Subversion-Projekte lars-tiefland.php_share

<?php

/**

 * PEAR_REST

 *

 * PHP versions 4 and 5

 *

 * @category   pear

 * @package    PEAR

 * @author     Greg Beaver <cellog@php.net>

 * @copyright  1997-2009 The Authors

 * @license    http://opensource.org/licenses/bsd-license.php New BSD License

 * @version    CVS: $Id: REST.php 313023 2011-07-06 19:17:11Z dufuz $

 * @link       http://pear.php.net/package/PEAR

 * @since      File available since Release 1.4.0a1

 */

/**

 * For downloading xml files

 */

require_once 'PEAR.php';

require_once 'PEAR/XMLParser.php';

/**

 * Intelligently retrieve data, following hyperlinks if necessary, and re-directing

 * as well

 * @category   pear

 * @package    PEAR

 * @author     Greg Beaver <cellog@php.net>

 * @copyright  1997-2009 The Authors

 * @license    http://opensource.org/licenses/bsd-license.php New BSD License

 * @version    Release: 1.9.4

 * @link       http://pear.php.net/package/PEAR

 * @since      Class available since Release 1.4.0a1

 */

class PEAR_REST

{

    var $config;

    var $_options;

    function PEAR_REST(&$config, $options = array())

    {

        $this->config   = &$config;

        $this->_options = $options;

    }

    /**

     * Retrieve REST data, but always retrieve the local cache if it is available.

     *

     * This is useful for elements that should never change, such as information on a particular

     * release

     * @param string full URL to this resource

     * @param array|false contents of the accept-encoding header

     * @param boolean     if true, xml will be returned as a string, otherwise, xml will be

     *                    parsed using PEAR_XMLParser

     * @return string|array

     */

    function retrieveCacheFirst($url, $accept = false, $forcestring = false, $channel = false)

    {

        $cachefile = $this->config->get('cache_dir') . DIRECTORY_SEPARATOR .

            md5($url) . 'rest.cachefile';

        if (file_exists($cachefile)) {

            return unserialize(implode('', file($cachefile)));

        }

        return $this->retrieveData($url, $accept, $forcestring, $channel);

    }

    /**

     * Retrieve a remote REST resource

     * @param string full URL to this resource

     * @param array|false contents of the accept-encoding header

     * @param boolean     if true, xml will be returned as a string, otherwise, xml will be

     *                    parsed using PEAR_XMLParser

     * @return string|array

     */

    function retrieveData($url, $accept = false, $forcestring = false, $channel = false)

    {

        $cacheId = $this->getCacheId($url);

        if ($ret = $this->useLocalCache($url, $cacheId)) {

            return $ret;

        }

        $file = $trieddownload = false;

        if (!isset($this->_options['offline'])) {

            $trieddownload = true;

            $file = $this->downloadHttp($url, $cacheId ? $cacheId['lastChange'] : false, $accept, $channel);

        }

        if (PEAR::isError($file)) {

            if ($file->getCode() !== -9276) {

                return $file;

            }

            $trieddownload = false;

            $file = false; // use local copy if available on socket connect error

        }

        if (!$file) {

            $ret = $this->getCache($url);

            if (!PEAR::isError($ret) && $trieddownload) {

                // reset the age of the cache if the server says it was unmodified

                $result = $this->saveCache($url, $ret, null, true, $cacheId);

                if (PEAR::isError($result)) {

                    return PEAR::raiseError($result->getMessage());

                }

            }

            return $ret;

        }

        if (is_array($file)) {

            $headers      = $file[2];

            $lastmodified = $file[1];

            $content      = $file[0];

        } else {

            $headers      = array();

            $lastmodified = false;

            $content      = $file;

        }

        if ($forcestring) {

            $result = $this->saveCache($url, $content, $lastmodified, false, $cacheId);

            if (PEAR::isError($result)) {

                return PEAR::raiseError($result->getMessage());

            }

            return $content;

        }

        if (isset($headers['content-type'])) {

            switch ($headers['content-type']) {

                case 'text/xml' :

                case 'application/xml' :

                case 'text/plain' :

                    if ($headers['content-type'] === 'text/plain') {

                        $check = substr($content, 0, 5);

                        if ($check !== '<?xml') {

                            break;

                        }

                    }

                    $parser = new PEAR_XMLParser;

                    PEAR::pushErrorHandling(PEAR_ERROR_RETURN);

                    $err = $parser->parse($content);

                    PEAR::popErrorHandling();

                    if (PEAR::isError($err)) {

                        return PEAR::raiseError('Invalid xml downloaded from "' . $url . '": ' .

