Symfony Cache reference

In a nutshell

Symfony’s Cache component helps you implement caching in your web applications.

This is how you’d typically use the Cache component:

use Symfony\Contracts\Cache\ItemInterface;

// The callable will only be executed on a cache miss.
$value = $pool->get('my_cache_key', function (ItemInterface $item) {
    $item->expiresAfter(3600);

    // ... do some HTTP request or heavy computations
    $computedValue = 'foobar';

    return $computedValue;
});

echo $value; // 'foobar'

// ... and to remove the cache key
$pool->delete('my_cache_key');

Pools: Group of cache items

A pool is a group of cache items under a namespace. In your code, you’ll use a service to interact with each pool.

For example, you might choose to group your cache items in the following pools:

• Images: For caching files.
• Users: For caching user DB records.
• Secrets: For caching AWS secrets.

Default pools

Two pools are enabled by default:

• cache.app: Used in your application code.
• cache.system: Used for things like serializer, annotations, and validations.

These are configured in config/packages/cache.yaml:

# config/packages/cache.yaml
framework:
    cache:
        app: cache.adapter.filesystem
        system: cache.adapter.system

See all available cache pools

php bin/console cache:pool:list

Clear a pool

php bin/console cache:pool:clear my_cache_pool

Adapters

A cache adapter is a class that implements the AbstractAdapter interface allowing you to manage your caching using storage systems like Memcached or Redis.

The Cache component offers several pre-configured adapters:

• cache.adapter.apcu
• cache.adapter.array
• cache.adapter.filesystem
• cache.adapter.memcached
• cache.adapter.pdo
• cache.adapter.psr6
• cache.adapter.redis
• cache.adapter.redis_tag_aware (Redis adapter optimized to work with tags)

Sources/links

• Cache – Symfony docs
• symfony/cache GitHub repo
• CacheItemInterface