CacheLayer

CacheLayer is a standalone cache toolkit for modern PHP applications. It provides a unified API over PSR-6 and PSR-16 with local, distributed, and cloud adapters.

Project Background

CacheLayer was separated from the existing Intermix project to improve package visibility, maintenance focus, and faster feature enrichment for caching.

Features

• Unified Cache facade implementing PSR-6, PSR-16, ArrayAccess, and Countable
• Adapter support for APCu, File, PHP Files, Memcached, Redis, Valkey, Redis Cluster, PDO (SQLite default), Shared Memory, MongoDB, and ScyllaDB
• Tiered cache composition via Cache::tiered() (L1/L2/... descriptors or pool instances)
• Tagged invalidation with versioned tags: setTagged(), invalidateTag(), invalidateTags()
• Stampede-safe remember() with pluggable lock providers
• Per-adapter metrics counters and export hooks
• Payload compression controls
• Value serializer helpers for closures/resources
• Memoization helpers: memoize(), remember(), once()

Requirements

• PHP 8.3+
• Composer

Optional extensions/packages depend on adapter choice:

• ext-apcu
• ext-redis
• ext-memcached
• ext-pdo + driver (pdo_sqlite, pdo_pgsql, pdo_mysql, ...)
• ext-sysvshm
• mongodb/mongodb
• ext-cassandra

Installation

composer require infocyph/cachelayer

Usage

use Infocyph\CacheLayer\Cache\Cache;

$cache = Cache::pdo('app'); // defaults to sqlite file under sys temp cachelayer/pdo

$cache->setTagged('user:1', ['name' => 'Ada'], ['users'], 300);

$user = $cache->remember('user:1', function ($item) {
    $item->expiresAfter(300);
    return ['name' => 'Ada'];
}, tags: ['users']);

$cache->invalidateTag('users');

$metrics = $cache->exportMetrics();

Tiered Flow (L1 -> L2 -> DB)

use Infocyph\CacheLayer\Cache\Cache;

$cache = Cache::tiered([
    ['driver' => 'apcu', 'namespace' => 'app'], // L1
    ['driver' => 'valkey', 'namespace' => 'app', 'dsn' => 'valkey://127.0.0.1:6379'], // L2
], writeToL1: false); // optional L1 write-through

$value = $cache->remember('user:42', function ($item) use ($pdo) {
    $item->expiresAfter(300);

    $stmt = $pdo->prepare('SELECT payload FROM users_cache_source WHERE id = ?');
    $stmt->execute([42]);

    return $stmt->fetchColumn();
});

Request flow:

• check APCu (L1)
• check Redis/Valkey (L2)
• query DB on miss
• write L2
• optionally write L1 (controlled by writeToL1)

Security Hardening

CacheLayer includes optional payload/serialization hardening controls:

$cache
    ->configurePayloadSecurity(
        integrityKey: 'replace-with-strong-secret',
        maxPayloadBytes: 8_388_608,
    )
    ->configureSerializationSecurity(
        allowClosurePayloads: false,
        allowObjectPayloads: false,
    );

You can also set:

• CACHELAYER_PAYLOAD_INTEGRITY_KEY
• CACHELAYER_MAX_PAYLOAD_BYTES

See SECURITY.md for deployment guidance and threat model notes.

Documentation

https://docs.infocyph.com/projects/CacheLayer

Testing

composer test:code

Or run the full test pipeline:

composer test:all

Contributing

Contributions are welcome.

• Open an issue for bug reports or feature discussions
• Open a pull request with focused changes and tests
• Keep coding style and static checks passing before submitting
• Follow the Code of Conduct

License

MIT License. See LICENSE.