Efficient way to broadcast from sockjs-node?

I'd like to broadcast messages to all clients connected to my sockjs-node server.

Right now I have the following code

var clients = {};
var echo = sockjs.createServer();
echo.on('connection', function(conn) {
    clients[conn.id] = conn;

    for(key in clients) {
        if(clients.hasOwnProperty(key)) {
            clients[key].write('test');
        }
    }

    conn.on('close', function() {
        delete clients[conn.id];
    });
});

Is there a more efficient way to do it ?

Maybe

var clients = [];
var echo = sockjs.createServer();
echo.on('connection', function(conn) {
    var index = clients.push(conn);

    var lenght = clients.length;
    while(length--) {
        if(clients[length] !== undefined) {
            clients[length].write('test');
        }
    }

    conn.on('close', function() {
        delete clients[index];
    });
});

Thanks