Using Redis for Queues for Multiple Laravel Applications on a Single Server

Question

I have a production laravel application and the staging application running on the same server. I am running redis, which I am using as my queue driver. They are obviously c

Answer 1

I had this same problem, and it took me hours to find the solution.

https://laravel.com/docs/5.6/queues#driver-prerequisites says:

In order to use the redis queue driver, you should configure a Redis database connection in your config/database.php configuration file.

And then https://laravel.com/docs/5.6/redis#predis says:

In addition to the default host, port, database, and password server configuration options, Predis supports additional connection parameters that may be defined for each of your Redis servers. To utilize these additional configuration options, add them to your Redis server configuration in the config/database.php configuration file.

Reading the "connection parameters" page, I eventually found https://github.com/nrk/predis/wiki/Client-Options, which says that 'prefix' is a supported option.

So, you can edit your config/database.php configuration file to have:

'redis' => [
        'client' => 'predis',
        'cluster' => false,
        'options'=>[
            'prefix' => env('REDIS_PREFIX', 'YOUR_PREFIX_HERE')
        ],
        'default' => [
            'host'     => env('REDIS_HOST', '127.0.0.1'),
            'password' => env('REDIS_PASSWORD', null),
            'port'     => env('REDIS_PORT', 6379),
            'database' => 0,
        ],
    ],

I'm not sure if you then need to restart Redis or Supervisord.

Answer 2

You can set the prefix Laravel uses for the Redis cache. By default this is laravel, so all keys are stored as laravel:keyname and Laravel takes care of the logic to add/remove this prefix when saving/getting.

You can set the prefix in config/cache.php. You could leave the main one as laravel and set your staging app prefix to stage or something. This will mean multiple Laravel apps can use the same Redis instance.

Answer 3

As of Laravel 5.5.22 the cache prefix is using the APP_NAME environment variable. You can rely on that if that's enough or alternatively you may configure the prefix by using the CACHE_PREFIX environment variable that is not set by default.

If you're using Laravel Horizon to manage your queues, you can simply override the HORIZON_PREFIX environment variable to let Horizon differentiate between your applications running side by side.