Read and writing to json file in php

read-write-json.php

<?php

$filename = 'filename.json';
//decode to json as associative array
$data = json_decode(file_get_contents($filename),true);

//init condition in case of empty file
if (!is_array($data)){
    $data = [];    
}

//operation/s on $data variables
array_push($data, "Hello world");

//encode to json
file_put_contents($filename, json_encode($blocklist));