@dcl/memory-cache-component

In-memory cache component using LRU cache for local caching.

Installation

npm install @dcl/memory-cache-component

Usage

import { createInMemoryCacheComponent } from '@dcl/memory-cache-component'

const cache = createInMemoryCacheComponent()
await cache.set('key', value, 3600)
const value = await cache.get('key')

You can override the cap and the default TTL by passing an options bag:

// Larger cap, no implicit expiration (entries live until LRU evicts them).
const cache = createInMemoryCacheComponent({ max: 1_000_000, ttl: 0 })

Features

• LRU (Least Recently Used) eviction policy
• TTL support for automatic expiration
• Pattern-based key filtering
• No external dependencies (local only)
• Fast access times

Configuration

createInMemoryCacheComponent(options?) accepts:

• max — maximum number of items the cache will hold. Must be a positive integer. Defaults to 10_000.
• ttl — default TTL in milliseconds applied to every entry. Defaults to 1000 * 60 * 60 (1 hour). Pass 0 to disable TTL entirely so entries live until evicted by the LRU cap. Must not be negative.

Invalid values (non-integer or non-positive max, negative or non-finite ttl) throw a TypeError at construction time so misuse surfaces immediately.

TTL units — careful

The two ttl parameters in this API use different units:

| Where | Unit | Example | | --- | --- | --- | | createInMemoryCacheComponent({ ttl }) (constructor default) | milliseconds | ttl: 60_000 → 60 seconds | | cache.set(key, value, ttl) (per-call override) | seconds | ttl: 60 → 60 seconds | | cache.setInHash(key, field, value, ttlInSecondsForHash) | seconds | ttlInSecondsForHash: 60 → 60 seconds |

The per-call values are passed through fromSecondsToMilliseconds internally; only the constructor option is in milliseconds. Watch the unit when switching between defaults and overrides.

License

MIT