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/>.

/**

 * New role XML processing.

 *

 * @package    core_role

 * @copyright  2013 Petr Skoda {@link http://skodak.org}

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

 */

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

/**

 * XML role file manipulation class.

 *

 * @package    core_role

 * @copyright  2013 Petr Skoda {@link http://skodak.org}

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

 */

class core_role_preset {

    /**

     * Send role export xml file to browser.

     *

     * @param int $roleid

     * @return void does not return, send the file to output

     */

    public static function send_export_xml($roleid) {

        global $CFG, $DB;

        require_once($CFG->libdir . '/filelib.php');

        $role = $DB->get_record('role', array('id'=>$roleid), '*', MUST_EXIST);

        if ($role->shortname) {

            $filename = $role->shortname.'.xml';

        } else {

            $filename = 'role.xml';

        }

        $xml = self::get_export_xml($roleid);

        send_file($xml, $filename, 0, false, true, true);

        die();

    }

    /**

     * Generate role export xml file.

     *

     * @param $roleid

     * @return string

     */

    public static function get_export_xml($roleid) {

        global $DB;

        $role = $DB->get_record('role', array('id'=>$roleid), '*', MUST_EXIST);

        $dom = new DOMDocument('1.0', 'UTF-8');

        $top = $dom->createElement('role');

        $dom->appendChild($top);

        $top->appendChild($dom->createElement('shortname', $role->shortname));

        $top->appendChild($dom->createElement('name', htmlspecialchars($role->name, ENT_COMPAT | ENT_HTML401, 'UTF-8')));

        $top->appendChild($dom->createElement('description', htmlspecialchars($role->description, ENT_COMPAT | ENT_HTML401,

                'UTF-8')));

        $top->appendChild($dom->createElement('archetype', $role->archetype));

        $contextlevels = $dom->createElement('contextlevels');

        $top->appendChild($contextlevels);

        foreach (get_role_contextlevels($roleid) as $level) {

            $name = context_helper::get_class_for_level($level);

            if (strpos($name, 'core\\context\\') === 0) {

                // Use short names of standard contexts for backwards compatibility.

                $value = preg_replace('/^core\\\\context\\\\/', '', $name);

            } else {

                // Must be a custom plugin level, use numbers to work around

                // potential duplicate short names of contexts in add-ons.

                $value = $level;

            }

            $contextlevels->appendChild($dom->createElement('level', $value));

        }

        foreach (array('assign', 'override', 'switch', 'view') as $type) {

            $allows = $dom->createElement('allow'.$type);

            $top->appendChild($allows);

            $records = $DB->get_records('role_allow_'.$type, array('roleid'=>$roleid), "allow$type ASC");

            foreach ($records as $record) {

                if (!$ar = $DB->get_record('role', array('id'=>$record->{'allow'.$type}))) {

                    continue;

                }

                $allows->appendChild($dom->createElement('shortname', $ar->shortname));

            }

        }

        $permissions = $dom->createElement('permissions');

        $top->appendChild($permissions);

        $capabilities = $DB->get_records_sql_menu(

            "SELECT capability, permission

               FROM {role_capabilities}

              WHERE contextid = :syscontext AND roleid = :roleid

           ORDER BY capability ASC",

            array('syscontext'=>context_system::instance()->id, 'roleid'=>$roleid));

        $allcapabilities = $DB->get_records('capabilities', array(), 'name ASC');

        foreach ($allcapabilities as $cap) {

            if (!isset($capabilities[$cap->name])) {

                $permissions->appendChild($dom->createElement('inherit', $cap->name));

            }

        }

        foreach ($capabilities as $capability => $permission) {

            if ($permission == CAP_ALLOW) {

                $permissions->appendChild($dom->createElement('allow', $capability));

            }

        }

        foreach ($capabilities as $capability => $permission) {

            if ($permission == CAP_PREVENT) {

                $permissions->appendChild($dom->createElement('prevent', $capability));

            }

        }

        foreach ($capabilities as $capability => $permission) {

            if ($permission == CAP_PROHIBIT) {

                $permissions->appendChild($dom->createElement('prohibit', $capability));

            }

        }

        return $dom->saveXML();

    }

    /**

     * Is this XML valid role preset?

     *

     * @param string $xml

     * @return bool

     */

    public static function is_valid_preset($xml) {

        $dom = new DOMDocument();

        if (!$dom->loadXML($xml)) {

            return false;

        } else {

            $val = @$dom->schemaValidate(__DIR__.'/../role_schema.xml');

            if (!$val) {

                return false;

            }

        }

        return true;

    }

    /**

     * Parse role preset xml file.

