Add Notification extender beforeSending method

src/Extend/Notification.php

@@ -10,6 +10,8 @@
 namespace Flarum\Extend;
 
 use Flarum\Extension\Extension;
+use Flarum\Foundation\ContainerUtil;
+use Flarum\Notification\NotificationSyncer;
 use Illuminate\Contracts\Container\Container;
 
 class Notification implements ExtenderInterface
@@ -18,6 +20,7 @@ class Notification implements ExtenderInterface
     private $serializers = [];
     private $drivers = [];
     private $typesEnabledByDefault = [];
+    private $beforeSendingCallbacks = [];
 
     /**
      * @param string $blueprint The ::class attribute of the blueprint class.
@@ -51,6 +54,17 @@ public function driver(string $driverName, string $driver, array $typesEnabledBy
         return $this;
     }
 
+    /**
+     * @param callable|string $callback
+     * @return self
+     */
+    public function beforeSending($callback)
+    {
+        $this->beforeSendingCallbacks[] = $callback;
+
+        return $this;
+    }
+
     public function extend(Container $container, Extension $extension = null)
     {
         $container->extend('flarum.notification.blueprints', function ($existingBlueprints) {
@@ -74,5 +88,9 @@ public function extend(Container $container, Extension $extension = null)
         $container->extend('flarum.notification.drivers', function ($existingDrivers) {
             return array_merge($existingDrivers, $this->drivers);
         });
+
+        foreach ($this->beforeSendingCallbacks as $callback) {
+            NotificationSyncer::beforeSending(ContainerUtil::wrapCallback($callback, $container));
+        }
     }
 }

src/Notification/NotificationSyncer.php

@@ -43,6 +43,11 @@ class NotificationSyncer
      */
     protected static $notificationDrivers = [];
 
+    /**
+     * @var array
+     */
+    protected static $beforeSendingCallbacks = [];
+
     /**
      * Sync a notification so that it is visible to the specified users, and not
      * visible to anyone else. If it is being made visible for the first time,
@@ -94,6 +99,10 @@ public function sync(Blueprint\BlueprintInterface $blueprint, array $users)
             $this->setDeleted($toUndelete, false);
         }
 
+        foreach (static::$beforeSendingCallbacks as $callback) {
+            $newRecipients = $callback($blueprint, $newRecipients);
+        }
+
         // Create a notification record, and send an email, for all users
         // receiving this notification for the first time (we know because they
         // didn't have a record in the database). As both operations can be
@@ -176,4 +185,12 @@ public static function getNotificationDrivers(): array
     {
         return static::$notificationDrivers;
     }
+
+    /**
+     * @param callable|string $callback
+     */
+    public static function beforeSending($callback): void
+    {
+        static::$beforeSendingCallbacks[] = $callback;
+    }
 }

tests/integration/extenders/NotificationTest.php

@@ -14,10 +14,14 @@
 use Flarum\Notification\Driver\NotificationDriverInterface;
 use Flarum\Notification\Notification;
 use Flarum\Notification\NotificationSyncer;
+use Flarum\Tests\integration\RetrievesAuthorizedUsers;
 use Flarum\Tests\integration\TestCase;
+use Flarum\User\User;
 
 class NotificationTest extends TestCase
 {
+    use RetrievesAuthorizedUsers;
+
     /**
      * @test
      */
@@ -119,23 +123,61 @@ public function notification_driver_enabled_types_exist_if_added()
         $this->assertContains('secondCustomDriver', $blueprints[SecondCustomNotificationType::class]);
         $this->assertEmpty($blueprints[ThirdCustomNotificationType::class]);
     }
+
+    /**
+     * @test
+     */
+    public function notification_before_sending_callback_works_if_added()
+    {
+        $this->extend(
+            (new Extend\Notification)
+                ->type(CustomNotificationType::class, 'customNotificationTypeSerializer')
+                ->driver('customNotificationDriver', CustomNotificationDriver::class)
+                ->beforeSending(function ($blueprint, $users) {
+                    if ($blueprint instanceof CustomNotificationType) {
+                        unset($users[1]);
+                    }
+
+                    return $users;
+                })
+        );
+
+        $this->prepareDatabase([
+            'users' => [
+                $this->adminUser(),
+                $this->normalUser(),
+                ['id' => 3, 'username' => 'hani']
+            ],
+        ]);
+
+        $this->app();
+
+        $users = User::whereIn('id', [1, 2, 3])->get()->all();
+
+        $notificationSyncer = $this->app()->getContainer()->make(NotificationSyncer::class);
+        $notificationSyncer->sync(new CustomNotificationType(), $users);
+
+        $this->assertEquals('potato', $users[0]->username);
+        $this->assertEquals('normal', $users[1]->username);
+        $this->assertEquals('potato', $users[2]->username);
+    }
 }
 
 class CustomNotificationType implements BlueprintInterface
 {
     public function getFromUser()
     {
-        // ...
+        return null;
     }
 
     public function getSubject()
     {
-        // ...
+        return null;
     }
 
     public function getData()
     {
-        // ...
+        return [];
     }
 
     public static function getType()
@@ -169,7 +211,9 @@ class CustomNotificationDriver implements NotificationDriverInterface
 {
     public function send(BlueprintInterface $blueprint, array $users): void
     {
-        // ...
+        foreach ($users as $user) {
+            $user->username = 'potato';
+        }
     }
 
     public function registerType(string $blueprintClass, array $driversEnabledByDefault): void