MDL-67789 h5p: Save current state using xAPI State

Co-author: Andrew Lyons <andrew@moodle.com>

h5p/amd/src/repository.js

@@ -0,0 +1,99 @@
+// 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/>.
+
+/**
+ * Module to handle AJAX interactions.
+ *
+ * @module     core_h5p/repository
+ * @copyright  2023 Andrew Nicols <andrew@nicols.co.uk>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+import {call as fetchMany} from 'core/ajax';
+import * as config from 'core/config';
+
+/**
+ * Send a xAPI statement to LMS.
+ *
+ * @param {string} component
+ * @param {Object} statements
+ * @returns {Promise}
+ */
+export const postStatement = (component, statements) => fetchMany([{
+    methodname: 'core_xapi_statement_post',
+    args: {
+        component,
+        requestjson: JSON.stringify(statements),
+    }
+}])[0];
+
+/**
+ * Send a xAPI state to LMS.
+ *
+ * @param {string} component
+ * @param {string} activityId
+ * @param {Object} agent
+ * @param {string} stateId
+ * @param {string} stateData
+ */
+export const postState = (
+    component,
+    activityId,
+    agent,
+    stateId,
+    stateData,
+) => {
+    // Please note that we must use a Beacon send here.
+    // The XHR is not guaranteed because it will be aborted on page transition.
+    // https://developer.mozilla.org/en-US/docs/Web/API/Beacon_API
+    // Note: Moodle does not currently have a sendBeacon API endpoint.
+    const requestUrl = new URL(`${config.wwwroot}/lib/ajax/service.php`);
+    requestUrl.searchParams.set('sesskey', config.sesskey);
+
+    navigator.sendBeacon(requestUrl, JSON.stringify([{
+        index: 0,
+        methodname: 'core_xapi_post_state',
+        args: {
+            component,
+            activityId,
+            agent: JSON.stringify(agent),
+            stateId,
+            stateData,
+        }
+    }]));
+};
+
+/**
+ * Delete a xAPI state from LMS.
+ *
+ * @param {string} component
+ * @param {string} activityId
+ * @param {Object} agent
+ * @param {string} stateId
+ * @returns {Promise}
+ */
+export const deleteState = (
+    component,
+    activityId,
+    agent,
+    stateId,
+) => fetchMany([{
+    methodname: 'core_xapi_delete_state',
+    args: {
+        component,
+        activityId,
+        agent: JSON.stringify(agent),
+        stateId,
+    },
+}])[0];

h5p/classes/framework.php

@@ -16,6 +16,8 @@
 
 namespace core_h5p;
 
+use core_xapi\handler;
+use core_xapi\xapi_exception;
 use Moodle\H5PFrameworkInterface;
 use Moodle\H5PCore;
 
@@ -886,14 +888,6 @@ public function insertContent($content, $contentmainid = null) {
     public function updateContent($content, $contentmainid = null) {
         global $DB;
 
-        if (!isset($content['pathnamehash'])) {
-            $content['pathnamehash'] = '';
-        }
-
-        if (!isset($content['contenthash'])) {
-            $content['contenthash'] = '';
-        }
-
         // If the libraryid declared in the package is empty, get the latest version.
         if (empty($content['library']['libraryId'])) {
             $mainlibrary = $this->get_latest_library_version($content['library']['machineName']);
@@ -919,11 +913,19 @@ public function updateContent($content, $contentmainid = null) {
             'mainlibraryid' => $content['library']['libraryId'],
             'timemodified' => time(),
             'filtered' => null,
-            'pathnamehash' => $content['pathnamehash'],
-            'contenthash' => $content['contenthash']
         ];
 
+        if (isset($content['pathnamehash'])) {
+            $data['pathnamehash'] = $content['pathnamehash'];
+        }
+
+        if (isset($content['contenthash'])) {
+            $data['contenthash'] = $content['contenthash'];
+        }
+
         if (!isset($content['id'])) {
+            $data['pathnamehash'] = $data['pathnamehash'] ?? '';
+            $data['contenthash'] = $data['contenthash'] ?? '';
             $data['timecreated'] = $data['timemodified'];
             $id = $DB->insert_record('h5p', $data);
         } else {
@@ -941,7 +943,28 @@ public function updateContent($content, $contentmainid = null) {
      * @param int $contentid The h5p content id
      */
     public function resetContentUserData($contentid) {
-        // Currently, we do not store user data for a content.
+        global $DB;
+
+        // Get the component associated to the H5P content to reset.
+        $h5p = $DB->get_record('h5p', ['id' => $contentid]);
+        if (!$h5p) {
+            return;
+        }
+
+        $fs = get_file_storage();
+        $file = $fs->get_file_by_hash($h5p->pathnamehash);
+        if (!$file) {
+            return;
+        }
+
+        // Reset user data.
+        try {
+            $xapihandler = handler::create($file->get_component());
+            $xapihandler->reset_states($file->get_contextid());
+        } catch (xapi_exception $exception) {
+            // This component doesn't support xAPI State, so no content needs to be reset.
+            return;
+        }
     }
 
