title: (Node js) How to send notification to specific user?
body: <p>i have code for server
  server.js</p>
  
  <pre><code>var socket  = require( 'socket.io' );
  var express = require('express');
  var app     = express();
  var server  = require('http').createServer(app);
  var io      = socket.listen( server );
  var port    = process.env.PORT || 3000;
  var nik = {};
  
  server.listen(port, function () {
    console.log('Server listening at port %d', port);
  });
  
  
  io.on('connection', function (socket) {
      socket.on( 'new_count_message', function( data ) {
          io.sockets.emit( 'new_count_message', {
              new_count_message: data.new_count_message
          });
      });
  
      socket.on( 'update_count_message', function( data ) {
          io.sockets.emit( 'update_count_message', {
              update_count_message: data.update_count_message
          });
      });
  
  });
  </code></pre>
  
  <p>and this is how i use that</p>
  
  <pre><code>$.ajax({
              type: "POST",
              url: "(some_url)",
              data: $("id_form").serialize(),
              dataType: "json",
              beforeSend:function(){
                  alert('bla..bla..');
              },
              success: function (result) {
                  if (result.status) {
                      var socket = io.connect('http://' + window.location.hostname + ':3000');
                      socket.emit('new_count_message', {
                          new_count_message: result.new_count_message
                      });
                  } else if (result.status == false) {
                      alert(error);
                      return false;
                  }
              },
              error: function(xhr, Status, error) {
                  alert(error);
              }
          });
  </code></pre>
  
  <p>that function is working perfectly, but it send to all. how to send notif to specific user? i have the ID user that i want to send the notif</p>
  
  <p>Thanks</p>