     *

     * @param string $xml

     * @return array role info, null on error

     */

    public static function parse_preset($xml) {

        global $DB;

        $info = array();

        if (!self::is_valid_preset($xml)) {

            return null;

        }

        $dom = new DOMDocument();

        $dom->loadXML($xml);

        $info['shortname'] = self::get_node_value($dom, '/role/shortname');

        if (isset($info['shortname'])) {

            $info['shortname'] = strtolower(clean_param($info['shortname'], PARAM_ALPHANUMEXT));

        }

        $info['name'] = self::get_node_value($dom, '/role/name');

        if (isset($value)) {

            $info['name'] = clean_param($info['name'], PARAM_TEXT);

        }

        $info['description'] = self::get_node_value($dom, '/role/description');

        if (isset($value)) {

            $info['description'] = clean_param($info['description'], PARAM_CLEANHTML);

        }

        $info['archetype'] = self::get_node_value($dom, '/role/archetype');

        if (isset($value)) {

            $archetypes = get_role_archetypes();

            if (!isset($archetypes[$info['archetype']])) {

                $info['archetype'] = null;

            }

        }

        $values = self::get_node_children_values($dom, '/role/contextlevels', 'level');

        if (isset($values)) {

            $info['contextlevels'] = array();

            $levelmap = array_flip(context_helper::get_all_levels());

            foreach ($values as $value) {

                // Numbers and short names are supported since Moodle 4.2.

                $classname = \core\context_helper::parse_external_level($value);

                if ($classname) {

                    $cl = $classname::LEVEL;

                    $info['contextlevels'][$cl] = $cl;

                }

            }

        }

        foreach (array('assign', 'override', 'switch', 'view') as $type) {

            $values = self::get_node_children_values($dom, '/role/allow'.$type, 'shortname');

            if (!isset($values)) {

                $info['allow'.$type] = null;

                continue;

            }

            $info['allow'.$type] = array();

            foreach ($values as $value) {

                if ($value === $info['shortname']) {

                    array_unshift($info['allow'.$type], -1); // Means self.

                }

                if ($role = $DB->get_record('role', array('shortname'=>$value))) {

                    $info['allow'.$type][] = $role->id;

                    continue;

                }

            }

        }

        $info['permissions'] = array();

        $values = self::get_node_children_values($dom, '/role/permissions', 'inherit');

        if (isset($values)) {

            foreach ($values as $value) {

                if ($value = clean_param($value, PARAM_CAPABILITY)) {

                    $info['permissions'][$value] = CAP_INHERIT;

                }

            }

        }

        $values = self::get_node_children_values($dom, '/role/permissions', 'allow');

        if (isset($values)) {

            foreach ($values as $value) {

                if ($value = clean_param($value, PARAM_CAPABILITY)) {

                    $info['permissions'][$value] = CAP_ALLOW;

                }

            }

        }

        $values = self::get_node_children_values($dom, '/role/permissions', 'prevent');

        if (isset($values)) {

            foreach ($values as $value) {

                if ($value = clean_param($value, PARAM_CAPABILITY)) {

                    $info['permissions'][$value] = CAP_PREVENT;

                }

            }

        }

        $values = self::get_node_children_values($dom, '/role/permissions', 'prohibit');

        if (isset($values)) {

            foreach ($values as $value) {

                if ($value = clean_param($value, PARAM_CAPABILITY)) {

                    $info['permissions'][$value] = CAP_PROHIBIT;

                }

            }

        }

        return $info;

    }

    protected static function get_node(DOMDocument $dom, $path) {

        $parts = explode('/', $path);

        $elname = end($parts);

        $nodes = $dom->getElementsByTagName($elname);

        if ($nodes->length == 0) {

            return null;

        }

        foreach ($nodes as $node) {

            if ($node->getNodePath() === $path) {

                return $node;

            }

        }

        return null;

    }

    protected static function get_node_value(DOMDocument $dom, $path) {

        if (!$node = self::get_node($dom, $path)) {

            return null;

        }

        return $node->nodeValue;

    }

    protected static function get_node_children(DOMDocument $dom, $path, $tagname) {

        if (!$node = self::get_node($dom, $path)) {

            return null;

        }

        $return = array();

        foreach ($node->childNodes as $child) {

            if ($child->nodeName === $tagname) {

                $return[] = $child;

            }

        }

        return $return;

    }

    protected static function get_node_children_values(DOMDocument $dom, $path, $tagname) {

        $children = self::get_node_children($dom, $path, $tagname);

        if ($children === null) {

            return null;

        }

        $return = array();

        foreach ($children as $child) {

            $return[] = $child->nodeValue;

        }

        return $return;

    }

}