Encode data in php and uncompress in Javascript (ajax)

In order to reduce the size of my json file, I wanted to zip it. Hence, I am trying to compress json data file sent from php server :

header('Content-Encoding: gzip'); 
$output = gzencode(json_encode($data));     
echo $output;

And then, uncompress it in javascript (ajax methodd) :

$.ajax({
    url: url,
    type: "GET",
    headers : {'Accept-Encoding': 'gzip '},
    async: true,
    success: function (data) {
        console.log("sucess !!");
        console.log(data);
        ... 
    )};

I also modified apache server in order to uncompress it automagically :

LoadModule deflate_module modules/mod_deflate.so

And :

 <IfModule mod_headers.c>
  <FilesMatch ".(js|css|xml|gz|txt|json)$">
      Header append Vary: Accept-Encoding
  </FilesMatch>

However, I couldnt get the data properly (it stills compress).

Could you please let me know what I am doing wrong ?

Thank you

#javascript #php #apache