MDL-57730 core_calendar: Allow modules to control event visibility

By implementing the mod_{modname}_core_calendar_is_event_visible callback
a module can decide whether or not a user should see an event.

Part of MDL-55611 epic.

calendar/classes/local/event/core_container.php

@@ -74,14 +74,13 @@ class core_container {
      */
     private static function init() {
         if (empty(self::$eventfactory)) {
+            $identity = function(event_interface $event) {
+                return $event;
+            };
             self::$actionfactory = new action_factory();
             self::$actioneventfactory = new action_event_factory();
             self::$eventmapper = new event_mapper(
-                new event_factory(
+                new event_factory($identity, $identity)
-                    function(event_interface $event) {
-                        return $event;
-                    }
-                )
             );
             self::$eventfactory = new event_factory(
                 function(event_interface $event) {
@@ -96,6 +95,23 @@ class core_container {
                     );
 
                     return $action ? self::$actioneventfactory->create_instance($event, $action) : $event;
+                },
+                function(event_interface $event) {
+                    $mapper = self::$eventmapper;
+                    $eventvisible = component_callback(
+                        'mod_' . $event->get_course_module()->get('modname'),
+                        'core_calendar_is_event_visible',
+                        [
+                            $mapper->from_event_to_legacy_event($event)
+                        ]
+                    );
+
+                    // Module does not implement the callback, event should be visible.
+                    if (is_null($eventvisible)) {
+                        return true;
+                    }
+
+                    return $eventvisible ? true : false;
                 }
             );
         }

calendar/classes/local/event/factories/event_abstract_factory.php

@@ -43,9 +43,14 @@ use core_calendar\local\interfaces\event_interface;
  */
 abstract class event_abstract_factory implements event_factory_interface {
     /**
-     * @var callable $callbackapplier Function to apply component callbacks.
+     * @var callable $actioncallbackapplier Function to apply component action callbacks.
      */
-    protected $callbackapplier;
+    protected $actioncallbackapplier;
+
+    /**
+     * @var callable $visibilitycallbackapplier Function to apply component visibility callbacks.
+     */
+    protected $visibilitycallbackapplier;
 
     /**
      * Applies component actions to the event.
@@ -55,13 +60,23 @@ abstract class event_abstract_factory implements event_factory_interface {
      */
     protected abstract function apply_component_action(event_interface $event);
 
+    /**
+     * Exposes the event (or not)
+     *
+     * @param event_interface $event The event to potentially expose.
+     * @return event_interface|null The exposed event or null.
+     */
+    protected abstract function expose_event(event_interface $event);
+
     /**
      * Constructor.
      *
-     * @param callable $callbackapplier Function to apply component callbacks.
+     * @param callable $actioncallbackapplier     Function to apply component action callbacks.
+     * @param callable $visibilitycallbackapplier Function to apply component visibility callbacks.
      */
-    public function __construct(callable $callbackapplier) {
+    public function __construct(callable $actioncallbackapplier, callable $visibilitycallbackapplier) {
-        $this->callbackapplier = $callbackapplier;
+        $this->actioncallbackapplier = $actioncallbackapplier;
+        $this->visibilitycallbackapplier = $visibilitycallbackapplier;
     }
 
     public function create_instance(\stdClass $dbrow) {
@@ -108,7 +123,8 @@ abstract class event_abstract_factory implements event_factory_interface {
             });
         }
 
-        return $this->apply_component_action(
+        return $this->expose_event(
+            $this->apply_component_action(
                 new event(
                     $dbrow->id,
                     $dbrow->name,
@@ -128,6 +144,7 @@ abstract class event_abstract_factory implements event_factory_interface {
                     !empty($dbrow->visible),
                     $subscription
                 )
+            )
         );
     }
 }

calendar/classes/local/event/factories/event_factory.php

@@ -38,17 +38,25 @@ use core_calendar\local\interfaces\event_interface;
  */
 class event_factory extends event_abstract_factory {
     protected function apply_component_action(event_interface $event) {
-        if (!$event->get_course_module()) {
+        $callbackapplier = $this->actioncallbackapplier;
-            return $event;
-        }
-
-        $callbackapplier = $this->callbackapplier;
         $callbackresult = $callbackapplier($event);
 
         if (!$callbackresult instanceof event_interface) {
-            throw new invalid_callback_exception('Event factory callback applier must return an instance of action_interface');
+            throw new invalid_callback_exception(
+                'Event factory action callback applier must return an instance of event_interface');
         }
 
         return $callbackresult;
     }
+
+    protected function expose_event(event_interface $event) {
+        $callbackapplier = $this->visibilitycallbackapplier;
+        $callbackresult = $callbackapplier($event);
+
+        if (!is_bool($callbackresult)) {
+            throw new invalid_callback_exception('Event factory visibility callback applier must return true or false');
+        }
+
+        return $callbackresult === true ? $event : null;
+    }
 }

calendar/tests/core_container_test.php

@@ -62,6 +62,10 @@ class core_calendar_container_testcase extends advanced_testcase {
         $dbrow->id = $legacyevent->id;
         $event = $factory->create_instance($dbrow);
 
