Laravel Cache Refs
A Laravel Artisan command to purge cache tag refs from Redis.
Problem
Have you noticed massive Redis sets which have the key suffix standard_ref or forever_ref clogging up your cache database?
If you use Laravel's cache tag feature and are unable to routinely wipe your entire cache, you will inevitably accumulate junk in your Redis database. To make this feature work, Laravel creates Redis sets for each tag with members pointing to each key assigned to that tag.
For example, let's say you have a cache key "dog" with the tag "animal". If the "dog" Redis key expires, that key's set member remains for the "animal" tag.
Solution
This command is designed to be run on a schedule job for applications experiencing this issue. It loops through all cache refs and ensures the ref set members point to existing keys. It will remove any set members that point to non existant target keys.
Usage
Install:
composer require aprivette/laravel-cache-refs
After installing, you can run the command like so:
php artisan refs:purge
This command defaults to the cache connection. If you have another cache connection, you may specify it.
php artisan refs:purge custom_redis_connection
Caveats
This package only works with Redis stores.
Future Improvements
The key queries should probably be replaced with scans for memory conservation with larger Redis stores. I haven't run into this issue yet though.