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/>.

namespace mod_bigbluebuttonbn\local\proxy;

use cache;

use completion_info;

use Exception;

use mod_bigbluebuttonbn\completion\custom_completion;

use mod_bigbluebuttonbn\instance;

use mod_bigbluebuttonbn\local\config;

use mod_bigbluebuttonbn\local\exceptions\bigbluebutton_exception;

use mod_bigbluebuttonbn\local\exceptions\server_not_available_exception;

use moodle_url;

use stdClass;

use user_picture;

/**

 * The bigbluebutton proxy class.

 *

 * This class acts as a proxy between Moodle and the BigBlueButton API server,

 * and handles all requests relating to the server and meetings.

 *

 * @package   mod_bigbluebuttonbn

 * @copyright 2010 onwards, Blindside Networks Inc

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

 * @author    Jesus Federico  (jesus [at] blindsidenetworks [dt] com)

 */

class bigbluebutton_proxy extends proxy_base {

    /**

     * Minimum poll interval for remote bigbluebutton server in seconds.

     */

    const MIN_POLL_INTERVAL = 2;

    /**

     * Default poll interval for remote bigbluebutton server in seconds.

     */

    const DEFAULT_POLL_INTERVAL = 5;

    /**

     * Builds and returns a url for joining a BigBlueButton meeting.

     *

     * @param instance $instance

     * @param string|null $createtime

     *

     * @return string

     */

    public static function get_join_url(

        instance $instance,

        ?string $createtime

    ): string {

        return self::internal_get_join_url($instance, $createtime);

    }

    /**

     * Builds and returns a url for joining a BigBlueButton meeting.

     *

     * @param instance $instance

     * @param string|null $createtime

     * @param string $username

     * @return string

     */

    public static function get_guest_join_url(

        instance $instance,

        ?string $createtime,

        string $username

    ): string {

        return self::internal_get_join_url($instance, $createtime, $username, true);

    }

    /**

     * Internal helper method to builds and returns a url for joining a BigBlueButton meeting.

     *

     * @param instance $instance

     * @param string|null $jointime = null

     * @param string|null $userfullname

     * @param bool $isguestjoin

     * @return string

     */

    private static function internal_get_join_url(

        instance $instance,

        ?string $jointime,

        string $userfullname = null,

        bool $isguestjoin = false

    ): string {

        $data = [

            'meetingID' => $instance->get_meeting_id(),

            'fullName' => $userfullname ?? $instance->get_user_fullname(),

            'password' => $instance->get_current_user_password(),

            'logoutURL' => $isguestjoin ? $instance->get_guest_access_url()->out(false) : $instance->get_logout_url()->out(false),

            'role' => $instance->get_current_user_role()

        ];

        if (!$isguestjoin) {

            $data['userID'] = $instance->get_user_id();

            $data['guest'] = "false";

        } else {

            $data['guest'] = "true";

        }

        if (!is_null($jointime)) {

            $data['createTime'] = $jointime;

        }

        $currentlang = current_language();

        if (!empty(trim($currentlang))) {

            $data['userdata-bbb_override_default_locale'] = $currentlang;

        }

        if ($instance->is_profile_picture_enabled()) {

            $user = $instance->get_user();

            if (!empty($user->picture)) {

                $data['avatarURL'] = self::get_avatar_url($user)->out(false);

            }

        }

        return self::action_url('join', $data, [], $instance->get_instance_id());

    }

    /**

     * Get user avatar URL

     *

     * @param stdClass $user

     * @return moodle_url

     */

    private static function get_avatar_url(stdClass $user): moodle_url {

        global $PAGE;

        $userpicture = new user_picture($user);

        $userpicture->includetoken = true;

        $userpicture->size = 3; // Size f3.

        return $userpicture->get_url($PAGE);

    }

    /**

     * Perform api request on BBB.

     *

     * @return null|string

     */

    public static function get_server_version(): ?string {

        $cache = cache::make('mod_bigbluebuttonbn', 'serverinfo');

        $serverversion = $cache->get('serverversion');

        if (!$serverversion) {

            $xml = self::fetch_endpoint_xml('');

            if (!$xml || $xml->returncode != 'SUCCESS') {

                return null;

            }

            if (!isset($xml->version)) {

                return null;

            }

            $serverversion = (string) $xml->version;

            $cache->set('serverversion', $serverversion);

        }

        return (double) $serverversion;

    }

    /**

     * Helper for getting the owner userid of a bigbluebuttonbn instance.

