Instagram PHP API - Receive ratelimit header

ratelimit.php

<?php

/**
 * Instagram PHP API
 * 
 * @link https://github.com/cosenary/Instagram-PHP-API
 * @author Christian Metz
 * @since 8.11.2014
 */

// include header in your response
curl_setopt($ch, CURLOPT_HEADER, true);

// execute API request
$response = curl_exec($ch);

// split header from JSON data
// and assign each to a variable
list($headerContent, $jsonData) = explode("\r\n\r\n", $response, 2);

// convert header content into an array
$headers = processHeaders($headerContent);

// get the 'X-Ratelimit-Remaining' header value
$ratelimitRemaining = $headers['X-Ratelimit-Remaining'];

function processHeaders($headerContent) {
  $headers = array();

  // iterate over the header string line by line
  foreach (explode("\r\n", $headerContent) as $i => $line) {
    if ($i === 0) {
      // the first line contains the HTTP response code
      $headers['http_code'] = $line;
    } else {
      // split headers into key (name) and value
      list($key, $value) = explode(': ', $line);
      $headers[$key] = $value;
    }
  }

  return $headers;
}