api-cache-kit

A lightweight caching utility for Node.js and Express applications with memory cache, Redis support, TTL, and cache invalidation.

Installation

npm install api-cache-kit

Basic Usage

import cache from "api-cache-kit";

const users = await cache("users", () => fetchUsers(), {
  ttl: 60, // seconds
});

Features

Memory Cache

const data = await cache("key", () => expensiveOp(), { ttl: 300 });

Cache Invalidation

cache.invalidate("users");            // remove single key
cache.invalidatePattern("users:*");   // remove by pattern
cache.flush();                        // clear everything

Stale-While-Revalidate

Return stale data immediately while refreshing in the background:

const data = await cache("key", fetchData, {
  ttl: 60,
  staleWhileRevalidate: true,
});

Redis Support

import { createClient } from "redis";
const redis = createClient();

const data = await cache("key", fetchData, {
  ttl: 300,
  redis,
});

Express Middleware

Automatically cache API responses:

import express from "express";
import cache from "api-cache-kit";

const app = express();

app.get("/users", cache.middleware("users", { ttl: 60 }), (req, res) => {
  res.json([{ id: 1, name: "Alice" }]);
});

Params-Based Caching

Cache different query parameter combinations separately:

const data = await cache("search", () => api.search(q), {
  ttl: 60,
  params: { q },
});

Logging

const data = await cache("key", fetchData, {
  ttl: 60,
  log: true,
});
// HIT key
// MISS key
// SWR key (stale)

API

cache(key, callback, options?)

| Param | Type | Default | Description | | -------- | -------- | ------- | ------------------------------ | | key | string | required | Cache key | | callback | function | required | Async function to fetch data | | options | object | {} | See below |

Options

| Option | Type | Default | Description | | ------------------- | ------- | ------- | ---------------------------------------- | | ttl | number | 300 | Time-to-live in seconds | | redis | object | null | Redis client for external cache | | staleWhileRevalidate| boolean | false | Return stale, refresh in background | | log | boolean | false | Log cache hits/misses to console | | params | object | null | Query params to differentiate cache keys |

cache.invalidate(key, params?)

Remove a specific entry from the cache.

cache.invalidatePattern(pattern)

Remove all entries matching a regex or string pattern.

cache.flush()

Clear the entire memory cache.

cache.stats()

Return cache stats: { size, keys }.

cache.middleware(key, options?)

Express middleware for automatic response caching.

Test

node test.js

License

MIT