MDL-63120 core_badges: Avoid multiple joins in sql statement

badges/criteria/award_criteria_activity.php

@@ -236,6 +236,7 @@ class award_criteria_activity extends award_criteria {
      * @return array list($join, $where, $params)
      */
     public function get_completed_criteria_sql() {
+        global $DB;
         $join = '';
         $where = '';
         $params = array();
@@ -257,18 +258,41 @@ class award_criteria_activity extends award_criteria {
             }
             return array($join, $where, $params);
         } else {
-            foreach ($this->params as $param) {
-                $join .= " LEFT JOIN {course_modules_completion} cmc{$param['module']} ON
-                          cmc{$param['module']}.userid = u.id AND
-                          cmc{$param['module']}.coursemoduleid = :completedmodule{$param['module']} AND
-                          ( cmc{$param['module']}.completionstate = :completionpass{$param['module']} OR
-                            cmc{$param['module']}.completionstate = :completionfail{$param['module']} OR
-                            cmc{$param['module']}.completionstate = :completioncomplete{$param['module']} )";
-                $where .= " AND cmc{$param['module']}.coursemoduleid IS NOT NULL ";
-                $params["completedmodule{$param['module']}"] = $param['module'];
-                $params["completionpass{$param['module']}"] = COMPLETION_COMPLETE_PASS;
-                $params["completionfail{$param['module']}"] = COMPLETION_COMPLETE_FAIL;
-                $params["completioncomplete{$param['module']}"] = COMPLETION_COMPLETE;
+            // Get all cmids of modules related to the criteria.
+            $cmids = array_map(fn ($x) => $x['module'], $this->params);
+            list($cmcmodulessql, $paramscmc) = $DB->get_in_or_equal($cmids, SQL_PARAMS_NAMED);
+
+            // Create a sql query to get all users who have worked on these course modules.
+            $sql = "SELECT DISTINCT userid FROM {course_modules_completion} cmc "
+            . "WHERE coursemoduleid " . $cmcmodulessql . " AND "
+            . "( cmc.completionstate IN ( :completionpass, :completionfail, :completioncomplete ) )";
+            $paramscmcs = [
+                'completionpass' => COMPLETION_COMPLETE_PASS,
+                'completionfail' => COMPLETION_COMPLETE_FAIL,
+                'completioncomplete' => COMPLETION_COMPLETE
+            ];
+            $paramscmc = array_merge($paramscmc, $paramscmcs);
+            $userids = $DB->get_records_sql($sql, $paramscmc);
+
+            // Now check each user if the user has a completion of each module.
+            $useridsbadgeable = array_keys(array_filter(
+                $userids,
+                function ($user) use ($cmcmodulessql, $paramscmc, $cmids) {
+                    global $DB;
+                    $params = array_merge($paramscmc, ['userid' => $user->userid]);
+                    $select = "coursemoduleid " . $cmcmodulessql . " AND userid = :userid";
+                    $cmidsuser = $DB->get_fieldset_select('course_modules_completion', 'coursemoduleid', $select, $params);
+                    return empty(array_diff($cmidsuser, $cmids));
+                }
+            ));
+
+            // Finally create a where statement (if neccessary) with all userids who are allowed to get the badge.
+            // This list also includes all users who have previously received the badge. These are filtered out in the badge.php.
+            $join = "";
+            $where = "";
+            if (!empty($useridsbadgeable)) {
+                list($wherepart, $params) = $DB->get_in_or_equal($useridsbadgeable, SQL_PARAMS_NAMED);
+                $where = " AND u.id " . $wherepart;
             }
             return array($join, $where, $params);
         }

badges/tests/badgeslib_test.php

@@ -31,6 +31,7 @@ require_once($CFG->libdir . '/badgeslib.php');
 require_once($CFG->dirroot . '/badges/lib.php');
 
 use core_badges\helper;
+use core\task\manager;
 
 class badgeslib_test extends advanced_testcase {
     protected $badgeid;
@@ -511,6 +512,88 @@ class badgeslib_test extends advanced_testcase {
         $this->assertEquals(badge_message_from_template($message, $params), $result);
     }
 
