src/Subscriptions/StorageManager.php
public function subscriberByChannel(string $channel): ?Subscriber
    {
        $key = self::SUBSCRIBER_KEY.".{$channel}";

        return $this->cache->get($key);
    }
public function subscriberByChannel(string $channel): ?Subscriber
    {
        $key = self::SUBSCRIBER_KEY.".{$channel}";

        return $this->cache->get($key);
    }
public function subscriberByChannel ( string $ channel ) : ? Subscriber { $ key = self :: SUBSCRIBER_KEY . ".{$channel}" ; return $ this -> cache -> get ( $ key ) ; }
Find subscriber by channel.

@param  string  $channel
@return \Nuwave\Lighthouse\Subscriptions\Subscriber|null
Find subscriber by channel .