Express Caching Middleware

README.md

Usage

router.get('/', cacheMiddleware(60 * 60), mainController);

cacheMiddleware.js

const cache = require('memory-cache-pro');

const isProduction = process.env.NODE_ENV === 'production';

/**
 * This middleware makes caching
 *
 * @param {number} duration - Cache duration in seconds
 * @param {boolean=} cacheInDevelopment - Should it cache in development mode
 */
const cacheMiddleware = (duration, cacheInDevelopment = false) => {
  return (req, res, next) => {
    if (!isProduction && !cacheInDevelopment) {
      return next();
    }
    
    const url = req.originalUrl ?? req.url;
    const key = `__express__cache__url__${url}`;

    const cacheContent = cache.get(key);

    if (cacheContent) {
      return res.send(cacheContent);
    }

    res.sendResponse = res.send;

    res.send = (body) => {
      cache.put(key, body, duration * 1000);
      res.sendResponse(body);
    };

    next();
  };
};

module.exports = cacheMiddleware;