     *

     * @param stdClass $bigbluebuttonbn BigBlueButtonBN instance

     * @return int ownerid (a valid user id or null if not registered/found)

     */

    public static function get_instance_ownerid(stdClass $bigbluebuttonbn): int {

        global $DB;

        $filters = [

            'bigbluebuttonbnid' => $bigbluebuttonbn->id,

            'log' => 'Add',

        ];

        return (int) $DB->get_field('bigbluebuttonbn_logs', 'userid', $filters);

    }

    /**

     * Helper evaluates if a voicebridge number is unique.

     *

     * @param int $instance

     * @param int $voicebridge

     * @return bool

     */

    public static function is_voicebridge_number_unique(int $instance, int $voicebridge): bool {

        global $DB;

        if ($voicebridge == 0) {

            return true;

        }

        $select = 'voicebridge = ' . $voicebridge;

        if ($instance != 0) {

            $select .= ' AND id <>' . $instance;

        }

        if (!$DB->get_records_select('bigbluebuttonbn', $select)) {

            return true;

        }

        return false;

    }

    /**

     * Helper function validates a remote resource.

     *

     * @param string $url

     * @return bool

     */

    public static function is_remote_resource_valid(string $url): bool {

        $urlhost = parse_url($url, PHP_URL_HOST);

        $serverurlhost = parse_url(\mod_bigbluebuttonbn\local\config::get('server_url'), PHP_URL_HOST);

        if ($urlhost == $serverurlhost) {

            // Skip validation when the recording URL host is the same as the configured BBB server.

            return true;

        }

        $cache = cache::make('mod_bigbluebuttonbn', 'validatedurls');

        if ($cachevalue = $cache->get($urlhost)) {

            // Skip validation when the recording URL was already validated.

            return $cachevalue == 1;

        }

        $curl = new curl();

        $curl->head($url);

        $isvalid = false;

        if ($info = $curl->get_info()) {

            if ($info['http_code'] == 200) {

                $isvalid = true;

            } else {

                debugging(

                    "Resources hosted by {$urlhost} are unreachable. Server responded with {$info['http_code']}",

                    DEBUG_DEVELOPER

                );

                $isvalid = false;

            }

            // Note: When a cache key is not found, it returns false.

            // We need to distinguish between a result not found, and an invalid result.

            $cache->set($urlhost, $isvalid ? 1 : 0);

        }

        return $isvalid;

    }

    /**

     * Helper function enqueues one user for being validated as for completion.

     *

     * @param stdClass $bigbluebuttonbn

     * @param int $userid

     * @return void

     */

    public static function enqueue_completion_event(stdClass $bigbluebuttonbn, int $userid): void {

        try {

            // Create the instance of completion_update_state task.

            $task = new \mod_bigbluebuttonbn\task\completion_update_state();

            // Add custom data.

            $data = [

                'bigbluebuttonbn' => $bigbluebuttonbn,

                'userid' => $userid,

            ];

            $task->set_custom_data($data);

            // CONTRIB-7457: Task should be executed by a user, maybe Teacher as Student won't have rights for overriding.

            // $ task -> set_userid ( $ user -> id );.

            // Enqueue it.

            \core\task\manager::queue_adhoc_task($task);

        } catch (Exception $e) {

            mtrace("Error while enqueuing completion_update_state task. " . (string) $e);

        }

    }

    /**

     * Helper function enqueues completion trigger.

     *

     * @param stdClass $bigbluebuttonbn

     * @param int $userid

     * @return void

     */

    public static function update_completion_state(stdClass $bigbluebuttonbn, int $userid) {

        global $CFG;

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

        list($course, $cm) = get_course_and_cm_from_instance($bigbluebuttonbn, 'bigbluebuttonbn');

        $completion = new completion_info($course);

        if (!$completion->is_enabled($cm)) {

            mtrace("Completion not enabled");

            return;

        }

        $bbbcompletion = new custom_completion($cm, $userid);

        if ($bbbcompletion->get_overall_completion_state()) {

            mtrace("Completion for userid $userid and bigbluebuttonid {$bigbluebuttonbn->id} updated.");

            $completion->update_state($cm, COMPLETION_COMPLETE, $userid, true);

        } else {

            // Still update state to current value (prevent unwanted caching).

