Properly use ServiceProvider extender

extensions/pusher/src/Provider/PusherProvider.php

@@ -0,0 +1,29 @@
+<?php
+
+namespace Flarum\Pusher\Provider;
+
+use Flarum\Foundation\AbstractServiceProvider;
+use Flarum\Settings\SettingsRepositoryInterface;
+
+class PusherProvider extends AbstractServiceProvider
+{
+    public function register()
+    {
+        $this->app->bind(\Pusher::class, function () {
+            $settings = $this->app->make(SettingsRepositoryInterface::class);
+
+            $options = [];
+
+            if ($cluster = $settings->get('flarum-pusher.app_cluster')) {
+                $options['cluster'] = $cluster;
+            }
+
+            return new \Pusher(
+                $settings->get('flarum-pusher.app_key'),
+                $settings->get('flarum-pusher.app_secret'),
+                $settings->get('flarum-pusher.app_id'),
+                $options
+            );
+        });
+    }
+}