cacheable-middleware

1.0.0 verified Sat Apr 25 auth: no javascript

Middleware for Express/Connect to set HTTP cache headers (Cache-Control, Expires) on responses. Version 1.0.0 (latest) requires Node >=6. Methods: res.cacheFor(milliseconds) or res.cacheFor(amount, unit) using Moment.js duration syntax. Can also set default cache duration for all routes in a middleware stack. Lightweight, no dependencies beyond Node built-ins. Differs from express-cache-headers by offering both per-response and global configuration.

Common errors

error TypeError: cacheable is not a function ↓

cause Importing incorrectly (e.g., named import when using default export).

fix

Use default import: const cacheable = require('cacheable-middleware');

error Error: Cannot find module 'cacheable-middleware' ↓

cause Package not installed or typo in package name.

fix

Run npm install cacheable-middleware and verify package.json.

error TypeError: res.cacheFor is not a function ↓

cause Middleware not applied before route handler.

fix

Ensure app.use(cacheable()) is called before defining routes that use res.cacheFor().

Warnings

breaking Version 1.0.0 drops support for Node.js < 6. Requires ES6 features. ↓

fix Upgrade Node.js to version 6 or higher.

deprecated Equivalent functionality exists in HTTP framework built-in features (Express 'static' middleware cache options) and dedicated cache-control modules. ↓

fix Consider using express.static with maxAge option for static files: app.use('/static', express.static('public', { maxAge: '1d' })).

gotcha Duration units are parsed by Moment.js; invalid strings may throw or produce unexpected durations. ↓

fix Use valid Moment.js duration formats: number (milliseconds) or number + string (e.g., 6, 'months', 3, 'hours').

gotcha res.cacheFor() must be called before res.send() or res.json() to set headers properly. ↓

fix Call res.cacheFor() at the beginning of the route handler, before sending response.

Install

npm install cacheable-middleware

yarn add cacheable-middleware

pnpm add cacheable-middleware

Imports

default function

wrong

const { cacheable } = require('cacheable-middleware');

correct

import cacheable from 'cacheable-middleware';

Default export is the middleware factory function. Named export does not exist.

default (CommonJS)
wrong
```
const { cacheable } = require('cacheable-middleware');
```
correct
```
const cacheable = require('cacheable-middleware');
```
CommonJS require returns the default export as a function, not an object with named properties.
TypeScript types
```
import cacheable from 'cacheable-middleware';
```
No official TypeScript types. Use `@types/cacheable-middleware` or declare module manually.

Quickstart

Demonstrates two usage patterns: global cache duration applied to a path and per-response control via res.cacheFor().

const express = require('express');
const cacheable = require('cacheable-middleware');

const app = express();

// Set default cache to 1 hour (3600000 ms) for all /static routes
app.use('/static', cacheable(3600000));

// Per-route caching using res.cacheFor()
app.get('/dynamic', (req, res) => {
  res.cacheFor(60000); // cache for 1 minute
  res.json({ message: 'this response is cached for 1 minute' });
});

// Use Moment.js duration syntax (value, unit string)
app.get('/long', (req, res) => {
  res.cacheFor(6, 'months');
  res.send('cached for 6 months');
});

app.listen(3000);