            $completion->update_state($cm, COMPLETION_UNKNOWN, $userid);

            mtrace("Activity not completed for userid $userid and bigbluebuttonid {$bigbluebuttonbn->id}.");

        }

    }

    /**

     * Helper function returns an array with the profiles (with features per profile) for the different types

     * of bigbluebuttonbn instances.

     *

     * @return array

     */

    public static function get_instance_type_profiles(): array {

        $instanceprofiles = [

            instance::TYPE_ALL => [

                'id' => instance::TYPE_ALL,

                'name' => get_string('instance_type_default', 'bigbluebuttonbn'),

                'features' => ['all']

            ],

            instance::TYPE_ROOM_ONLY => [

                'id' => instance::TYPE_ROOM_ONLY,

                'name' => get_string('instance_type_room_only', 'bigbluebuttonbn'),

                'features' => ['showroom', 'welcomemessage', 'voicebridge', 'waitformoderator', 'userlimit',

                    'recording', 'sendnotifications', 'lock', 'preuploadpresentation', 'permissions', 'schedule', 'groups',

                    'modstandardelshdr', 'availabilityconditionsheader', 'tagshdr', 'competenciessection',

                    'completionattendance', 'completionengagement', 'availabilityconditionsheader']

            ],

            instance::TYPE_RECORDING_ONLY => [

                'id' => instance::TYPE_RECORDING_ONLY,

                'name' => get_string('instance_type_recording_only', 'bigbluebuttonbn'),

                'features' => ['showrecordings', 'importrecordings', 'availabilityconditionsheader']

            ],

        ];

        return $instanceprofiles;

    }

    /**

     * Helper function returns an array with the profiles (with features per profile) for the different types

     * of bigbluebuttonbn instances that the user is allowed to create.

     *

     * @param bool $room

     * @param bool $recording

     *

     * @return array

     */

    public static function get_instance_type_profiles_create_allowed(bool $room, bool $recording): array {

        $profiles = self::get_instance_type_profiles();

        if (!$room) {

            unset($profiles[instance::TYPE_ROOM_ONLY]);

            unset($profiles[instance::TYPE_ALL]);

        }

        if (!$recording) {

            unset($profiles[instance::TYPE_RECORDING_ONLY]);

            unset($profiles[instance::TYPE_ALL]);

        }

        return $profiles;

    }

    /**

     * Helper function returns an array with the profiles (with features per profile) for the different types

     * of bigbluebuttonbn instances.

     *

     * @param array $profiles

     *

     * @return array

     */

    public static function get_instance_profiles_array(array $profiles = []): array {

        $profilesarray = [];

        foreach ($profiles as $key => $profile) {

            $profilesarray[$profile['id']] = $profile['name'];

        }

        return $profilesarray;

    }

    /**

     * Return the status of an activity [open|not_started|ended].

     *

     * @param instance $instance

     * @return string

     */

    public static function view_get_activity_status(instance $instance): string {

        $now = time();

        if (!empty($instance->get_instance_var('openingtime')) && $now < $instance->get_instance_var('openingtime')) {

            // The activity has not been opened.

            return 'not_started';

        }

        if (!empty($instance->get_instance_var('closingtime')) && $now > $instance->get_instance_var('closingtime')) {

            // The activity has been closed.

            return 'ended';

        }

        // The activity is open.

        return 'open';

    }

    /**

     * Ensure that the remote server was contactable.

     *

     * @param instance $instance

     */

    public static function require_working_server(instance $instance): void {

        $version = null;

        try {

            $version = self::get_server_version();

        } catch (server_not_available_exception $e) {

            self::handle_server_not_available($instance);

        }

        if (empty($version)) {

            self::handle_server_not_available($instance);

        }

    }

    /**

     * Handle the server not being available.