+        if (is_null($event)) {
+            return;
+        }
+
         $this->assertInstanceOf(event_interface::class, $event);
         $this->assertTrue($event instanceof event || $event instanceof action_event);
 

calendar/tests/event_factory_test.php

@@ -38,36 +38,98 @@ class core_calendar_event_factory_testcase extends advanced_testcase {
      * Test event class getters.
      *
      * @dataProvider create_instance_testcases()
-     * @param array $instanceparams Associative array of instance parameters.
+     * @param \stdClass $dbrow Row from the event table.
+     * @param callable  $actioncallbackapplier     Action callback applier.
+     * @param callable  $visibilitycallbackapplier Visibility callback applier.
+     * @param string    $expectedclass             Class the factory is expected to produce.
+     * @param mixed     $expectedattributevalue    Expected value of the modified attribute.
      */
     public function test_create_instance(
         $dbrow,
-        callable $callbackapplier,
+        callable $actioncallbackapplier,
+        callable $visibilitycallbackapplier,
+        $expectedclass,
         $expectedattributevalue
     ) {
         $this->resetAfterTest(true);
         $this->setAdminUser();
         $event = $this->create_event();
 
-        $factory = new event_factory($callbackapplier);
+        $factory = new event_factory($actioncallbackapplier, $visibilitycallbackapplier);
         $dbrow->id = $event->id;
         $instance = $factory->create_instance($dbrow);
 
+        if ($expectedclass) {
+            $this->assertInstanceOf($expectedclass, $instance);
+        }
+
+        if (is_null($expectedclass)) {
+            $this->assertNull($instance);
+        }
+
+        if ($expectedattributevalue) {
             $this->assertEquals($instance->testattribute, $expectedattributevalue);
         }
+    }
 
     /**
      * Test invalid callback exception.
      *
      * @expectedException \core_calendar\local\event\exceptions\invalid_callback_exception
      */
-    public function test_invalid_callback() {
+    public function test_invalid_action_callback() {
         $this->resetAfterTest(true);
         $this->setAdminUser();
         $event = $this->create_event();
-        $factory = new event_factory(function () {
+        $factory = new event_factory(
+            function () {
                 return 'hello';
-        });
+            },
+            function () {
+                return true;
+            }
+        );
+
+        $factory->create_instance(
+            (object)[
+                'id' => $event->id,
+                'name' => 'test',
+                'description' => 'Test description',
+                'format' => 2,
+                'courseid' => 1,
+                'groupid' => 1,
+                'userid' => 1,
+                'repeatid' => 1,
+                'modulename' => 'assign',
+                'instance' => 1,
+                'eventtype' => 'due',
+                'timestart' => 123456789,
+                'timeduration' => 12,
+                'timemodified' => 123456789,
+                'timesort' => 123456789,
+                'visible' => 1,
+                'subscriptionid' => 1
+            ]
+        );
+    }
+
+    /**
+     * Test invalid callback exception.
+     *
+     * @expectedException \core_calendar\local\event\exceptions\invalid_callback_exception
+     */
+    public function test_invalid_visibility_callback() {
+        $this->resetAfterTest(true);
+        $this->setAdminUser();
+        $event = $this->create_event();
+        $factory = new event_factory(
+            function ($event) {
+                return $event;
+            },
+            function () {
+                return 'asdf';
+            }
+        );
 
         $factory->create_instance(
             (object)[
@@ -94,7 +156,7 @@ class core_calendar_event_factory_testcase extends advanced_testcase {
 
     public function create_instance_testcases() {
         return [
-            'Sample event record' => [
+            'Sample event record with event exposed' => [
                 'dbrow' => (object)[
                     'name' => 'Test event',
                     'description' => 'Hello',
@@ -113,11 +175,44 @@ class core_calendar_event_factory_testcase extends advanced_testcase {
                     'visible' => true,
                     'subscriptionid' => 1
                 ],
-                'callbackapplier' => function(event_interface $event) {
+                'actioncallbackapplier' => function(event_interface $event) {
                     $event->testattribute = 'Hello';
                     return $event;
                 },
+                'visibilitycallbackapplier' => function(event_interface $event) {
+                    return true;
+                },
+                event_interface::class,
                 'Hello'
+            ],
+            'Sample event record with event hidden' => [
+                'dbrow' => (object)[
+                    'name' => 'Test event',
+                    'description' => 'Hello',
+                    'format' => 1,
+                    'courseid' => 1,
+                    'groupid' => 1,
+                    'userid' => 1,
+                    'repeatid' => null,
+                    'modulename' => 'Test module',
+                    'instance' => 1,
+                    'eventtype' => 'Due',
+                    'timestart' => 123456789,
+                    'timeduration' => 123456789,
+                    'timemodified' => 123456789,
+                    'timesort' => 123456789,
+                    'visible' => true,
+                    'subscriptionid' => 1
+                ],
+                'actioncallbackapplier' => function(event_interface $event) {
+                    $event->testattribute = 'Hello';
+                    return $event;
+                },
+                'visibilitycallbackapplier' => function(event_interface $event) {
+                    return false;
+                },
+                null,
+                null
             ]
         ];
     }