通过socket.id向客户端发送消息

Question

当他们的socket id直接存储在io.sockets.on('connect')函数中时,我似乎只能向用户发出消息.我不知道为什么在他们登录后尝试存储他们的套接字ID时它不起作用.

工作:

  var clients = {};
  /** A new socket connection has been accepted */
  io.sockets.on('connection', function (socket)
  {
    //Used to access session id
    var hs = socket.handshake;            
        clients[socket.id] = socket; // add the client data to the hash   
        users['brownj2'] = socket.id; // connected user with its socket.id

    socket.on('user-login', function(user){
      if(!users[username]){
        //users[username] = socket.id; // connected user with its socket.id
      }
    })

    socket.on('page-load', function(pid)
    {
      if(users['brownj2'])
      {        
        clients[users['brownj2']].emit('hello');
      }
      else
      {
        console.log("NOT FOUND BROWNJ2");
      }
    }
  }

不工作:

  var clients = {};
  /** A new socket connection has been accepted */
  io.sockets.on('connection', function (socket)
  {
    //Used to access session id
    var hs = socket.handshake;            
        clients[socket.id] = socket; // add the client data to the hash            

    socket.on('user-login', function(user){          
      if(!users['brownj2']){
        users['brownj2'] = socket.id; // connected user with its socket.id
      }
    })

    socket.on('page-load', function(pid)
    {
      if(users['brownj2'])
      {        
        clients[users['brownj2']].emit('hello');
      }
      else
      {
        console.log("NOT FOUND BROWNJ2");
      }
    }
  }

JavaScript客户端代码段

var socket = io.connect('');
socket.on("hello", function(){
  alert("Hi Jack");
  console.log("WEBSOCKET RECIEVED");
})

解决方案:感谢@alessioalex 我必须从登录页面删除对socket.io的引用,并将以下内容添加到io.sockets.on('connection')中

var hs = socket.handshake;

sessionStore.get(hs.sessionID, function(err, session){
  console.log("SESSION: " + util.inspect(session));

  clients[socket.id] = socket; // add the client data to the hash
  validUsers[session.username] = socket.id; // connected user with its socket.id
})

Answer 1

您的代码存在一些问题,首先是您不应该通过Socket.IO对用户进行身份验证,您应该确保它们只有在经过身份验证后才能连接.如果您使用的是Express,那么下面的文章可以为您提供很多帮助:http://www.danielbaulig.de/socket-ioexpress/

你应该避免发送这样的消息,因为这是内部的Socket.IO的一部分,可能会改变:

io.sockets.socket(id).emit('hello');

相反(如果你想向特定客户端发送消息)最好保持一个对象,例如连接的客户端(并在断开连接后删除客户端):

// the clients hash stores the sockets
// the users hash stores the username of the connected user and its socket.id
io.sockets.on('connection', function (socket) {
  // get the handshake and the session object
  var hs = socket.handshake;
  users[hs.session.username] = socket.id; // connected user with its socket.id
  clients[socket.id] = socket; // add the client data to the hash
  ...
  socket.on('disconnect', function () {
    delete clients[socket.id]; // remove the client from the array
    delete users[hs.session.username]; // remove connected user & socket.id
  });
}

// we want at some point to send a message to user 'alex'
if (users['alex']) {
  // we get the socket.id for the user alex
  // and with that we can sent him a message using his socket (stored in clients)
  clients[users['alex']].emit("Hello Alex, how've you been");
}

当然,io.sockets.socket(id)可以工作(实际上没有测试),但它也可以随时更改,因为它是Socket.IO内部的一部分,所以我的解决方案更加"安全".

你可能想在客户端代码改变的另一件事情是var socket = io.connect('');有var socket = io.connect('http://localhost');,因为我们可以在Socket.IO的官方例子在这里看到:http://socket.io/#how-to-use