                            $err->getMessage());

                    }

                    $content = $parser->getData();

                case 'text/html' :

                default :

                    // use it as a string

            }

        } else {

            // assume XML

            $parser = new PEAR_XMLParser;

            $parser->parse($content);

            $content = $parser->getData();

        }

        $result = $this->saveCache($url, $content, $lastmodified, false, $cacheId);

        if (PEAR::isError($result)) {

            return PEAR::raiseError($result->getMessage());

        }

        return $content;

    }

    function useLocalCache($url, $cacheid = null)

    {

        if ($cacheid === null) {

            $cacheidfile = $this->config->get('cache_dir') . DIRECTORY_SEPARATOR .

                md5($url) . 'rest.cacheid';

            if (!file_exists($cacheidfile)) {

                return false;

            }

            $cacheid = unserialize(implode('', file($cacheidfile)));

        }

        $cachettl = $this->config->get('cache_ttl');

        // If cache is newer than $cachettl seconds, we use the cache!

        if (time() - $cacheid['age'] < $cachettl) {

            return $this->getCache($url);

        }

        return false;

    }

    function getCacheId($url)

    {

        $cacheidfile = $this->config->get('cache_dir') . DIRECTORY_SEPARATOR .

            md5($url) . 'rest.cacheid';

        if (!file_exists($cacheidfile)) {

            return false;

        }

        $ret = unserialize(implode('', file($cacheidfile)));

        return $ret;

    }

    function getCache($url)

    {

        $cachefile = $this->config->get('cache_dir') . DIRECTORY_SEPARATOR .

            md5($url) . 'rest.cachefile';

        if (!file_exists($cachefile)) {

            return PEAR::raiseError('No cached content available for "' . $url . '"');

        }

        return unserialize(implode('', file($cachefile)));

    }

    /**

     * @param string full URL to REST resource

     * @param string original contents of the REST resource

     * @param array  HTTP Last-Modified and ETag headers

     * @param bool   if true, then the cache id file should be regenerated to

     *               trigger a new time-to-live value

     */

    function saveCache($url, $contents, $lastmodified, $nochange = false, $cacheid = null)

    {

        $cache_dir   = $this->config->get('cache_dir');

        $d           = $cache_dir . DIRECTORY_SEPARATOR . md5($url);

        $cacheidfile = $d . 'rest.cacheid';

        $cachefile   = $d . 'rest.cachefile';

        if (!is_dir($cache_dir)) {

            if (System::mkdir(array('-p', $cache_dir)) === false) {

              return PEAR::raiseError("The value of config option cache_dir ($cache_dir) is not a directory and attempts to create the directory failed.");

            }

        }

        if ($cacheid === null && $nochange) {

            $cacheid = unserialize(implode('', file($cacheidfile)));

        }

        $idData = serialize(array(

            'age'        => time(),

            'lastChange' => ($nochange ? $cacheid['lastChange'] : $lastmodified),

        ));

        $result = $this->saveCacheFile($cacheidfile, $idData);

        if (PEAR::isError($result)) {

            return $result;

        } elseif ($nochange) {

            return true;

        }

        $result = $this->saveCacheFile($cachefile, serialize($contents));

        if (PEAR::isError($result)) {

            if (file_exists($cacheidfile)) {

              @unlink($cacheidfile);

            }

            return $result;

        }

        return true;

    }

    function saveCacheFile($file, $contents)

    {

        $len = strlen($contents);

