PHP pull Instagram feed and display with cache

instagram-pull.php

<?php 
      $cache_file = getcwd() . '/media/latest_gram.json';
      $cache_life = '120'; //caching time, in seconds
  
    if ( !file_exists($cache_file) or ( time() - filemtime($cache_file) >= $cache_life ) ) {
file_put_contents( $cache_file, file_get_contents('https://api.instagram.com/v1/users/self/media/recent/?access_token=xxx&count=1') );
      } 
      $json = file_get_contents( $cache_file );
      $ig_array = json_decode( $json );
    ?>
    
<a target="_blank" href="<?php echo $ig_array->data[0]->link ?>"><img src="<?php echo $ig_array->data[0]->images->low_resolution->url; ?>" /></a>