@courseproof/cache

In-memory caching layer for certificate verification results. Uses LRU eviction with TTL support to avoid redundant network requests.

Exports

MemoryCacheBackend

In-memory Map-based implementation of the CacheBackend interface with automatic TTL eviction and configurable max entries.

| Method | Description | |--------|-------------| | get(key) | Retrieves a cached value (returns undefined if expired or missing) | | set(key, value, ttlMs) | Stores a value with a TTL in milliseconds | | delete(key) | Removes a key from cache | | clear() | Empties the entire cache | | has(key) | Checks if a key exists and is not expired | | size | Returns the number of cached entries |

CertificateCache

Higher-level cache wrapping a CacheBackend with convenience methods for verification results.

| Method | Description | |--------|-------------| | getVerification(url) | Retrieves a cached CertificateResult | | setVerification(url, value) | Caches a CertificateResult (default TTL: 1 hour) | | hasVerification(url) | Checks if a URL has a cached result | | invalidate(url) | Removes a cached verification | | clear() | Empties the entire cache |

CacheOptions

| Option | Default | Description | |--------|---------|-------------| | defaultTtlMs | 3_600_000 (1 hour) | Default TTL for cached entries | | maxEntries | 1000 | Maximum number of entries before LRU eviction | | backend | MemoryCacheBackend | Custom CacheBackend implementation |

Usage

import { CertificateCache } from "@courseproof/cache";

const cache = new CertificateCache({ defaultTtlMs: 30 * 60 * 1000 }); // 30 min

// Store verification result
await cache.setVerification("https://coursera.org/verify/abc123", result);

// Retrieve cached result
const cached = await cache.getVerification("https://coursera.org/verify/abc123");

// Check without retrieving
const exists = await cache.hasVerification("https://coursera.org/verify/abc123");

Installation

npm install @courseproof/cache

License

MIT — see LICENSE for details.

Part of the CourseProof monorepo.