如何在symfony 3中使用twitter / tyepahead.js和blodhound实现自动完成功能

I have an ajax route which respond a json array with sites which gets it from a txt file. In my twig template Im using typeahead function to do an ajax call like:

var sites= new Bloodhound({
  datumTokenizer: Bloodhound.tokenizers.whitespace,
  queryTokenizer: Bloodhound.tokenizers.whitespace,

  remote: '{{'ajax_fun'}}'
});


$('#bloodhound .typeahead').typeahead({
  name: 'sites',
  source: sites
});

The filtering on input field does not work even thought i get the array with the sites.

In case someone want to know how to populate states with json array getting from remote path this was my solution:

var states = [];
var statesBloodhound = new Bloodhound({
  datumTokenizer: Bloodhound.tokenizers.whitespace,
  queryTokenizer: Bloodhound.tokenizers.whitespace,
  // `states` is an array of state names defined in "The Basics"
  local: states
});

//populate the statesBloodhound 
$.getJSON('path', {
}).done(function(data){
   statesBloodhound.add(data); 
})

$('#bloodhound .typeahead').typeahead({
  name: 'statesBloodhound ',
  source: statesBloodhound 
});