通过 socket.id 向客户端发送消息

Question

当用户的套接字 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 sn-p

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

解决方案：感谢@alessioalex 我不得不从登录页面中删除对 socket.io 的引用，并将以下内容添加到 io.sockets.on('connection')

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，您应该确保他们只有在经过身份验证后才能连接。如果你使用 Express，那么下面这篇文章对你有很大帮助：http://www.danielbaulig.de/socket-ioexpress/

另外你应该避免像这样发送消息，因为这是 Socket.IO 内部的一部分并且可能会改变：

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

相反（如果您想向特定客户端发送消息）最好保留一个对象，例如与连接的客户端（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) 可能有效（实际上并没有测试），但它也可以随时更改，因为它是 Socket.IO 内部的一部分，所以我上面的解决方案更“安全”。

您可能希望在客户端代码中更改的另一件事是 var socket = io.connect(''); 和 var socket = io.connect('http://localhost');，正如我们在此处的 Socket.IO 官方示例中看到的那样：http://socket.io/#how-to-use

Answer 2

我可以看到这篇文章引起了很多兴趣......所以我将发布我用来实现这个的代码：

注意事项

我使用 Redis 作为会话存储。会话最初是在登录页面期间通过包含用户详细信息的 HTTP 请求设置的，如果这些详细信息有效（根据 MongoDB 文档检查）...然后创建会话。

服务器端代码创建和删除会话/套接字

//Auth the user
io.set('authorization', function (data, accept) {
  // check if there's a cookie header
  if (data.headers.cookie) {
    data.cookie = parseCookie(data.headers.cookie);
    data.sessionID = data.cookie['express.sid'];

    //Save the session store to the data object
    data.sessionStore = sessionStore;

    sessionStore.get(data.sessionID, function(err, session){
      if(err) throw err;

      if(!session)
      {
        console.error("Error whilst authorizing websocket handshake");
        accept('Error', false);
      }
      else
      {
        console.log("AUTH USERNAME: " + session.username);
        if(session.username){
          data.session = new Session(data, session);
          accept(null, true);
        }else {
          accept('Invalid User', false);
        }
      }
    })
  } else {
    console.error("No cookie was found whilst authorizing websocket handshake");
    return accept('No cookie transmitted.', false);
  }
});

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


  socket.on('disconnect', function()
  {
    delete browsing[hs.session.username]; //Remove the client from the browsing hash
    delete clients[socket.id];         // remove the client from the array
    delete validUsers[hs.session.username]; // remove connected user & socket.id
  })
....
}

服务器端选择性消息发送

此代码允许我向项目的团队成员发送消息。用户团队不会收到来自单独用户团队的消息..

for(var i = 0; i < project.team.length; i++)
{
  if(validUsers[project.team[i].username])
  {
    if(clients[validUsers[project.team[i].username]])
    {
      projects.update({"_id" : projectId},
        {"$pull" :
          {"stories" : {"_id" :  storyId}}
        }
      );                
      clients[validUsers[project.team[i].username]].emit('delete-story', storyId); 
    }
    else
    {
      console.error("Project team member not found");
    }
  }
}