Proyectos de Subversion Moodle

<?php

// This file is part of Moodle - http://moodle.org/

//

// Moodle is free software: you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

//

// Moodle is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU General Public License for more details.

//

// You should have received a copy of the GNU General Public License

// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**

 * @package    moodlecore

 * @subpackage backup-helper

 * @copyright  2010 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

defined('MOODLE_INTERNAL') || die();

/**

 * Non instantiable helper class providing general helper methods for backup/restore

 *

 * This class contains various general helper static methods available for backup/restore

 *

 * TODO: Finish phpdocs

 */

abstract class backup_general_helper extends backup_helper {

    /**

     * Calculate one checksum for any array/object. Works recursively

     */

    public static function array_checksum_recursive($arr) {

        $checksum = ''; // Init checksum

        // Check we are going to process one array always, objects must be cast before

        if (!is_array($arr)) {

            throw new backup_helper_exception('array_expected');

        }

        foreach ($arr as $key => $value) {

            if ($value instanceof checksumable) {

                $checksum = md5($checksum . '-' . $key . '-' . $value->calculate_checksum());

            } else if (is_object($value)) {

                $checksum = md5($checksum . '-' . $key . '-' . self::array_checksum_recursive((array)$value));

            } else if (is_array($value)) {

                $checksum = md5($checksum . '-' . $key . '-' . self::array_checksum_recursive($value));

            } else {

                $checksum = md5($checksum . '-' . $key . '-' . $value);

            }

        }

        return $checksum;

    }

    /**

     * Load all the blocks information needed for a given path within moodle2 backup

     *

     * This function, given one full path (course, activities/xxxx) will look for all the

     * blocks existing in the backup file, returning one array used to build the

     * proper restore plan by the @restore_plan_builder

     */

    public static function get_blocks_from_path($path) {

        global $DB;

        $blocks = array(); // To return results

        static $availableblocks = array(); // Get and cache available blocks

        if (empty($availableblocks)) {

            $availableblocks = array_keys(core_component::get_plugin_list('block'));

        }

        $path = $path . '/blocks'; // Always look under blocks subdir

        if (!is_dir($path)) {

            return array();

        }

        if (!$dir = opendir($path)) {

            return array();

        }

        while (false !== ($file = readdir($dir))) {

            if ($file == '.' || $file == '..') { // Skip dots

                continue;

            }

            if (is_dir($path .'/' . $file)) { // Dir found, check it's a valid block

                if (!file_exists($path .'/' . $file . '/block.xml')) { // Skip if xml file not found

                    continue;

                }

                // Extract block name

                $blockname = preg_replace('/(.*)_\d+/', '\\1', $file);

                // Check block exists and is installed

                if (in_array($blockname, $availableblocks) && $DB->record_exists('block', array('name' => $blockname))) {

                    $blocks[$path .'/' . $file] = $blockname;

                }

            }

        }

        closedir($dir);

        return $blocks;

    }

    /**

     * Load and format all the needed information from moodle_backup.xml

     *

     * This function loads and process all the moodle_backup.xml

     * information, composing a big information structure that will

     * be the used by the plan builder in order to generate the

     * appropiate tasks / steps / settings

     */

    public static function get_backup_information($tempdir) {

        global $CFG;

        // Make a request cache and store the data in there.

        static $cachesha1 = null;

        static $cache = null;

        $info = new stdclass(); // Final information goes here

        $backuptempdir = make_backup_temp_directory('', false);

        $moodlefile = $backuptempdir . '/' . $tempdir . '/moodle_backup.xml';

        if (!file_exists($moodlefile)) { // Shouldn't happen ever, but...

            throw new backup_helper_exception('missing_moodle_backup_xml_file', $moodlefile);

        }

        $moodlefilesha1 = sha1_file($moodlefile);

        if ($moodlefilesha1 === $cachesha1) {

            return clone $cache;

        }

        // Load the entire file to in-memory array

        $xmlparser = new progressive_parser();

