/wp-content/plugins/w3-total-cache/lib/W3/Cdn/Base.php

<?php



/**

 * W3 CDN Base class

 */



if (!defined('W3TC_CDN_RESULT_HALT')) {

    define('W3TC_CDN_RESULT_HALT', -1);

}



if (!defined('W3TC_CDN_RESULT_ERROR')) {

    define('W3TC_CDN_RESULT_ERROR', 0);

}



if (!defined('W3TC_CDN_RESULT_OK')) {

    define('W3TC_CDN_RESULT_OK', 1);

}



/**

 * Class W3_Cdn_Base

 */

class W3_Cdn_Base

{

    /**

     * CDN Configuration

     *

     * @var array

     */

    var $_config = array();

    

    /**

     * Cache config

     * @var array

     */

    var $cache_config = array();

    

    /**

     * PHP5 Constructor

     *

     * @param array $config

     */

    function __construct($config)

    {

        $this->_config = $config;

    }

    

    /**

     * PHP4 Constructor

     *

     * @param array $config

     */

    function W3_Cdn_Base($config)

    {

        $this->__construct($config);

    }

    

    /**

     * Upload files to CDN

     *

     * @param array $files

     * @param array $results

     * @param boolean $force_rewrite

     * @return boolean

     */

    function upload($files, &$results, $force_rewrite = false)

    {

        $results = $this->get_results($files, W3TC_CDN_RESULT_HALT, 'Not implemented.');

        

        return false;

    }

    

    /**

     * Delete files from CDN

     *

     * @param array $files

     * @param array $results

     * @return boolean

     */

    function delete($files, &$results)

    {

        $results = $this->get_results($files, W3TC_CDN_RESULT_HALT, 'Not implemented.');

        

        return false;

    }

    

    /**

     * Purges URLs from CDN

     * 

     * @param array $files

     * @param array $results

     * @return boolean

     */

    function purge($files, &$results)

    {

        return $this->upload($files, $results, true);

    }

    

    /**

     * Test CDN server

     *

     * @param string $error

     * @return boolean

     */

    function test(&$error)

    {

        if (!$this->_test_domains($error)) {

            return false;

        }

        

        return true;

    }

    

    /**

     * Create bucket / container for some CDN engines

     * 

     * @param string $container_id

     * @param string $error

     * @return boolean

     */

    function create_container(&$container_id, &$error)

    {

        $error = 'Not implemented.';

        

        return false;

    }

    

    /**

     * Returns first domain

     * 

     * @return string

     */

    function get_domain()

    {

        $domains = $this->get_domains();

        

        if (count($domains)) {

            return current($domains);

        }

        

        return false;

    }

    

    /**

     * Returns array of CDN domains

     *

     * @return array

     */

    function get_domains()

    {

        return array();

    }

    

    /**

     * Returns via string

     *

     * @return string

     */

    function get_via()

    {

        $domain = $this->get_domain();

        

        if ($domain) {

            return $domain;

        }

        

        return 'N/A';

    }

    

    /**

     * Formats object URL

     *

     * @param string $path

     * @return string

     */

    function format_url($path)

    {

        $domains = $this->get_domains();

        $count = count($domains);

        

        if ($count) {

            switch (true) {

                /**

                 * Reserved CSS

                 */

                case (isset($domains[0]) && $this->_is_css($path)):

                    $host = $domains[0];

                    break;

                

                /**

                 * Reserved JS in head

                 */

                case (isset($domains[1]) && $this->_is_js($path)):

                    $host = $domains[1];

                    break;

                

                /**

                 * Reserved JS after body

                 */

                case (isset($domains[2]) && $this->_is_js_body($path)):

                    $host = $domains[2];

                    break;

                

                /**

                 * Reserved JS before /body

                 */

                case (isset($domains[3]) && $this->_is_js_footer($path)):

                    $host = $domains[3];

                    break;

                

                default:

                    if ($count > 4) {

                        $host = $this->_get_host(array_slice($domains, 4), $path);

                    } else {

                        $host = $this->_get_host($domains, $path);

                    }

            }

            

            $url = sprintf('%s://%s/%s', (w3_is_https() ? 'https' : 'http'), $host, $path);

            

            return $url;

        }

        

        return false;

    }

    

    /**

     * Returns results

     *

     * @param array $files

     * @param integer $result

     * @param string $error

     * @return array

     */

    function get_results($files, $result = W3TC_CDN_RESULT_OK, $error = 'OK')

    {

        $results = array();

        

        foreach ($files as $local_path => $remote_path) {

            $results[] = $this->get_result($local_path, $remote_path, $result, $error);

        }

        

        return $results;

    }

    

    /**

     * Returns file process result

     *

     * @param string $local_path

     * @param string $remote_path

     * @param integer $result

     * @param string $error

     * @return array

     */

    function get_result($local_path, $remote_path, $result = W3TC_CDN_RESULT_OK, $error = 'OK')

