Question

我尝试通过websocket和polling运行我的socket.io程序，它们都有效。然而，当试图通过xhr-polling时，它会超时。可能的原因是什么？

对于这个程序，我使用的是socket.io 1.2.1。

var options = {"force new connection":true,
               "reconnect":false,
               "connect timeout":10000,
               "flash policy port":843,
               "auto connect":true,
               "path":"/sample/socket.io",
               "transports":["xhr-polling"]}

this.namespace = io.connect( 'http://localhost:8190/', options);

到目前为止，我的研究对此问题一无所知。

编辑：

这是浏览器上的一段日志。

socket.io-client:url parse http://localhost:8190/ +0ms
socket.io.js:1284 socket.io-client ignoring socket cache for http://localhost:8190/ +0ms
socket.io.js:1284 socket.io-client:manager readyState closed +0ms
socket.io.js:1284 socket.io-client:manager opening http://localhost:8190/ +0ms
socket.io.js:3524 engine.io-client:socket creating transport "xhr-polling" +0ms
socket.io.js:1284 socket.io-client:manager connect attempt will timeout after 20000 +4ms
socket.io.js:1284 socket.io-client:manager readyState opening +1ms
socket.io.js:1284 socket.io-client:manager connect_error +3ms
socket.io.js:1284 socket.io-client:manager will wait 1000ms before reconnect attempt +2ms
socket.io.js:1284 socket.io-client:manager attempting reconnect +1s
socket.io.js:1284 socket.io-client:manager readyState closed +0ms
socket.io.js:1284 socket.io-client:manager opening http://localhost:8190/ +1ms
socket.io.js:1284 socket.io-client:manager connect attempt will timeout after 20000 +0ms

这段日志不断重复，同时稳定地增加超时时间。

Answer 1

我发现这是因为Socket.IO版本1.0+实际上不允许在[websocket and polling]之外设置传输。将轮询设置为您的传输默认为polling-xhr，除非您在选项中将属性forceJSONP和/或jsonp设置为true。

换句话说，代码应该是：

var options = {"force new connection":true,
               "reconnect":false,
               "connect timeout":10000,
               "flash policy port":843,
               "auto connect":true,
               "path":"/sample/socket.io",
               "transports":["polling"]}

this.namespace = io.connect( 'http://localhost:8190/', options);

另请注意，'auto connect'现在是autoConnect，'force new connection'现在是forceNew，'connect timeout'现在是timeout和'reconnect'现在是'reconnection'。

var options = {forceNew :true,
               reconnection :false,
               timeout":10000,
               "flash policy port":843,
               autoConnect:true,
               "path":"/sample/socket.io",
               "transports":["polling"]}

通过xhr-polling和jsonp-polling超时连接

1 个答案: