Basic scanning with Noble

gistfile1.js

var noble = require('noble');

//replace localhost with your server's IP;
var socket = require('socket.io-client')('http://localhost/scanner');

//replace with your hardware address
var addressToTrack = '7c669d9b2dda'; 

socket.on('connect', function(){  
  console.log('connected to server');
});

noble.on('discover', function(peripheral){
  if(peripheral.uuid == addressToTrack){
    socket.emit('deviceData', {mac: peripheral.uuid, rssi:peripheral.rssi});    
  }
});

noble.startScanning([], true) //allows dubplicates while scanning