monitor.io

monitor.io is a module for Node.js that runs as a telnet server, giving a remote client control of and information about sockets connected to an instance of socket.io.

This makes it possible to disconnect, emit, or broadcast data to sockets in a remote terminal without interrupting the Node.js process running socket.io. monitor.io also provides a real-time display of any data attached to a socket with the socket#monitor method.

Installation

$ npm install monitor.io

Usage

var socketio = require('socket.io')(server),
    monitorio = require('monitor.io');

socketio.use(monitorio({ port: 8000 }));
// monitor.io started on port 8000

Use telnet to connect to monitor.io and control a real-time list of sockets connected to socket.io.

$ telnet myapp.com 8000

Use hjkl to scroll verticall/horizontally through the list of sockets, e to emit data to a specific socket, and b to broadcast data to all sockets.

Monitoring

monitor.io attaches a method named monitor to every socket object. This method attaches data to a socket and tells monitor.io to render this data in the monitor.io terminal window.

Here is an example of how to attach the time that a socket connected to socket.io:

io.on('connection', function(socket) {
  socket.monitor('timeConnected', Date.now());  
});

socket#monitor must be called whenever monitored information changes, such as the score of a player in a real-time game, to force a rerender in the monitor.io window.

socket.on('newHighScore', function(msg) {
  var score = msg.score;
  socket.monitor('highScore', msg.score);
});

The monitor method also accepts an object, and will display every key-value pair in an object.

socket.on('newPlayer', function(msg) {
  var newPlayer = game.createPlayer();
  socket.monitor(newPlayer); 
  // every key-value pair in newPlayer will be shown
  // in the monitor.io terminal window.
});