Forwarding communication

[peteruithoven]

I'd like to forward websocket communication (custom events, messages etc). I have to forward communication between clients because they can't reach each other directly (because they are usually behind routers etc).
Is there any way to handle any event, so I don't have to specify all the event names on my server?

I would really like to do is the following:

var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);

http.listen(3000);

var subject = null;

var nsp = io.of("/");
nsp.on('connection', function(socket){
  if(socket.handshake.query.isSubject) {
    subject = socket;
    // forward all events from subject to other clients in namespace
    subject.on("anything",function(data) {
      subject.broadcast.emit(data.type,data.payload);
    });
  } else {
    // forward all events from clients to subject
    socket.on("anything",function(data) {
      subject.emit(data.type,data.payload);
    }); 
  }
});

Looking through the code I found the onevent handler, and inspired by #1185 I figured out the following solution. My question is, is there a better solution?
(If there isn't I hope the solution is useful more people)

var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);

http.listen(3000);

var subject = null;

var nsp = io.of("/");
nsp.on('connection', function(socket){
  if(socket.handshake.query.isSubject) {
    subject = socket;
  }

  var oneventHandler = socket.onevent;
  socket.onevent = function() {
    oneventHandler.apply(this,arguments);
    var packet = arguments[0];
    var eventType = packet.data[0];
    var eventData = packet.data[1];
    var eventCallback = packet.data[2];
    if(socket === subject) {
      // forward all events from subject to other clients in namespace
      subject.broadcast.emit(eventType,eventData);
    } else {
      // forward all events from clients to subject
      subject.emit(eventType,eventData);
    }
  };
});

This handles all events, to go even more generic you could override onpacket.

[peteruithoven]

A colleague figured out a slightly more elegant way. This method creates a actual 'any' event and allows you to work with regular event listeners.

var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);

http.listen(3000);

var subject = null;

var nsp = io.of("/");
nsp.on('connection', function(socket){
  if(socket.handshake.query.isSubject) {
    subject = socket;
  }
  createAnyEvents(socket);

  socket.on('any', function (eventType,data,callback) {
    if(socket === subject) {
      // forward all events from subject to other clients in namespace
      subject.broadcast.emit(eventType,data);
    } else {
      // forward all events from clients to subject
      subject.emit(eventType,data,callback);
    }
  });
});
function createAnyEvents(socket) {
  var originalOnEvent = socket.onevent;
  socket.onevent = function() {
    // emit regular event
    originalOnEvent.apply(socket, arguments);
    var data = arguments[0].data;
    /** Note: turn this event into a 'any' event
    * We add the event type as first argument, the regular arguments 
    * (data and callback) become the subsequent arguments
    */
    data.unshift('any');
    // emit 'any' event
    originalOnEvent.apply(socket, arguments);
  };
}

[peteruithoven]

The following package also seems interesting, but it's probably not compatible with socket.io 1.0. It tries to override onClientMessage in a Manager, but this Manager doesn't seem to exist anymore.
https://www.npmjs.org/package/socket.io-wildcard

[NathanGRomano]

There is also https://npmjs.org/package/socket.io-events which gives you more of an express style routing of events, it supports wild cards and regular expressions.