     /**
@@ -998,8 +1021,12 @@ public function copyLibraryUsage($contentid, $copyfromid, $contentmainid = null)
     public function deleteContentData($contentid) {
         global $DB;
 
+        // The user content should be reset (instead of removed), because this method is called when H5P content needs
+        // to be updated too (and the previous states must be kept, but reset).
+        $this->resetContentUserData($contentid);
+
         // Remove content.
-        $DB->delete_records('h5p', array('id' => $contentid));
+        $DB->delete_records('h5p', ['id' => $contentid]);
 
         // Remove content library dependencies.
         $this->deleteLibraryUsage($contentid);

h5p/classes/helper.php

@@ -314,18 +314,20 @@ public static function get_cache_buster(): string {
     /**
      * Get the settings needed by the H5P library.
      *
+     * @param string|null $component
      * @return array The settings.
      */
-    public static function get_core_settings(): array {
+    public static function get_core_settings(?string $component = null): array {
         global $CFG, $USER;
 
         $basepath = $CFG->wwwroot . '/';
         $systemcontext = context_system::instance();
 
-        // Generate AJAX paths.
-        $ajaxpaths = [];
-        $ajaxpaths['xAPIResult'] = '';
-        $ajaxpaths['contentUserData'] = '';
+        // H5P doesn't currently support xAPI State. It implements a mechanism in contentUserDataAjax() in h5p.js to update user
+        // data. However, in our case, we're overriding this method to call the xAPI State web services.
+        $ajaxpaths = [
+            'contentUserData' => '',
+        ];
 
         $factory = new factory();
         $core = $factory->get_core();
@@ -336,13 +338,17 @@ public static function get_core_settings(): array {
             $usersettings['name'] = $USER->username;
             $usersettings['id'] = $USER->id;
         }
+        $savefreq = false;
+        if ($component !== null && get_config($component, 'enablesavestate')) {
+            $savefreq = get_config($component, 'savestatefreq');
+        }
         $settings = array(
             'baseUrl' => $basepath,
             'url' => "{$basepath}pluginfile.php/{$systemcontext->instanceid}/core_h5p",
             'urlLibraries' => "{$basepath}pluginfile.php/{$systemcontext->id}/core_h5p/libraries",
             'postUserStatistics' => false,
             'ajax' => $ajaxpaths,
-            'saveFreq' => false,
+            'saveFreq' => $savefreq,
             'siteUrl' => $CFG->wwwroot,
             'l10n' => array('H5P' => $core->getLocalization()),
             'user' => $usersettings,
@@ -360,13 +366,14 @@ public static function get_core_settings(): array {
     /**
      * Get the core H5P assets, including all core H5P JavaScript and CSS.
      *
+     * @param string|null $component
      * @return Array core H5P assets.
      */
-    public static function get_core_assets(): array {
-        global $CFG, $PAGE;
+    public static function get_core_assets(?string $component = null): array {
+        global $PAGE;
 
         // Get core settings.
-        $settings = self::get_core_settings();
+        $settings = self::get_core_settings($component);
         $settings['core'] = [
             'styles' => [],
             'scripts' => []

h5p/classes/player.php

@@ -27,7 +27,11 @@
 defined('MOODLE_INTERNAL') || die();
 
 use core_h5p\local\library\autoloader;
+use core_xapi\handler;
+use core_xapi\local\state;
 use core_xapi\local\statement\item_activity;
+use core_xapi\local\statement\item_agent;
+use core_xapi\xapi_exception;
 