+    /**
+     * Test for working around the 61 tables join limit of mysql in award_criteria_activity in combination with the scheduled task.
+     * @return void
+     * @throws dml_transaction_exception
+     * @throws coding_exception
+     * @throws dml_exception
+     * @throws moodle_exception
+     * @throws ddl_exception
+     * @throws AssertionFailedError
+     * @throws InvalidArgumentException
+     * @throws ExpectationFailedException
+     * @covers \core_badges\badge->review_all_criteria()
+     */
+    public function test_badge_activity_criteria_with_a_huge_number_of_coursemodules() {
+        global $CFG;
+        require_once($CFG->dirroot.'/completion/criteria/completion_criteria_activity.php');
+
+        // Messaging is not compatible with transactions.
+        $this->preventResetByRollback();
+
+        // Create more than 61 modules to potentially trigger an mysql db error.
+        $assigncount = 75;
+        $assigns = [];
+        for ($i = 1; $i <= $assigncount; $i++) {
+            $assigns[] = $this->getDataGenerator()->create_module('assign', ['course' => $this->course->id], ['completion' => 1]);
+        }
+        $assigncmids = array_flip(array_map(fn ($assign) => $assign->cmid, $assigns));
+        $criteriaactivityarray = array_fill_keys(array_keys($assigncmids), 1);
+
+        // Set completion criteria.
+        $criteriadata = (object) [
+            'id' => $this->course->id,
+            'criteria_activity' => $criteriaactivityarray,
+        ];
+        $criterion = new completion_criteria_activity();
+        $criterion->update_config($criteriadata);
+
+        $badge = new badge($this->coursebadge);
+
+        $criteriaoverall = award_criteria::build(array('criteriatype' => BADGE_CRITERIA_TYPE_OVERALL, 'badgeid' => $badge->id));
+        $criteriaoverall->save(array('agg' => BADGE_CRITERIA_AGGREGATION_ANY));
+        $criteriaactivity = award_criteria::build(['criteriatype' => BADGE_CRITERIA_TYPE_ACTIVITY, 'badgeid' => $badge->id]);
+
+        $modulescrit = ['agg' => BADGE_CRITERIA_AGGREGATION_ALL];
+        foreach ($assigns as $assign) {
+            $modulescrit['module_' . $assign->cmid] = $assign->cmid;
+        }
+        $criteriaactivity->save($modulescrit);
+
+        // Take one assign to complete it later.
+        $assingtemp = array_shift($assigns);
+
+        // Mark the user to complete the modules.
+        foreach ($assigns as $assign) {
+            $cmassign = get_coursemodule_from_id('assign', $assign->cmid);
+            $completion = new \completion_info($this->course);
+            $completion->update_state($cmassign, COMPLETION_COMPLETE, $this->user->id);
+        }
+
+        // Run the scheduled task to issue the badge. But the badge should not be issued.
+        ob_start();
+        $task = manager::get_scheduled_task('core\task\badges_cron_task');
+        $task->execute();
+        ob_end_clean();
+
+        $this->assertFalse($badge->is_issued($this->user->id));
+
+        // Now complete the last uncompleted module.
+        $cmassign = get_coursemodule_from_id('assign', $assingtemp->cmid);
+        $completion = new \completion_info($this->course);
+        $completion->update_state($cmassign, COMPLETION_COMPLETE, $this->user->id);
+
+        // Run the scheduled task to issue the badge. Now the badge schould be issued.
+        ob_start();
+        $task = manager::get_scheduled_task('core\task\badges_cron_task');
+        $task->execute();
+        ob_end_clean();
+
+        $this->assertDebuggingCalled('Error baking badge image!');
+        $this->assertTrue($badge->is_issued($this->user->id));
+    }
+
     /**
      * Test badges observer when course module completion event id fired.
      */