WebSocket：如何在它失效后自动重新连接

javascript websocket

2022-08-30 03:08:57

var ws = new WebSocket('ws://localhost:8080');
ws.onopen = function () {
  ws.send(JSON.stringify({
      .... some message the I must send when I connect ....
  }));

};

ws.onmessage = function (e) {
  console.log('Got a message')
  console.log(e.data);
};

ws.onclose = function(e) {  
  console.log('socket closed try again'); 

}

ws.onerror = function(err) {
  console.error(err)
};

当我第一次连接到套接字时，我必须首先向服务器发送一条消息，以验证自己的身份并订阅通道。

我遇到的问题是，有时套接字服务器不可靠，这会触发对象的和事件。onerroronclose'ws'

问：什么是好的设计模式，每当套接字关闭或遇到错误时，请等待 10 秒钟，然后重新连接到套接字服务器（并将初始消息重新发送到服务器）

答案 1

这是我最终得到的。它适用于我的目的。

function connect() {
  var ws = new WebSocket('ws://localhost:8080');
  ws.onopen = function() {
    // subscribe to some channels
    ws.send(JSON.stringify({
        //.... some message the I must send when I connect ....
    }));
  };

  ws.onmessage = function(e) {
    console.log('Message:', e.data);
  };

  ws.onclose = function(e) {
    console.log('Socket is closed. Reconnect will be attempted in 1 second.', e.reason);
    setTimeout(function() {
      connect();
    }, 1000);
  };

  ws.onerror = function(err) {
    console.error('Socket encountered error: ', err.message, 'Closing socket');
    ws.close();
  };
}

connect();

答案 2

这对我有用，因为客户端连接可能会丢失。setInterval

ngOnInit(): void {
    if (window.location.protocol.includes('https')) {
        this.protocol = 'wss';
    }

    this.listenChanges();
}


listenChanges(): void {
    this.socket = new WebSocket(`${this.protocol}://${window.location.host}/v1.0/your/url`);

    this.socket.onmessage = (event): void => {
        // your subscription stuff
        this.store.dispatch(someAction);
    };

    this.socket.onerror = (): void => {
        this.socket.close();
    };


    this.socket.onopen = (): void => {
        clearInterval(this.timerId);

        this.socket.onclose = (): void => {
            this.timerId = setInterval(() => {
                this.listenChanges();
            }, 10000);
        };
    };
}

不要忘记在插槽打开后呼叫。clearInterval