Cache

Cache

The cache module provides a simple key-value cache with optional TTL support. It is useful for storing computed results, rate limit counters, or any data that should expire. Drivers include in-memory, Redis, and edge KV stores.

Import

import { createCache } from '@loewen-digital/fullstack/cache'

Basic usage

import { createCache } from '@loewen-digital/fullstack/cache'

const cache = createCache({ driver: 'memory' })

// Store a value (optional TTL in seconds)
await cache.set('featured-posts', posts, { ttl: 300 })

// Retrieve a value
const cached = await cache.get('featured-posts')

// Check existence without retrieving
const exists = await cache.has('featured-posts') // true

// Delete a key
await cache.delete('featured-posts')

// Clear all keys
await cache.flush()

Remember pattern

The remember helper fetches from cache if available; otherwise calls the factory and stores the result:

const posts = await cache.remember('featured-posts', 300, async () => {
  return db.query.posts.findMany({ where: (p, { eq }) => eq(p.featured, true) })
})

Incrementing counters

await cache.increment('api-calls:user:42')        // 1
await cache.increment('api-calls:user:42')        // 2
await cache.increment('api-calls:user:42', 5)     // 7
await cache.decrement('api-calls:user:42')        // 6

Redis driver

const cache = createCache({
  driver: 'redis',
  redis: { url: process.env.REDIS_URL! },
})

Driver options

Driver	Description
memory	In-process Map with TTL support. Data is lost on restart.
redis	Redis-backed cache. Requires ioredis peer dependency.
kv	Cloudflare Workers KV or compatible edge KV store.

Config options

Option	Type	Default	Description
driver	'memory' | 'redis' | 'kv'	—	Cache driver
prefix	string	''	Key prefix applied to all cache entries
redis.url	string	—	Redis connection URL
redis.tls	boolean	false	Enable TLS for Redis connection