 /**
  * H5P player class, for displaying any local H5P content.
@@ -102,7 +106,7 @@ class player {
      * Inits the H5P player for rendering the content.
      *
      * @param string $url Local URL of the H5P file to display.
-     * @param stdClass $config Configuration for H5P buttons.
+     * @param \stdClass $config Configuration for H5P buttons.
      * @param bool $preventredirect Set to true in scripts that can not redirect (CLI, RSS feeds, etc.), throws exceptions
      * @param string $component optional moodle component to sent xAPI tracking
      * @param bool $skipcapcheck Whether capabilities should be checked or not to get the pluginfile URL because sometimes they
@@ -207,7 +211,7 @@ public function get_messages(): \stdClass {
      * main H5P config variable.
      */
     public function add_assets_to_page() {
-        global $PAGE;
+        global $PAGE, $USER;
 
         $cid = $this->get_cid();
         $systemcontext = \context_system::instance();
@@ -219,6 +223,7 @@ public function add_assets_to_page() {
             \core_h5p\file_storage::CONTENT_FILEAREA, $this->h5pid, null, null);
         $exporturl = $this->get_export_settings($displayoptions[ core::DISPLAY_OPTION_DOWNLOAD ]);
         $xapiobject = item_activity::create_from_id($this->context->id);
+
         $contentsettings = [
             'library'         => core::libraryToString($this->content['library']),
             'fullScreen'      => $this->content['library']['fullscreen'],
@@ -231,7 +236,7 @@ public function add_assets_to_page() {
             'url'             => $xapiobject->get_data()->id,
             'contentUrl'      => $contenturl->out(),
             'metadata'        => $this->content['metadata'],
-            'contentUserData' => [0 => ['state' => '{}']]
+            'contentUserData' => [0 => ['state' => $this->get_state_data($xapiobject)]],
         ];
         // Get the core H5P assets, needed by the H5P classes to render the H5P content.
         $settings = $this->get_assets();
@@ -241,6 +246,62 @@ public function add_assets_to_page() {
         $PAGE->requires->data_for_js('H5PIntegration', $settings, true);
     }
 
+    /**
+     * Get the stored xAPI state to use as user data.
+     *
+     * @param item_activity $xapiobject
+     * @return string The state data to pass to the player frontend
+     */
+    private function get_state_data(item_activity $xapiobject): string {
+        global $USER;
+
+        // Initialize the H5P content with the saved state (if it's enabled and the user has some stored state).
+        $emptystatedata = '{}';
+        $savestate = (bool) get_config($this->component, 'enablesavestate');
+        if (!$savestate) {
+            return $emptystatedata;
+        }
+
+        $xapihandler = handler::create($this->component);
+        if (!$xapihandler) {
+            return $emptystatedata;
+        }
+
+        // The component implements the xAPI handler, so the state can be loaded.
+        $state = new state(
+            item_agent::create_from_user($USER),
+            $xapiobject,
+            'state',
+            null,
+            null
+        );
+        try {
+            $state = $xapihandler->load_state($state);
+            if (!$state) {
+                return $emptystatedata;
+            }
+
+            if (is_null($state->get_state_data())) {
+                // The state content should be reset because, for instance, the content has changed.
+                return 'RESET';
+            }
+
+            $statedata = $state->jsonSerialize();
+            if (is_null($statedata)) {
+                return $emptystatedata;
+            }
+
+            if (property_exists($statedata, 'h5p')) {
+                // As the H5P state doesn't always use JSON, we have added this h5p object to jsonize it.
+                return $statedata->h5p;
+            }
+        } catch (xapi_exception $exception) {
+            return $emptystatedata;
+        }
+
+        return $emptystatedata;
+    }
+
     /**
      * Outputs H5P wrapper HTML.
      *
@@ -371,7 +432,7 @@ private function get_cid(): string {
      */
     private function get_assets(): array {
         // Get core assets.
-        $settings = helper::get_core_assets();
+        $settings = helper::get_core_assets($this->component);
         // Added here because in the helper we don't have the h5p content id.
         $settings['moodleLibraryPaths'] = $this->core->get_dependency_roots($this->h5pid);
         // Add also the Moodle component where the results will be tracked.

h5p/h5plib/v124/joubel/core/js/h5p.js

@@ -2344,6 +2344,11 @@ H5P.createTitle = function (rawTitle, maxLength) {
       done('Not signed in.');
       return;
     }
+    // Moodle patch to let override this method.
+    if (H5P.contentUserDataAjax !== undefined) {
+      return H5P.contentUserDataAjax(contentId, dataType, subContentId, done, data, preload, invalidate, async);
+    }
+    // End of Moodle patch.
 
     var options = {
       url: H5PIntegration.ajax.contentUserData.replace(':contentId', contentId).replace(':dataType', dataType).replace(':subContentId', subContentId ? subContentId : 0),