From 927ea4eec5c7154174307aac5b6baedb40bd1d43 Mon Sep 17 00:00:00 2001
From: Sami Mazouz <sychocouldy@gmail.com>
Date: Tue, 19 Jan 2021 20:40:19 +0100
Subject: [PATCH] Add Notification extender beforeSending method (#2533)

---
 src/Extend/Notification.php                   | 18 +++++++
 src/Notification/NotificationSyncer.php       | 17 ++++++
 .../extenders/NotificationTest.php            | 52 +++++++++++++++++--
 3 files changed, 83 insertions(+), 4 deletions(-)

diff --git a/src/Extend/Notification.php b/src/Extend/Notification.php
index fd0f59a1b..1a6a9cbfa 100644
--- a/src/Extend/Notification.php
+++ b/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 @@ class Notification implements ExtenderInterface
         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 @@ class Notification implements ExtenderInterface
         $container->extend('flarum.notification.drivers', function ($existingDrivers) {
             return array_merge($existingDrivers, $this->drivers);
         });
+
+        foreach ($this->beforeSendingCallbacks as $callback) {
+            NotificationSyncer::beforeSending(ContainerUtil::wrapCallback($callback, $container));
+        }
     }
 }
diff --git a/src/Notification/NotificationSyncer.php b/src/Notification/NotificationSyncer.php
index b6c40ead2..7e7a5c4ff 100644
--- a/src/Notification/NotificationSyncer.php
+++ b/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 @@ class NotificationSyncer
             $this->setDeleted($toUndelete, false);
         }
 
+        foreach (static::$beforeSendingCallbacks as $callback) {
+            $newRecipients = $callback($blueprint, $newRecipients);
+        }
+
         // Create a notification record, and send an email, for all users
         // receiving this notification for the first time (we know because they
         // didn't have a record in the database). As both operations can be
@@ -176,4 +185,12 @@ class NotificationSyncer
     {
         return static::$notificationDrivers;
     }
+
+    /**
+     * @param callable|string $callback
+     */
+    public static function beforeSending($callback): void
+    {
+        static::$beforeSendingCallbacks[] = $callback;
+    }
 }
diff --git a/tests/integration/extenders/NotificationTest.php b/tests/integration/extenders/NotificationTest.php
index 2fd8ad46f..5f3aea281 100644
--- a/tests/integration/extenders/NotificationTest.php
+++ b/tests/integration/extenders/NotificationTest.php
@@ -14,10 +14,14 @@ use Flarum\Notification\Blueprint\BlueprintInterface;
 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 @@ class NotificationTest extends TestCase
         $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