Using Redis cluster throws a null error

Reverb Version

1.0.0-beta7

Laravel Version

11.4.0

PHP Version

8.3.6

Description

I have a project that's hosted on AWS behind a load balancer that uses a Redis cluster. When trying to enable horizontal scaling and starting the reverb server, I'm getting this error:

Trying to access array offset on null at vendor/laravel/reverb/src/Servers/Reverb/Publishing/RedisPubSubProvider.php:81

protected function redisUrl(): string {
     78▕         $config = Config::get('database.redis.default');
     79▕ 
     80▕         [$host, $port, $protocol, $query] = [
  ➜  81▕             $config['host'],
     82▕             $config['port'] ?: 6379,
     83▕             'tls' === Arr::get($config, 'scheme') ? 's' : '',
     84▕             [],
     85▕         ];

Since the config uses a cluster setup (database.redis.clusters.default and database.redis.clusters.cache), the database.redis.default key doesn't exist, which is causing the null errors.

Any help/guidance on this would be appreciated!

Steps To Reproduce

.env:

REDIS_HOST=<AWS endpoint>
REDIS_PASSWORD=null
REDIS_PORT=6379
REDIS_QUEUE={default}

REVERB_APP_ID=<id>
REVERB_APP_KEY=<key>
REVERB_APP_SECRET=<secret>
REVERB_HOST=<domain>
REVERB_PORT=8080
REVERB_SCHEME=https
REVERB_SCALING_ENABLED=true

Since we use an AWS endpoint for the cluster, there is no REDIS_URL key.

config/database.php:

'redis' => [
        'client' => env('REDIS_CLIENT', 'phpredis'),

        'options' => [
            'cluster' => env('REDIS_CLUSTER', 'redis'),
        ],

        'clusters' => [
            'cache' => [
                [
                    'url' => env('REDIS_URL'), // not used
                    'host' => env('REDIS_HOST', '127.0.0.1'),
                    'password' => env('REDIS_PASSWORD', null),
                    'port' => env('REDIS_PORT', '6379'),
                    'database' => env('REDIS_CACHE_DB', '1'),
                ],
            ],
            'default' => [
                [
                    'url' => env('REDIS_URL'), // not used
                    'host' => env('REDIS_HOST', '127.0.0.1'),
                    'password' => env('REDIS_PASSWORD', null),
                    'port' => env('REDIS_PORT', '6379'),
                    'database' => env('REDIS_DB', '0'),
                ],
            ],
        ],
    ],

Run php artisan reverb:start

laravel / reverb