QWebSocket 无法处理握手

Question

我在使用 QWebSocket 建立 WebSocket 连接时遇到问题。我正在使用 Qt 5.6 及其 QWebSocket 实现。我确信服务器工作正常并使用 WS v13 协议。它适用于所有浏览器。当我尝试连接到服务器时，QWebSocket 使用这些消息发出 error 和 stateChanged 信号（我使用 errorString() 方法获取它们）：

QWebSocketPrivate::processHandshake: Connection closed while reading header.
Invalid statusline in response: Upgrade: websocket
Invalid statusline in response: Connection: Upgrade
Invalid statusline in response: Sec-WebSocket-Accept: HLaITyncgax+CH7OUIXnsCfFDDY=
Invalid statusline in response: // there's a carriage return symbol

虽然它说Connection closed while reading header，但连接实际上并没有关闭（因为服务器在一段时间后通过 websocket 发送额外的数据包）。我已经在 websocket.org 的回声测试中测试了我的应用程序，它工作正常！但我在两次尝试中都嗅探了数据包，没有发现任何显着差异。

我尝试连接的服务器上的数据包嗅探结果：

GET / HTTP/1.1
Host: <hostname>:6670
Upgrade: websocket
Connection: Upgrade
Sec-WebSocket-Key: WcIsYc1AZ6CKikXFwGXgMg==
Origin: http://<hostname>
Sec-WebSocket-Version: 13
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Firefox/45.0
Connection: keep-alive, Upgrade


HTTP/1.1 101 Switching Protocols
Upgrade: websocket
Connection: Upgrade
Sec-WebSocket-Accept: 7lfSGmSz/eW1mSzaMnuzOqg00w4=

与 echo.websocket.org 连接时数据包嗅探的结果：

GET / HTTP/1.1
Host: echo.websocket.org:80
Upgrade: websocket
Connection: Upgrade
Sec-WebSocket-Key: MUAZoP0Ef4KSWkmtsB5YDw==
Origin: http://<hostname>
Sec-WebSocket-Version: 13
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Firefox/45.0
Connection: keep-alive, Upgrade


HTTP/1.1 101 Web Socket Protocol Handshake
Access-Control-Allow-Credentials: true
Access-Control-Allow-Headers: content-type
Access-Control-Allow-Headers: authorization
Access-Control-Allow-Headers: x-websocket-extensions
Access-Control-Allow-Headers: x-websocket-version
Access-Control-Allow-Headers: x-websocket-protocol
Access-Control-Allow-Origin: http://<hostname>
Connection: Upgrade
Date: Thu, 31 Mar 2016 12:05:49 GMT
Sec-WebSocket-Accept: c4yAe+A1VRuhF1LSC/TGgPoa8N4=
Server: Kaazing Gateway
Upgrade: websocket

<data exchange goes here normally>

我应该如何调查和解决问题？我无法访问服务器。

P.S。是的，我知道 QTBUG-40878。它会影响 Qt 5.3.1，但我使用 5.6.0，它显然已在我的 Qt 设置中得到修复。

Answer 1

这可能是QTBUG-51069（不是你说的那个）：

If there is a delay between status line ("HTTP/1.1 101 Upgrading Protocol") and headers, QWebSocketPrivate::processHandshake erroneously detects server disconnect. The problem is that disconnect condition is checked using QAbstractSocket::atEnd function which just checks if data available and not the actual socket state. This results in multiple error signals:
websocket error: QWebSocket::processHandshake: Connection closed while reading header.
websocket error: Invalid statusline in response: Date: Thu, 11 Feb 2016 20:07:37 GMT^M .
websocket error: Invalid statusline in response: Server: WSGIServer/0.1 Python/2.7.10^M .
websocket error: Invalid statusline in response: Upgrade: websocket^M .
websocket error: Invalid statusline in response: Connection: Upgrade^M .
websocket error: Invalid statusline in response: Sec-WebSocket-Accept: oQ+NK56UdGrsXFisB9chjE3SU+Y=^M .
websocket error: Invalid statusline in response: Sec-WebSocket-Version: 13^M .
websocket error: Invalid statusline in response: Content-Length: 0^M .
websocket error: Invalid statusline in response: ^M .

修复在 Qt 5.6.2 中。

对于Qt 5.7，从commit history来看我认为它将在5.7.1中。

QWebSocket 无法处理握手

QWebSocket can't process the handshake

c++

qt

websocket

qtwebsockets