        $cachefile_fp = @fopen($file, 'xb'); // x is the O_CREAT|O_EXCL mode

        if ($cachefile_fp !== false) { // create file

            if (fwrite($cachefile_fp, $contents, $len) < $len) {

                fclose($cachefile_fp);

                return PEAR::raiseError("Could not write $file.");

            }

        } else { // update file

            $cachefile_lstat = lstat($file);

            $cachefile_fp = @fopen($file, 'wb');

            if (!$cachefile_fp) {

                return PEAR::raiseError("Could not open $file for writing.");

            }

            $cachefile_fstat = fstat($cachefile_fp);

            if (

              $cachefile_lstat['mode'] == $cachefile_fstat['mode'] &&

              $cachefile_lstat['ino']  == $cachefile_fstat['ino'] &&

              $cachefile_lstat['dev']  == $cachefile_fstat['dev'] &&

              $cachefile_fstat['nlink'] === 1

            ) {

                if (fwrite($cachefile_fp, $contents, $len) < $len) {

                    fclose($cachefile_fp);

                    return PEAR::raiseError("Could not write $file.");

                }

            } else {

                fclose($cachefile_fp);

                $link = function_exists('readlink') ? readlink($file) : $file;

                return PEAR::raiseError('SECURITY ERROR: Will not write to ' . $file . ' as it is symlinked to ' . $link . ' - Possible symlink attack');

            }

        }

        fclose($cachefile_fp);

        return true;

    }

    /**

     * Efficiently Download a file through HTTP.  Returns downloaded file as a string in-memory

     * This is best used for small files

     *

     * If an HTTP proxy has been configured (http_proxy PEAR_Config

     * setting), the proxy will be used.

     *

     * @param string  $url       the URL to download

     * @param string  $save_dir  directory to save file in

     * @param false|string|array $lastmodified header values to check against for caching

     *                           use false to return the header values from this download

     * @param false|array $accept Accept headers to send

     * @return string|array  Returns the contents of the downloaded file or a PEAR

     *                       error on failure.  If the error is caused by

     *                       socket-related errors, the error object will

     *                       have the fsockopen error code available through

     *                       getCode().  If caching is requested, then return the header

     *                       values.

     *

     * @access public

     */

    function downloadHttp($url, $lastmodified = null, $accept = false, $channel = false)

    {

        static $redirect = 0;

        // always reset , so we are clean case of error

        $wasredirect = $redirect;

        $redirect = 0;

        $info = parse_url($url);

        if (!isset($info['scheme']) || !in_array($info['scheme'], array('http', 'https'))) {

            return PEAR::raiseError('Cannot download non-http URL "' . $url . '"');

        }

        if (!isset($info['host'])) {

            return PEAR::raiseError('Cannot download from non-URL "' . $url . '"');

        }

        $host   = isset($info['host']) ? $info['host'] : null;

        $port   = isset($info['port']) ? $info['port'] : null;

        $path   = isset($info['path']) ? $info['path'] : null;

        $schema = (isset($info['scheme']) && $info['scheme'] == 'https') ? 'https' : 'http';

        $proxy_host = $proxy_port = $proxy_user = $proxy_pass = '';

        if ($this->config->get('http_proxy')&&

              $proxy = parse_url($this->config->get('http_proxy'))

        ) {

            $proxy_host = isset($proxy['host']) ? $proxy['host'] : null;

            if ($schema === 'https') {

                $proxy_host = 'ssl://' . $proxy_host;

            }

            $proxy_port   = isset($proxy['port']) ? $proxy['port'] : 8080;

            $proxy_user   = isset($proxy['user']) ? urldecode($proxy['user']) : null;

            $proxy_pass   = isset($proxy['pass']) ? urldecode($proxy['pass']) : null;

            $proxy_schema = (isset($proxy['scheme']) && $proxy['scheme'] == 'https') ? 'https' : 'http';

        }

        if (empty($port)) {

            $port = (isset($info['scheme']) && $info['scheme'] == 'https')  ? 443 : 80;

        }

        if (isset($proxy['host'])) {

            $request = "GET $url HTTP/1.1\r\n";

