客户端断开连接后的服务器清理

Question

有没有办法通过刷新或导航离开页面来检测客户端何时断开与流星服务器的连接,以便服务器可以尝试进行一些清理？

Answer 1

一种技术是实现每个客户经常调用的"keepalive"方法.这假设您已经拥有user_id每个客户的账户Session.

// server code: heartbeat method
Meteor.methods({
  keepalive: function (user_id) {
    if (!Connections.findOne(user_id))
      Connections.insert({user_id: user_id});

    Connections.update(user_id, {$set: {last_seen: (new Date()).getTime()}});
  }
});

// server code: clean up dead clients after 60 seconds
Meteor.setInterval(function () {
  var now = (new Date()).getTime();
  Connections.find({last_seen: {$lt: (now - 60 * 1000)}}).forEach(function (user) {
    // do something here for each idle user
  });
});

// client code: ping heartbeat every 5 seconds
Meteor.setInterval(function () {
  Meteor.call('keepalive', Session.get('user_id'));
}, 5000);

Answer 2

我认为更好的方法是在发布函数中捕获套接字关闭事件.

Meteor.publish("your_collection", function() {
    this.session.socket.on("close", function() { /*do your thing*/});
}

更新:

较新版本的meteor使用_session,如下所示:

this._session.socket.on("close", function() { /*do your thing*/});