MDL-46880 mod_forum: move cron to scheduled task

Note that this is a very basic conversion without doing any refactoring
to split the tasks up better. That will come in MDL-44734, this is about
being a safe backportable change to give admins better control over the
running of the forum cron task.

mod/forum/classes/task/cron_task.php

@@ -0,0 +1,48 @@
+<?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/>.
+
+/**
+ * A scheduled task for forum cron.
+ *
+ * @todo MDL-44734 This job will be split up properly.
+ *
+ * @package    mod_forum
+ * @copyright  2014 Dan Poltawski <dan@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace mod_forum\task;
+
+class cron_task extends \core\task\scheduled_task {
+
+    /**
+     * Get a descriptive name for this task (shown to admins).
+     *
+     * @return string
+     */
+    public function get_name() {
+        return get_string('crontask', 'mod_forum');
+    }
+
+    /**
+     * Run forum cron.
+     */
+    public function execute() {
+        global $CFG;
+        require_once($CFG->dirroot . '/mod/forum/lib.php');
+        forum_cron();
+    }
+
+}

mod/forum/db/tasks.php

@@ -0,0 +1,38 @@
+<?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/>.
+
+/**
+ * Definition of Forum scheduled tasks.
+ *
+ * @package   mod_forum
+ * @category  task
+ * @copyright 2014 Dan Poltawski <dan@moodle.com>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+$tasks = array(
+    array(
+        'classname' => 'mod_forum\task\cron_task',
+        'blocking' => 0,
+        'minute' => '*',
+        'hour' => '*',
+        'day' => '*',
+        'month' => '*',
+        'dayofweek' => '*'
+    )
+);

mod/forum/lang/en/forum.php

@@ -110,6 +110,7 @@
 $string['couldnotadd'] = 'Could not add your post due to an unknown error';
 $string['couldnotdeletereplies'] = 'Sorry, that cannot be deleted as people have already responded to it';
 $string['couldnotupdate'] = 'Could not update your post due to an unknown error';
+$string['crontask'] = 'Forum mailings and maintenance jobs';
 $string['delete'] = 'Delete';
 $string['deleteddiscussion'] = 'The discussion topic has been deleted';
 $string['deletedpost'] = 'The post has been deleted';

mod/forum/lib.php

@@ -434,18 +434,15 @@ function forum_cron_minimise_user_record(stdClass $user) {
 }
 
 /**
- * Function to be run periodically according to the moodle cron
+ * Function to be run periodically according to the scheduled task.
+ *
  * Finds all posts that have yet to be mailed out, and mails them
- * out to all subscribers
+ * out to all subscribers as well as other maintance tasks.
  *
- * @global object
- * @global object
- * @global object
- * @uses CONTEXT_MODULE
- * @uses CONTEXT_COURSE
- * @uses SITEID
- * @uses FORMAT_PLAIN
- * @return void
+ * NOTE: Since 2.7.2 this function is run by scheduled task rather
+ * than standard cron.
+ *
+ * @todo MDL-44734 The function will be split up into seperate tasks.
  */
 function forum_cron() {
     global $CFG, $USER, $DB;

mod/forum/version.php

@@ -24,7 +24,6 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$plugin->version   = 2014081900;       // The current module version (Date: YYYYMMDDXX)
+$plugin->version   = 2014082100;       // The current module version (Date: YYYYMMDDXX)
 $plugin->requires  = 2014050800;       // Requires this Moodle version
 $plugin->component = 'mod_forum';      // Full name of the plugin (used for diagnostics)
-$plugin->cron      = 60;