node-sensortag EventEmitter leak example

snippet.js

var SensorTag = require( "sensortag" );
var EventEmitter = require( "events" );

var tags = {};
var tagCount = 0;

SensorTag.CC2540.SCAN_DUPLICATES = true;
SensorTag.CC2650.SCAN_DUPLICATES = true;

function startDiscover()
{
  if( tagCount > 0 ) return;

  console.log( "Starting discovery listener..." );
  SensorTag.discoverAll( onDiscover );

  setTimeout( connectToDiscovered , 5000 );
}

function connectToDiscovered()
{
  if( tagCount > 0 )
  {
    SensorTag.stopDiscoverAll( onDiscover );
    for( var id in tags )
    {
      tags[ id ].connect();
    }
  }
  else
  {
    console.log( "...nothing found...yet" );
    setTimeout( connectToDiscovered , 5000 );
  }
}

function onDiscover( tag )
{
  if( tags.hasOwnProperty( tag.uuid ) )
  {
    tags[ tag.uuid ].discoveredCount++;
    return;
  }

  console.log( "Discovered: " + tag.uuid );

  tags[ tag.uuid ] = new Tag( tag );
  tagCount++;
}

function Tag( tag )
{
  this.tag = tag;
  this.humidityInterval = null;
  this.disconnected = false;

  this.discoveredCount = 1;
}

Tag.prototype.log = function( msg ) {
  console.log( "[" + this.tag.uuid + "] " + msg );
};

Tag.prototype.connect = function() {

  this.log( "Discovered " + this.discoveredCount + " time(s)" );
  this.log( "Connecting..." );
  var self = this;

  this.tag.connectAndSetUp( function( error ) {

    if( error )
    {
      self.log( "Error connecting..." );
      return;
    }

    self.log( "Connected..." );

    self.tag.enableHumidity( function( error ) {
      if( error )
      {
        self.log( "Humidity error: " + error );
      }
    } );

    self.humidityInterval = setInterval( self.readHumidity.bind( self ) , 1000 );

    self.log( "Disconnect event count (tag): " + self.tag.listeners( "disconnect" ).length );
    self.log( "Disconnect event count (tag._peripheral): " + self.tag._peripheral.listeners( "disconnect" ).length );
    self.log( "Disconnect event count (tag._peripheral,direct): " + self.tag._peripheral._events.disconnect.length );

  } );

  this.tag.on( "disconnect" , function() {
    if( this.disconnected ) return;
    this.disconnected = true;
    self.destroy();
  } );
};

Tag.prototype.disconnect = function() {
  var self = this;

  this.tag.disconnect( function() {
    self.log( "Disconnected..." );
  } );
};

Tag.prototype.destroy = function() {
  this.log( "Destroyed..." );

  if( this.humidityInterval !== null ) clearInterval( this.humidityInterval );

  delete tags[ this.tag.uuid ];
  tagCount--;
  startDiscover();
};

Tag.prototype.readHumidity = function() {
  this.tag.readHumidity( this.humidityCallback.bind( this ) );
};

Tag.prototype.humidityCallback = function( error , temp , hum ) {
  if( error ) this.log( "Humidity error: " + error );
  else this.log( temp + " " + hum );
};

startDiscover();