// initialize our modules
var io               = require("socket.io")(server),
    sessionStore     = require('awesomeSessionStore'), // find a working session store (have a look at the readme)
    passportSocketIo = require("passport.socketio");

// With Socket.io < 1.0
io.set('authorization', passportSocketIo.authorize({
  cookieParser: express.cookieParser,
  key:         'express.sid',       // the name of the cookie where express/connect stores its session_id
  secret:      'session_secret',    // the session_secret to parse the cookie
  store:       sessionStore,        // we NEED to use a sessionstore. no memorystore please
  success:     onAuthorizeSuccess,  // *optional* callback on success - read more below
  fail:        onAuthorizeFail,     // *optional* callback on fail/error - read more below
}));

//With Socket.io >= 1.0
io.use(passportSocketIo.authorize({
  cookieParser: cookieParser,       // the same middleware you registrer in express
  key:          'express.sid',       // the name of the cookie where express/connect stores its session_id
  secret:       'session_secret',    // the session_secret to parse the cookie
  store:        sessionStore,        // we NEED to use a sessionstore. no memorystore please
  success:      onAuthorizeSuccess,  // *optional* callback on success - read more below
  fail:         onAuthorizeFail,     // *optional* callback on fail/error - read more below
}));

function onAuthorizeSuccess(data, accept){
  console.log('successful connection to socket.io');

  // The accept-callback still allows us to decide whether to
  // accept the connection or not.
  accept(null, true);

  // OR

  // If you use [email protected] the callback looks different
  accept();
}

function onAuthorizeFail(data, message, error, accept){
  if(error)
    throw new Error(message);
  console.log('failed connection to socket.io:', message);

  // We use this callback to log all of our failed connections.
  accept(null, false);

  // OR

  // If you use [email protected] the callback looks different
  // If you don't want to accept the connection
  if(error)
    accept(new Error(message));
  // this error will be sent to the user as a special error-package
  // see: http://socket.io/docs/client-api/#socket > error-object
}

//in your app.js
var sessionStore = new redisStore();

app.use(session({
  key: 'express.sid',
  store: sessionStore,
  secret: 'keyboard cat'
}));

//in your passport.socketio setup
//With Socket.io >= 1.0 (you will have the same setup for Socket.io <1)
io.use(passportSocketIo.authorize({
  cookieParser: require('cookie-parser'), //optional your cookie-parser middleware function. Defaults to require('cookie-parser')
  key:          'express.sid',       //make sure is the same as in your session settings in app.js
  secret:       'keyboard cat',      //make sure is the same as in your session settings in app.js
  store:        sessionStore,        //you need to use the same sessionStore you defined in the app.use(session({... in app.js
  success:      onAuthorizeSuccess,  // *optional* callback on success
  fail:         onAuthorizeFail,     // *optional* callback on fail/error
}));

// accept connection
accept(null, true);

// reject connection (for whatever reason)
accept(null, false);

// accept connection
accept();

// reject connection (for whatever reason)
accept(new Error('optional reason'));

/* ... */
function onAuthorizeFail(data, message, error, accept){
  // error indicates whether the fail is due to an error or just a unauthorized client
  if(error){
    throw new Error(message);
  } else {
    console.log(message);
    // the same accept-method as above in the success-callback
    accept(null, false);
  }
}

// or
// This function accepts every client unless there's an error
function onAuthorizeFail(data, message, error, accept){
  console.log(message);
  accept(null, !error);
}

function onAuthorizeFail(data, message, error, accept){
  // error indicates whether the fail is due to an error or just a unauthorized client
  if(error)  throw new Error(message);
  // send the (not-fatal) error-message to the client and deny the connection
  return accept(new Error(message));
}

// or
// This function accepts every client unless there's an critical error
function onAuthorizeFail(data, message, error, accept){
  if(error)  throw new Error(message);
  return accept();
}

passportSocketIo.filterSocketsByUser(io, function(user){
  return user.gender === 'female';
}).forEach(function(socket){
  socket.emit('messsage', 'hello, woman!');
});

// Note: ther's no readCookie-function built in.
// Get your own in the internetz
socket = io.connect('//' + window.location.host, {
  query: 'session_id=' + readCookie('your.sid-key')
});