EAFA5-E914-47DA-95CA-C5AB0DC85B11")
            request.setHeader('Sec-WebSocket-Accept', base64.b64encode(h.digest()))

            # setting response headers
            request.setHeader('Upgrade', 'websocket')
            request.setHeader('Connection', 'Upgrade')
            request.setResponseCode(101)
            return ''
        else:
            log("Regular HTTP GET request.")
            return "<html><body style='margin: 0; overflow: hidden;'><iframe style='width: 100%; height: 100%; border: none;' src='http://tsa-graphiql.herokuapp.com/'></iframe></body></html>"

    def render_POST(self,request):
        log("POST request")
        request.setResponseCode(200)

    def handle_single_query(self, queryData):
        log("Handle single query data.")
        return


class HttpWsChannel(http.HTTPChannel):

    def dataReceived(self, data):
        log('Data received:\n{}'.format(data))
        if data.startswith('GET'):
            # This will invoke the render method of resource provided
            http.HTTPChannel.dataReceived(self, data)
        if data.startswith('POST'):
            http.HTTPChannel.dataReceived(self, data)
        else:
            """
            Pass binary data to websocket class.
            """
            ws_protocol = self.site.ws_factory.protocol(self.site.ws_factory.connection_subscriptions)
            log(ws_protocol)
            #just echo for now
            # self.transport.write(data)


class HttpFactory(Site):
    """
    Factory which takes care of tracking which protocol
    instances or request instances are responsible for which
    named response channels, so incoming messages can be
    routed appropriately.
    """

    def __init__(self, resource):
        http.HTTPFactory.__init__(self)
        self.resource = resource
        self.ws_factory = WsProtocolFactory("ws://127.0.0.1:8000")
        self.ws_factory.protocol = WsProtocol

    def buildProtocol(self, addr):
        try:
            channel = HttpWsChannel()
            channel.requestFactory = self.requestFactory
            channel.site = self
            return channel
        except Exception as e:
            log("Could not build protocol: {}".format(e))

site = HttpFactory(HttpResource())

if __name__ == '__main__':
    reactor.listenTCP(8000, site)
    reactor.run()

编辑 7/8/2017：这是我在下面尝试的新代码。通过 onMessage 方法成功接收到 websocket 消息。但是 HTTP 请求不起作用。我在 GET 请求中遇到的当前错误是：

<html>
  <head><title>404 - No Such Resource</title></head>
  <body>
    <h1>No Such Resource</h1>
    <p>No such child resource.</p>
  </body>
</html>

Python代码

from twisted.web.server import (
    Site,
)
from twisted.internet import reactor
from twisted.web.resource import (
    Resource,
)
from autobahn.twisted.websocket import (
    WebSocketServerProtocol,
    WebSocketServerFactory,
)
from autobahn.twisted.resource import (
    WebSocketResource,
)


class WebSocketProtocol(WebSocketServerProtocol):

    def onConnect(self, request):
        print("WebSocket connection request: {}".format(request))

    def onMessage(self, payload, isBinary):
        print("onMessage: {}".format(payload))


if __name__ == '__main__':

    factory = WebSocketServerFactory()
    factory.protocol = WebSocketProtocol
    resource = WebSocketResource(factory)

    root = Resource()
    root.putChild(b"ws", resource)

    site = Site(root)
    reactor.listenTCP(8000, site)

    reactor.run()

Answer 1

使用 WebSocketResource 公开 WebSocketServerFactory 作为 Site 的一部分。

from twisted.web.server import (
    Site,
)
from twisted.web.resource import (
    Resource,
)
from autobahn.twisted.websocket import (
    WebSocketServerProtocol,
    WebSocketServerFactory,
)
from autobahn.twisted.resource import (
    WebSocketResource,
)

class YourAppProtocol(WebSocketServerProtocol):
    def onConnect(self, request):
        ...

    ...

def main():
    factory = WebSocketRendezvousFactory()
    factory.protocol = YourAppProtocol
    resource = WebSocketResource(factory)
    root = Resource()
    root.putChild(b"some-path-segment", resource)
    root.putChild(...)
    site = Site(root)
    reactor.listenTCP(8080, site)
    reactor.run()

请求正文被截断的问题可能是因为您的升级协议实现有问题。 dataReceived 级别没有应用框架，因此您不能指望像 startswith("GET") 这样的检查是可靠的。

使用 WebSocketResource 和 Site 为您提供来自 Twisted Web 和 Autobahn 的正确 HTTP 解析代码，同时还允许您将 WebSocket 与特定的 URL 和常规 HTTP 对话。

Answer 2

所以在 Google 上阅读了一些内容后，我发现这个网站解释了如何通过 Autobahn Twisted 将 HTTP 连接升级为 websocket 连接：Read and Set request headers via Autobahn Twisted.

我能够开始工作的代码如下所示！

from twisted.web.server import (
    Site,
)
from twisted.internet import reactor
from twisted.web.resource import (
    Resource,
)
from autobahn.twisted.websocket import (
    WebSocketServerProtocol,
    WebSocketServerFactory,
)
from autobahn.twisted.resource import (
    WebSocketResource,
)


class HttpResource(Resource):
    isLeaf = True

    def render_GET(self, request):
    return "<html><body style='margin: 0; overflow: hidden;'><iframe style='width: 100%; height: 100%; border: none;' src='http://tsa-graphiql.herokuapp.com/'></iframe></body></html>"


class WebSocketProtocol(WebSocketServerProtocol):

    def onConnect(self, request):
        custom_header = {}

        if request.headers['sec-websocket-key']:
            custom_header['sec-websocket-protocol'] = 'graphql-ws'
        return (None, custom_header)

    def onMessage(self, payload, isBinary):
        print("onMessage: {}".format(payload))


if __name__ == '__main__':

    factory = WebSocketServerFactory()
    factory.protocol = WebSocketProtocol
    resource = WebSocketResource(factory)

    root = Resource()
    root.putChild("", HttpResource())
    root.putChild(b"ws", ws_resource)

    site = Site(root)
    reactor.listenTCP(8000, site)

如何将 HTTP 请求升级到 Websocket（高速公路和扭曲网络）

How to Upgrade HTTP Request to Websocket (Autobahn & Twisted Web )

python

twisted

websocket

twisted.web

autobahn