通过 socket.id 向客户端发送消息
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【中文标题】通过 socket.id 向客户端发送消息【英文标题】:Sending a message to a client via its socket.id 【发布时间】:2012-01-18 01:28:26 【问题描述】: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
)
【问题讨论】:
【参考方案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
【讨论】:
谢谢,但是当我尝试使用 socket.on('login', .....) users[u] = socket.id 时它不起作用。我似乎只能在 io.sockets.on('connection') 中直接添加用户 你确定吗?由于 socket 是一个在“上方”定义的变量,因此它也应该在该函数中可见,就像我在示例中显示的断开连接一样。 我已经修改了这个问题,以向您展示一个有效和无效的示例。我不明白为什么它不允许我在上面的“非工作”示例中发送消息。 你能在里面有console.log(socket.id)和console.log(socket)吗? 那么..问题出在哪里?您说 users[u] = socket.id 不起作用,但是如果您 console.log(socket.id) 向您显示他的 id?您在其他地方还有其他问题吗..?【参考方案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");
【讨论】:
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