inject prefix

src/Illuminate/Broadcasting/BroadcastManager.php

@@ -229,7 +229,8 @@ protected function createPusherDriver(array $config)
     protected function createRedisDriver(array $config)
     {
         return new RedisBroadcaster(
-            $this->app->make('redis'), $config['connection'] ?? null
+            $this->app->make('redis'), $config['connection'] ?? null,
+            $this->app['config']->get('database.redis.options.prefix', '')
         );
     }
 

src/Illuminate/Broadcasting/Broadcasters/RedisBroadcaster.php

@@ -24,16 +24,25 @@ class RedisBroadcaster extends Broadcaster
      */
     protected $connection;
 
+    /**
+     * The Redis key prefix.
+     *
+     * @var string
+     */
+    protected $prefix;
+
     /**
      * Create a new broadcaster instance.
      *
      * @param  \Illuminate\Contracts\Redis\Factory  $redis
      * @param  string|null  $connection
+     * @param  string  $prefix
      * @return void
      */
-    public function __construct(Redis $redis, $connection = null)
+    public function __construct(Redis $redis, $connection = null, $prefix = '')
     {
         $this->redis = $redis;
+        $this->prefix = $prefix;
         $this->connection = $connection;
     }
 
@@ -47,8 +56,9 @@ public function __construct(Redis $redis, $connection = null)
      */
     public function auth($request)
     {
-        $channelName = str_replace(config('database.redis.options.prefix', ''), '', $request->channel_name);
-        $channelName = $this->normalizeChannelName($channelName);
+        $channelName = $this->normalizeChannelName(
+            str_replace($this->prefix, '', $request->channel_name)
+        );
 
         if ($this->isGuardedChannel($request->channel_name) &&
             ! $this->retrieveUser($request, $channelName)) {