socket.io/node.js检测服务器是否已关闭

Is there something that I can do on the client side to detect that the socket.io websocket is not available? Something along the lines of:

我能在客户端做些什么来检测socket.io websocket是不可用的吗？有点像：

server starts as per usual
服务器按照惯例启动
clients connect
客户连接
messages are sent back and forth between server and client(s)
消息在服务器和客户端之间来回发送
server shuts down (no longer available)
服务器关闭（不再可用）
warn the connected clients that the server is not available
警告连接的客户端服务器不可用

I tried to add the 'error' and 'connect_failed' options on the client side but without any luck, those didn't trigger at all. Any ideas from anyone how I can achieve this?

我试图在客户端添加'error'和'connect_failed'选项，但没有任何运气，那些根本没有触发。任何人的想法我怎么能做到这一点？

4 个解决方案

#1

The disconnect event is what you want to listen on.

断开连接事件是您想要听的内容。

var socket = io.connect();

socket.on('connect', function () {
  alert('Socket is connected.');
});

socket.on('disconnect', function () {
  alert('Socket is disconnected.');
});

#2

If you want to be able to detect that the client was not able to connect to the server, then try using connect_error. This works for me with socket.io-1.3.5.js. I found this in https://*.com/a/28893421/2262092.

如果您希望能够检测到客户端无法连接到服务器，请尝试使用connect_error。这适用于socket.io-1.3.5.js。我在https://*.com/a/28893421/2262092中找到了这个。

Here's my code snippet:

这是我的代码片段：

var socket = io.connect('http://<ip>:<port>', {
    reconnection: false
});
socket.on('connect_error', function() {
    console.log('Failed to connect to server');
});

#3

hit this bug during my development and noticed my event calls were doubling up every time i reset the server, as my sockets reconnected. Turns out the solution that worked for me, which is not duping connections is this

在我开发过程中遇到这个bug，并注意到每次重置服务器时我的事件调用都会加倍，因为我的套接字重新连接。结果证明对我有用的解决方案，这不是重复连接

var socket = io.connect();

var socket = io.connect（）;

socket.on('connect', function () {

socket.on（'connect'，function（）{

console.log('User connected!');

console.log（'用户连接！'）;

});

}）;

socket.on('message', function(message) {

socket.on（'message'，function（message）{

console.log(message);

的console.log（消息）;

});

}）;

( Found this at https://github.com/socketio/socket.io/issues/430 by KasperTidemann )

（在KasperTidemann的https://github.com/socketio/socket.io/issues/430上找到）

Turns out, it was becuase I put the 'message' listener inside the 'connect' function. Seating it outside of the listener, solves this problem.

事实证明，这是因为我把'message'监听器放在'connect'函数中。将它放在听众之外，解决了这个问题。

Cheers to Kasper Tidemann, whereever you are.

欢迎来到Kasper Tidemann，无论你是谁。

Moving on!!

继续！！

#4

connect_error didn't work for me (using Apache ProxyPass and returns a 503).

connect_error对我不起作用（使用Apache ProxyPass并返回503）。

If you need to detect an initial failed connection, you can do this.

如果需要检测初始连接失败，可以执行此操作。

var socket;
try {
    socket = io();
}
catch(e) {
    window.location = "nodeServerDown.php";
}

Redirects the user to a custom error page when the server is down.

服务器关闭时，将用户重定向到自定义错误页面。

If you need to handle a disconnect after you've connected once.

如果您需要在连接一次后处理断开连接。

You do this:

你做这个：

socket.on('disconnect', function() {
    //whatever your disconnect logic is
});

#1