        $xmlparser->set_file($moodlefile);

        $xmlprocessor = new restore_moodlexml_parser_processor();

        $xmlparser->set_processor($xmlprocessor);

        $xmlparser->process();

        $infoarr = $xmlprocessor->get_all_chunks();

        if (count($infoarr) !== 1) { // Shouldn't happen ever, but...

            throw new backup_helper_exception('problem_parsing_moodle_backup_xml_file');

        }

        $infoarr = $infoarr[0]['tags']; // for commodity

        // Let's build info

        $info->moodle_version = $infoarr['moodle_version'];

        $info->moodle_release = $infoarr['moodle_release'];

        $info->backup_version = $infoarr['backup_version'];

        $info->backup_release = $infoarr['backup_release'];

        $info->backup_date    = $infoarr['backup_date'];

        $info->mnet_remoteusers         = $infoarr['mnet_remoteusers'];

        $info->original_wwwroot         = $infoarr['original_wwwroot'];

        $info->original_site_identifier_hash = $infoarr['original_site_identifier_hash'];

        $info->original_course_id        = $infoarr['original_course_id'];

        $info->original_course_fullname  = $infoarr['original_course_fullname'];

        $info->original_course_shortname = $infoarr['original_course_shortname'];

        $info->original_course_startdate = $infoarr['original_course_startdate'];

        // Old versions may not have this.

        if (isset($infoarr['original_course_enddate'])) {

            $info->original_course_enddate  = $infoarr['original_course_enddate'];

        }

        $info->original_course_contextid = $infoarr['original_course_contextid'];

        $info->original_system_contextid = $infoarr['original_system_contextid'];

        // Moodle backup file don't have this option before 2.3

        if (!empty($infoarr['include_file_references_to_external_content'])) {

            $info->include_file_references_to_external_content = 1;

        } else {

            $info->include_file_references_to_external_content = 0;

        }

        // Introduced in Moodle 2.9.

        $info->original_course_format = '';

        if (!empty($infoarr['original_course_format'])) {

            $info->original_course_format = $infoarr['original_course_format'];

        }

        // include_files is a new setting in 2.6.

        if (isset($infoarr['include_files'])) {

            $info->include_files = $infoarr['include_files'];

        } else {

            $info->include_files = 1;

        }

        $info->type   =  $infoarr['details']['detail'][0]['type'];

        $info->format =  $infoarr['details']['detail'][0]['format'];

        $info->mode   =  $infoarr['details']['detail'][0]['mode'];

        // Build the role mappings custom object

        $rolemappings = new stdclass();

        $rolemappings->modified = false;

        $rolemappings->mappings = array();

        $info->role_mappings = $rolemappings;

        // Some initially empty containers

        $info->sections = array();

        $info->activities = array();

        // Now the contents

        $contentsarr = $infoarr['contents'];

        if (isset($contentsarr['course']) && isset($contentsarr['course'][0])) {

            $info->course = new stdclass();

            $info->course = (object)$contentsarr['course'][0];

            $info->course->settings = array();

        }

        if (isset($contentsarr['sections']) && isset($contentsarr['sections']['section'])) {

            $sectionarr = $contentsarr['sections']['section'];

            foreach ($sectionarr as $section) {

                $section = (object)$section;

                $section->settings = array();

                $sections[basename($section->directory)] = $section;

            }

            $info->sections = $sections;

        }

        if (isset($contentsarr['activities']) && isset($contentsarr['activities']['activity'])) {

            $activityarr = $contentsarr['activities']['activity'];

            foreach ($activityarr as $activity) {

                $activity = (object)$activity;

                $activity->settings = array();

                $activities[basename($activity->directory)] = $activity;

            }

            $info->activities = $activities;

        }

        $info->root_settings = array(); // For root settings

        // Now the settings, putting each one under its owner

        $settingsarr = $infoarr['settings']['setting'];

        foreach($settingsarr as $setting) {

            switch ($setting['level']) {

                case 'root':

