Allow the subscription broadcast job queue to be configured

composer.json

@@ -25,6 +25,7 @@
     "require": {
         "php": ">= 7.1",
         "ext-json": "*",
+        "illuminate/bus": "5.5.* || 5.6.* || 5.7.* || 5.8.* || ^6.0 || ^7.0",
         "illuminate/contracts": "5.5.* || 5.6.* || 5.7.* || 5.8.* || ^6.0 || ^7.0",
         "illuminate/http": "5.5.* || 5.6.* || 5.7.* || 5.8.* || ^6.0 || ^7.0",
         "illuminate/pagination": "5.5.* || 5.6.* || 5.7.* || 5.8.* || ^6.0 || ^7.0",

src/Subscriptions/Events/BroadcastSubscriptionEvent.php

@@ -3,8 +3,11 @@
 namespace Nuwave\Lighthouse\Subscriptions\Events;
 
 use Illuminate\Queue\SerializesModels;
-use Nuwave\Lighthouse\Schema\Types\GraphQLSubscription as Subscription;
+use Nuwave\Lighthouse\Schema\Types\GraphQLSubscription;
 
+/**
+ * @deprecated will be removed in v5 and replaced with a Job
+ */
 class BroadcastSubscriptionEvent
 {
     use SerializesModels;
@@ -21,7 +24,7 @@ class BroadcastSubscriptionEvent
 
     public $root;
 
-    public function __construct(Subscription $subscription, string $fieldName, $root)
+    public function __construct(GraphQLSubscription $subscription, string $fieldName, $root)
     {
         $this->subscription = $subscription;
         $this->fieldName = $fieldName;

src/Subscriptions/Events/BroadcastSubscriptionListener.php

@@ -2,19 +2,23 @@
 
 namespace Nuwave\Lighthouse\Subscriptions\Events;
 
-use Illuminate\Contracts\Queue\ShouldQueue;
-use Nuwave\Lighthouse\Subscriptions\Contracts\BroadcastsSubscriptions;
+use Illuminate\Contracts\Bus\Dispatcher as BusDispatcher;
+use Nuwave\Lighthouse\Subscriptions\Job\BroadcastSubscriptionJob;
 
-class BroadcastSubscriptionListener implements ShouldQueue
+/**
+ * @deprecated This class is just here to preserve backwards compatiblity with v4.
+ * TODO remove the event and handle subscriptions as commands only in v5
+ */
+class BroadcastSubscriptionListener
 {
     /**
-     * @var \Nuwave\Lighthouse\Subscriptions\Contracts\BroadcastsSubscriptions
+     * @var \Illuminate\Contracts\Events\Dispatcher
      */
-    protected $broadcaster;
+    protected $busDispatcher;
 
-    public function __construct(BroadcastsSubscriptions $broadcaster)
+    public function __construct(BusDispatcher $busDispatcher)
     {
-        $this->broadcaster = $broadcaster;
+        $this->busDispatcher = $busDispatcher;
     }
 
     /**
@@ -24,10 +28,12 @@ public function __construct(BroadcastsSubscriptions $broadcaster)
      */
     public function handle(BroadcastSubscriptionEvent $event): void
     {
-        $this->broadcaster->broadcast(
-            $event->subscription,
-            $event->fieldName,
-            $event->root
+        $this->busDispatcher->dispatch(
+            (new BroadcastSubscriptionJob(
+                $event->subscription,
+                $event->fieldName,
+                $event->root
+            ))->onQueue(config('lighthouse.subscriptions.broadcasts_queue_name', null))
         );
     }
 }

src/Subscriptions/Job/BroadcastSubscriptionJob.php

@@ -0,0 +1,50 @@
+<?php
+
+namespace Nuwave\Lighthouse\Subscriptions\Job;
+
+use Illuminate\Bus\Queueable;
+use Illuminate\Contracts\Queue\ShouldQueue;
+use Nuwave\Lighthouse\Schema\Types\GraphQLSubscription;
+use Nuwave\Lighthouse\Subscriptions\Contracts\BroadcastsSubscriptions;
+
+class BroadcastSubscriptionJob implements ShouldQueue
+{
+    use Queueable;
+
+    /**
+     * The subscription field that was requested.
+     *
+     * @var \Nuwave\Lighthouse\Schema\Types\GraphQLSubscription
+     */
+    public $subscription;
+
+    /**
+     * The name of the field.
+     *
+     * @var string
+     */
+    public $fieldName;
+
+    /**
+     * The root element to be passed when resolving the subscription.
+     *
+     * @var mixed
+     */
+    public $root;
+
+    public function __construct(GraphQLSubscription $subscription, string $fieldName, $root)
+    {
+        $this->subscription = $subscription;
+        $this->fieldName = $fieldName;
+        $this->root = $root;
+    }
+
+    public function handle(BroadcastsSubscriptions $broadcaster): void
+    {
+        $broadcaster->broadcast(
+            $this->subscription,
+            $this->fieldName,
+            $this->root
+        );
+    }
+}

src/Subscriptions/SubscriptionBroadcaster.php

@@ -66,6 +66,7 @@ public function __construct(
      */
     public function queueBroadcast(GraphQLSubscription $subscription, string $fieldName, $root): void
     {
+        // TODO replace with a job dispatch
         $this->eventsDispatcher->dispatch(
             new BroadcastSubscriptionEvent($subscription, $fieldName, $root)
         );

src/lighthouse.php

@@ -246,6 +246,11 @@
          */
         'queue_broadcasts' => env('LIGHTHOUSE_QUEUE_BROADCASTS', true),
 
+        /*
+         * Determines the queue to use for broadcasting queue jobs.
+         */
+        'broadcasts_queue_name' => env('LIGHTHOUSE_BROADCASTS_QUEUE_NAME', null),
+
         /*
          * Default subscription storage.
          *
@@ -254,7 +259,7 @@
         'storage' => env('LIGHTHOUSE_SUBSCRIPTION_STORAGE', 'redis'),
 
         /*
-         * Default subscription storage time to live.
+         * Default subscription storage time to live in seconds.
          *
          * Indicates how long a subscription can be active before it's automatically removed from storage.
          * Setting this to `null` means the subscriptions are stored forever. This may cause