PHP cURL wrapper

curl.php

<?php
/* cURL helper class
 * Author:  Johan P. <johan@asbra.net>
 * Created: 2011-02-19
 * Updated: 2011-07-27
 * Updated: 2011-09-10
 * Updated: 2011-10-04
 * Updated: 2012-07-21
 * Updated: 2013-01-15
 * Updated: 2013-02-04
 */

class cURL
{
  private $useragent; // user agent string
  private $handle;    // handle to the cURL object
  private $cookies;   // boolean value whether to use/store cookies or not
  private $redirs;    // boolean value whether to follow redirects or not
  private $xhr;        // boolean value whether to use XHR (XMLHttpRequest) or not

  public $cookiejar;  // filename of the cookie jar
  public $data;       // last data returned from a cURL transfer
  public $code;       // the last HTTP code returned
  public $url;        // URL of the page we are currently at
  public $info;       // information about the last cURL transfer

  private $proxy;     // proxy adress
  private $proxypwd;  // proxy password

  /* $redirs    Should we follow redirects or not
   * $cookies   Use cookies or not
   * $useragent The UserAgent string to send, try to keep this updated
   */
  function __construct($redirs = true, $cookies = true, $useragent = 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.17 (KHTML, like Gecko) Chrome/24.0.1312.57 Safari/537.17')
  {
    $this->useragent = $useragent;
    $this->handle    = null;
    $this->cookies   = $cookies;
    $this->redirs    = $redirs;
    $this->cookiejar = 'cookies.txt';
    $this->proxy     = '';
    $this->proxypwd  = '';
    $this->xhr       = false;
  }

  /* Public so we can set a proxy before making a request
   * when switching proxy, remember to clear cookies by cleanup()
   */
  public function set_proxy($proxy, $auth = '')
  {
    $this->proxy    = $proxy;
    $this->proxypwd = $auth;
  }

  /* Wrapper for curl_setopt
   */
  private function setopt($url, $referer)
  {
    // Set request URL
    curl_setopt($this->handle, CURLOPT_URL, $url);

    // Remove any current HTTP headers
    curl_setopt($this->handle, CURLOPT_HEADER, 0);

    // Follow redirects, or not
    if ($this->redirs)
    {
      curl_setopt($this->handle, CURLOPT_FOLLOWLOCATION, 1);
      curl_setopt($this->handle, CURLOPT_MAXREDIRS, 10);
    }
    else
    {
      curl_setopt($this->handle, CURLOPT_FOLLOWLOCATION, 0);
      curl_setopt($this->handle, CURLOPT_MAXREDIRS, 0);
    }

    // Return data from transfer
    curl_setopt($this->handle, CURLOPT_RETURNTRANSFER, 1);

    // Set UserAgent string
    curl_setopt($this->handle, CURLOPT_USERAGENT, $this->useragent);

    // If it's a HTTPS (SSL) URL, disable verification
    if (substr($url, 4, 1) == 's')
    {
      curl_setopt($this->handle, CURLOPT_SSL_VERIFYPEER, false);
      curl_setopt($this->handle, CURLOPT_SSL_VERIFYHOST, false);
    }

    // Set cookie jar
    if ($this->cookies)
    {
      curl_setopt($this->handle, CURLOPT_COOKIEJAR, $this->cookiejar);
      curl_setopt($this->handle, CURLOPT_COOKIEFILE, $this->cookiejar);
    }

    // If a proxy is set, use it
    if ($this->proxy != '')
    {
      curl_setopt($this->handle, CURLOPT_PROXY, $this->proxy);

      if ($this->proxypwd != '')
      {
        curl_setopt($this->handle, CURLOPT_PROXYUSERPWD, $this->proxypwd);
      }
    }

    // Set referrer if one is specified
    if ($referer != '')
    {
      curl_setopt($this->handle, CURLOPT_REFERER, $referer);
    }

    // XHR
    if ($this->xhr == true)
    {
      curl_setopt($this->handle, CURLOPT_HTTPHEADER, array("X-Requested-With: XMLHttpRequest"));
    }
  }

  /* Make a POST request
   */
  function post($url, $data, $referer = '', $xhr = false)
  {
    $this->handle = curl_init();

    $fields_string = '';
    if (is_array($data))
    {
      foreach ($data as $key => $value)
      {
        $fields_string .= $key.'='.$value.'&';
      }
      rtrim($fields_string, '&');
    }
    else
    {
      $fields_string = $data;
    }

    $this->xhr = $xhr;
    $this->setopt($url, $referer);

    curl_setopt($this->handle, CURLOPT_POST, 1);
    curl_setopt($this->handle, CURLOPT_POSTFIELDS, $fields_string);

    $this->data = curl_exec($this->handle);
    $this->code = curl_getinfo($this->handle, CURLINFO_HTTP_CODE);
    $this->info = curl_getinfo($this->handle);
    $this->url  = (isset($this->info['redirect_url']) && !empty($this->info['redirect_url']) ? $this->info['redirect_url'] : $this->info['url']);
    curl_close($this->handle);

    return $this->data;
  }

  /* Make a GET request
   */
  function get($url, $referer = '', $xhr = false)
  {
    $this->handle = curl_init();

    $this->xhr = $xhr;
    $this->setopt($url, $referer);

    $this->data = curl_exec($this->handle);
    $this->code = curl_getinfo($this->handle, CURLINFO_HTTP_CODE);
    $this->info = curl_getinfo($this->handle);
    $this->url  = (isset($this->info['redirect_url']) && !empty($this->info['redirect_url']) ? $this->info['redirect_url'] : $this->info['url']);
    curl_close($this->handle);

    return $this->data;
  }

  /* Removes stored cookies
   */
  public function cleanup()
  {
    if (file_exists($this->cookiejar))
    {
      unlink($this->cookiejar);
    }
  }

  /* Simple helper function to get data between two strings
   * $string  The string to search in
   * $str1    The start string to find
   * $str2    The end string to find
   * usage $curl->between($curl->data, '<h1>', '</h1>');
   * However if you are parsing HTML, it's better to use a DOM library.
   */
  function between($string, $str1, $str2)
  {
    $pos = strpos($string, $str1);
    if ($pos === false)
    {
      return '';
    }

    $end = strpos($string, $str2, $pos+strlen($str1));

    return substr($string, $pos+strlen($str1), ($end-$pos)-strlen($str1));
  }
}

?>