                    $info->root_settings[$setting['name']] = $setting['value'];

                    break;

                case 'course':

                    $info->course->settings[$setting['name']] = $setting['value'];

                    break;

                case 'section':

                    $info->sections[$setting['section']]->settings[$setting['name']] = $setting['value'];

                    break;

                case 'activity':

                    $info->activities[$setting['activity']]->settings[$setting['name']] = $setting['value'];

                    break;

                default: // Shouldn't happen but tolerated for portability of customized backups.

                    debugging("Unknown backup setting level: {$setting['level']}", DEBUG_DEVELOPER);

                    break;

            }

        }

        $cache = clone $info;

        $cachesha1 = $moodlefilesha1;

        return $info;

    }

    /**

     * Load and format all the needed information from a backup file.

     *

     * This will only extract the moodle_backup.xml file from an MBZ

     * file and then call {@link self::get_backup_information()}.

     *

     * This can be a long-running (multi-minute) operation for large backups.

     * Pass a $progress value to receive progress updates.

     *

     * @param string $filepath absolute path to the MBZ file.

     * @param file_progress $progress Progress updates

     * @return stdClass containing information.

     * @since Moodle 2.4

     */

    public static function get_backup_information_from_mbz($filepath, file_progress $progress = null) {

        global $CFG;

        if (!is_readable($filepath)) {

            throw new backup_helper_exception('missing_moodle_backup_file', $filepath);

        }

        // Extract moodle_backup.xml.

        $tmpname = 'info_from_mbz_' . time() . '_' . random_string(4);

        $tmpdir = make_backup_temp_directory($tmpname);

        $fp = get_file_packer('application/vnd.moodle.backup');

        $extracted = $fp->extract_to_pathname($filepath, $tmpdir, array('moodle_backup.xml'), $progress);

        $moodlefile =  $tmpdir . '/' . 'moodle_backup.xml';

        if (!$extracted || !is_readable($moodlefile)) {

            throw new backup_helper_exception('missing_moodle_backup_xml_file', $moodlefile);

        }

        // Read the information and delete the temporary directory.

        $info = self::get_backup_information($tmpname);

        remove_dir($tmpdir);

        return $info;

    }

    /**

     * Given the information fetched from moodle_backup.xml file

     * decide if we are restoring in the same site the backup was

     * generated or no. Behavior of various parts of restore are

     * dependent of this.

     *

     * Backups created natively in 2.0 and later declare the hashed

     * site identifier. Backups created by conversion from a 1.9

     * backup do not declare such identifier, so there is a fallback

     * to wwwroot comparison. See MDL-16614.

     */

    public static function backup_is_samesite($info) {

        global $CFG;

        $hashedsiteid = md5(get_site_identifier());

        if (isset($info->original_site_identifier_hash) && !empty($info->original_site_identifier_hash)) {

            return $info->original_site_identifier_hash == $hashedsiteid;

        } else {

            return $info->original_wwwroot == $CFG->wwwroot;

        }

    }

    /**

     * Detects the format of the given unpacked backup directory

     *

     * @param string $tempdir the name of the backup directory

     * @return string one of backup::FORMAT_xxx constants

     */

    public static function detect_backup_format($tempdir) {

        global $CFG;

        require_once($CFG->dirroot . '/backup/util/helper/convert_helper.class.php');

        if (convert_helper::detect_moodle2_format($tempdir)) {

            return backup::FORMAT_MOODLE;

        }

        // see if a converter can identify the format

        $converters = convert_helper::available_converters();

        foreach ($converters as $name) {

            $classname = "{$name}_converter";

            if (!class_exists($classname)) {

                throw new coding_exception("available_converters() is supposed to load

                    converter classes but class $classname not found");

            }

            $detected = call_user_func($classname .'::detect_format', $tempdir);

            if (!empty($detected)) {

                return $detected;

            }

        }

        return backup::FORMAT_UNKNOWN;

    }

}