    {

        return array(

            'local_path' => $local_path, 

            'remote_path' => $remote_path, 

            'result' => $result, 

            'error' => $error

        );

    }

    

    /**

     * Returns headers for file

     * 

     * @param string $file

     * @return array

     */

    function get_headers($file)

    {

        $mime_type = w3_get_mime_type($file);

        $last_modified = time();

        

        $headers = array(

            'Content-Type' => $mime_type, 

            'Last-Modified' => w3_http_date($last_modified)

        );

        

        if (isset($this->cache_config[$mime_type])) {

            if ($this->cache_config[$mime_type]['etag']) {

                $headers['Etag'] = @md5_file($file);

            }

            

            if ($this->cache_config[$mime_type]['w3tc']) {

                $headers['X-Powered-By'] = W3TC_POWERED_BY;

            }

            

            if ($this->cache_config[$mime_type]['lifetime']) {

                $headers['Expires'] = w3_http_date($last_modified + $this->cache_config[$mime_type]['lifetime']);

            }

            

            switch ($this->cache_config[$mime_type]['cache_control']) {

                case 'cache':

                    $headers = array_merge($headers, array(

                        'Pragma' => 'public', 

                        'Cache-Control' => 'public'

                    ));

                    break;

                

                case 'cache_validation':

                    $headers = array_merge($headers, array(

                        'Pragma' => 'public', 

                        'Cache-Control' => 'public, must-revalidate, proxy-revalidate'

                    ));

                    break;

                

                case 'cache_noproxy':

                    $headers = array_merge($headers, array(

                        'Pragma' => 'public', 

                        'Cache-Control' => 'public, must-revalidate'

                    ));

                    break;

                

                case 'cache_maxage':

                    $headers = array_merge($headers, array(

                        'Pragma' => 'public', 

                        'Cache-Control' => 'max-age=' . $this->cache_config[$mime_type]['lifetime'] . ', public, must-revalidate, proxy-revalidate'

                    ));

                    break;

                

                case 'no_cache':

                    $headers = array_merge($headers, array(

                        'Pragma' => 'no-cache', 

                        'Cache-Control' => 'max-age=0, private, no-store, no-cache, must-revalidate'

                    ));

                    break;

            }

        }

        

        return $headers;

    }

    

    /**

     * Use gzip compression only for text-based files

     * 

     * @param string $file

     * @return boolean

     */

    function may_gzip($file)

    {

        /**

         * Remove query string

         */

        $file = preg_replace('~\?.*$~', '', $file);

        

        /**

         * Check by file extension

         */

        if (preg_match('~\.(ico|js|css|xml|xsd|xsl|svg|htm|html|txt)$~i', $file)) {

            return true;

        }

        

        return false;

    }

    

    /**

     * Test domains

     * 

     * @param string $error

     * @return boolean

     */

    function _test_domains(&$error)

    {

        $domains = $this->get_domains();

        

        if (!count($domains)) {

            $error = 'Empty domains / CNAMEs list.';

            

            return false;

        

        }

        

        foreach ($domains as $domain) {

            if ($domain && gethostbyname($domain) === $domain) {

                $error = sprintf('Unable to resolve domain: %s.', $domain);

                

                return false;

            }

        }

        

        return true;

    }

    

    /**

     * Check if css file

     * 

     * @param string $path

     * @return boolean

     */

    function _is_css($path)

    {

        return preg_match('~[a-z0-9\-_]+\.include\.[0-9]+\.css$~', $path);

    }

    

    /**

     * Check if JS file in heeader

     * 

     * @param string $path

     * @return boolean

     */

    function _is_js($path)

    {

        return preg_match('~[a-z0-9\-_]+\.include(-nb)?\.[0-9]+\.js$~', $path);

    }

    

    /**

     * Check if JS file after body

     * 

     * @param string $path

     * @return boolean

     */

    function _is_js_body($path)

    {

        return preg_match('~[a-z0-9\-_]+\.include-body(-nb)?\.[0-9]+\.js$~', $path);

    }

    

    /**

     * Check if JS file before /body

     * 

     * @param string $path

     * @return boolean

     */

    function _is_js_footer($path)

    {

        return preg_match('~[a-z0-9\-_]+\.include-footer(-nb)?\.[0-9]+\.js$~', $path);

    }

    

    /**

     * Returns host for path

     * 

     * @param array $domains

     * @param string $path

     * @return string

     */

    function _get_host($domains, $path)

    {

        $count = count($domains);

        

        if ($count) {

            /**

             * Use for equal URLs same host to allow caching by browser

             */

            $hash = $this->_get_hash($path);

            $host = $domains[$hash % $count];

            

            return $host;

        }

        

        return false;

    }

    

    /**

     * Returns integer hash for key

     * 

     * @param string $key

     * @return integer

     */

    function _get_hash($key)

    {

        $hash = abs(crc32($key));

        

        return $hash;

    }

}