     *

     * @param instance $instance

     */

    public static function handle_server_not_available(instance $instance): void {

        \core\notification::add(

            self::get_server_not_available_message($instance),

            \core\notification::ERROR

        );

        redirect(self::get_server_not_available_url($instance));

    }

    /**

     * Get message when server not available

     *

     * @param instance $instance

     * @return string

     */

    public static function get_server_not_available_message(instance $instance): string {

        if ($instance->is_admin()) {

            return get_string('view_error_unable_join', 'mod_bigbluebuttonbn');

        } else if ($instance->is_moderator()) {

            return get_string('view_error_unable_join_teacher', 'mod_bigbluebuttonbn');

        } else {

            return get_string('view_error_unable_join_student', 'mod_bigbluebuttonbn');

        }

    }

    /**

     * Get URL to the page displaying that the server is not available

     *

     * @param instance $instance

     * @return string

     */

    public static function get_server_not_available_url(instance $instance): string {

        if ($instance->is_admin()) {

            return new moodle_url('/admin/settings.php', ['section' => 'modsettingbigbluebuttonbn']);

        } else if ($instance->is_moderator()) {

            return new moodle_url('/course/view.php', ['id' => $instance->get_course_id()]);

        } else {

            return new moodle_url('/course/view.php', ['id' => $instance->get_course_id()]);

        }

    }

    /**

     * Create a Meeting

     *

     * @param array $data

     * @param array $metadata

     * @param string|null $presentationname

     * @param string|null $presentationurl

     * @param int|null $instanceid

     * @return array

     * @throws bigbluebutton_exception

     */

    public static function create_meeting(

        array $data,

        array $metadata,

        ?string $presentationname = null,

        ?string $presentationurl = null,

        ?int $instanceid = null

    ): array {

        $createmeetingurl = self::action_url('create', $data, $metadata, $instanceid);

        $curl = new curl();

        if (!is_null($presentationname) && !is_null($presentationurl)) {

            $payload = "<?xml version='1.0' encoding='UTF-8'?><modules><module name='presentation'><document url='" .

                $presentationurl . "' /></module></modules>";

            $xml = $curl->post($createmeetingurl, $payload);

        } else {

            $xml = $curl->get($createmeetingurl);

        }

        self::assert_returned_xml($xml);

        if (empty($xml->meetingID)) {

            throw new bigbluebutton_exception('general_error_cannot_create_meeting');

        }

        if ($xml->hasBeenForciblyEnded === 'true') {

            throw new bigbluebutton_exception('index_error_forciblyended');

        }

        return [

            'meetingID' => (string) $xml->meetingID,

            'internalMeetingID' => (string) $xml->internalMeetingID,

            'attendeePW' => (string) $xml->attendeePW,

            'moderatorPW' => (string) $xml->moderatorPW

        ];

    }

    /**

     * Get meeting info for a given meeting id

     *

     * @param string $meetingid

     * @param int|null $instanceid

     * @return array

     */

    public static function get_meeting_info(string $meetingid, ?int $instanceid = null): array {

        $xmlinfo = self::fetch_endpoint_xml('getMeetingInfo', ['meetingID' => $meetingid], [], $instanceid);

        self::assert_returned_xml($xmlinfo, ['meetingid' => $meetingid]);

        return (array) $xmlinfo;

    }

    /**

     * Perform end meeting on BBB.

     *

     * @param string $meetingid

     * @param string $modpw

     * @param int|null $instanceid

     */

    public static function end_meeting(string $meetingid, string $modpw, ?int $instanceid = null): void {

        $xml = self::fetch_endpoint_xml('end', ['meetingID' => $meetingid, 'password' => $modpw], [], $instanceid);

        self::assert_returned_xml($xml, ['meetingid' => $meetingid]);

    }

    /**

     * Helper evaluates if the bigbluebutton server used belongs to blindsidenetworks domain.

     *

     * @return bool

     */

    public static function is_bn_server() {

        if (config::get('bn_server')) {

            return true;

        }

        $parsedurl = parse_url(config::get('server_url'));

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

            return false;

        }

        $h = $parsedurl['host'];

        $hends = explode('.', $h);

        $hendslength = count($hends);

        return ($hends[$hendslength - 1] == 'com' && $hends[$hendslength - 2] == 'blindsidenetworks');

    }

    /**

     * Get the poll interval as it is set in the configuration

     *

     * If configuration value is under the threshold of {@see self::MIN_POLL_INTERVAL},

     * then return the {@see self::MIN_POLL_INTERVAL} value.

     *

     * @return int the poll interval in seconds

     */

    public static function get_poll_interval(): int {

        $pollinterval = intval(config::get('poll_interval'));

        if ($pollinterval < self::MIN_POLL_INTERVAL) {

            $pollinterval = self::MIN_POLL_INTERVAL;

        }

        return $pollinterval;

    }

}