如何将HTTP请求升级到Websocket（Autobahn＆Twisted Web）
问题描述：
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websocket在标题中。在Twisted Web中读取时，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上，port 8000。如何将HTTP请求升级到Websocket（Autobahn＆Twisted Web）
有谁知道我可以如何实现我想要做的？非常感谢。
编辑：工作示例的更新代码。你可以在这里找到它：Payload from POST Request is Cutoff (Twisted Web)
下面是使用双绞线网络我的代码：
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2017年7月8日：这里是我的尝试下面的新代码。 websocket消息通过onMessage方法成功接收。但是HTTP请求不起作用。当前的错误，我在一个GET请求得到的是：
<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()
答
因此，在Google上稍微阅读一下后，我发现这个网站介绍了如何通过Autobahn Twisted：Read and Set request headers via Autobahn Twisted将HTTP连接升级到websocket连接。
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)
答
使用WebSocketResource，露出一个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()
截断的请求主体的问题可能是因为您的升级协议实现有问题。在dataReceived的级别上没有应用框架，因此您不能期望像startswith("GET")这样的检查是可靠的。
使用WebSocketResource和Site让你从扭曲的Web和高速公路正确的HTTP解析代码，同时还允许你说话的WebSocket到一个特定的URL和普通的HTTP给他人。
我不认为这段代码展示了如何在与HTTP相同的端口上使用autobahn websocket。我之前已经实现了这个代码，这不是我想要的。我相信我可能有一个使用扭曲网络库的工作示例 – Brian
我已经使用指向正在运行的示例的链接更新了描述，但遇到请求被截断的问题。仍在深入研究这个问题@ jean-paul-calderone – Brian
谢谢！我试过你的例子，我能够接收websocket消息。然而，当我执行一个GET请求时，我得到了一个404，说明没有这样的资源 - 找不到这样的子资源。 – Brian