        } else {

            $request = "GET $path HTTP/1.1\r\n";

        }

        $request .= "Host: $host\r\n";

        $ifmodifiedsince = '';

        if (is_array($lastmodified)) {

            if (isset($lastmodified['Last-Modified'])) {

                $ifmodifiedsince = 'If-Modified-Since: ' . $lastmodified['Last-Modified'] . "\r\n";

            }

            if (isset($lastmodified['ETag'])) {

                $ifmodifiedsince .= "If-None-Match: $lastmodified[ETag]\r\n";

            }

        } else {

            $ifmodifiedsince = ($lastmodified ? "If-Modified-Since: $lastmodified\r\n" : '');

        }

        $request .= $ifmodifiedsince .

            "User-Agent: PEAR/1.9.4/PHP/" . PHP_VERSION . "\r\n";

        $username = $this->config->get('username', null, $channel);

        $password = $this->config->get('password', null, $channel);

        if ($username && $password) {

            $tmp = base64_encode("$username:$password");

            $request .= "Authorization: Basic $tmp\r\n";

        }

        if ($proxy_host != '' && $proxy_user != '') {

            $request .= 'Proxy-Authorization: Basic ' .

                base64_encode($proxy_user . ':' . $proxy_pass) . "\r\n";

        }

        if ($accept) {

            $request .= 'Accept: ' . implode(', ', $accept) . "\r\n";

        }

        $request .= "Accept-Encoding:\r\n";

        $request .= "Connection: close\r\n";

        $request .= "\r\n";

        if ($proxy_host != '') {

            $fp = @fsockopen($proxy_host, $proxy_port, $errno, $errstr, 15);

            if (!$fp) {

                return PEAR::raiseError("Connection to `$proxy_host:$proxy_port' failed: $errstr", -9276);

            }

        } else {

            if ($schema === 'https') {

                $host = 'ssl://' . $host;

            }

            $fp = @fsockopen($host, $port, $errno, $errstr);

            if (!$fp) {

                return PEAR::raiseError("Connection to `$host:$port' failed: $errstr", $errno);

            }

        }

        fwrite($fp, $request);

        $headers = array();

        $reply   = 0;

        while ($line = trim(fgets($fp, 1024))) {

            if (preg_match('/^([^:]+):\s+(.*)\s*\\z/', $line, $matches)) {

                $headers[strtolower($matches[1])] = trim($matches[2]);

            } elseif (preg_match('|^HTTP/1.[01] ([0-9]{3}) |', $line, $matches)) {

                $reply = (int)$matches[1];

                if ($reply == 304 && ($lastmodified || ($lastmodified === false))) {

                    return false;

                }

                if (!in_array($reply, array(200, 301, 302, 303, 305, 307))) {

                    return PEAR::raiseError("File $schema://$host:$port$path not valid (received: $line)");

                }

            }

        }

        if ($reply != 200) {

            if (!isset($headers['location'])) {

                return PEAR::raiseError("File $schema://$host:$port$path not valid (redirected but no location)");

            }

            if ($wasredirect > 4) {

                return PEAR::raiseError("File $schema://$host:$port$path not valid (redirection looped more than 5 times)");

            }

            $redirect = $wasredirect + 1;

            return $this->downloadHttp($headers['location'], $lastmodified, $accept, $channel);

        }

        $length = isset($headers['content-length']) ? $headers['content-length'] : -1;

        $data = '';

        while ($chunk = @fread($fp, 8192)) {

            $data .= $chunk;

        }

        fclose($fp);

        if ($lastmodified === false || $lastmodified) {

            if (isset($headers['etag'])) {

                $lastmodified = array('ETag' => $headers['etag']);

            }

            if (isset($headers['last-modified'])) {

                if (is_array($lastmodified)) {

                    $lastmodified['Last-Modified'] = $headers['last-modified'];

                } else {

                    $lastmodified = $headers['last-modified'];

                }

            }

            return array($data, $lastmodified, $headers);

        }

        return $data;

    }

}