Implement In-Memory Caching for External API Responses

const NodeCache = require('node-cache'); // npm install node-cache
const myCache = new NodeCache({ stdTTL: 300, checkperiod: 120 }); // Cache items for 5 minutes (300 seconds)

async function getCachedApiResponse(cacheKey, apiUrl, fetchOptions = {}) {
  // Try to retrieve data from cache
  const cachedData = myCache.get(cacheKey);
  if (cachedData) {
    console.log(`Cache hit for key: ${cacheKey}`);
    return cachedData;
  }

  console.log(`Cache miss for key: ${cacheKey}. Fetching from API...`);
  try {
    const response = await fetch(apiUrl, fetchOptions);
    if (!response.ok) {
      throw new Error(`HTTP error! status: ${response.status}`);
    }
    const data = await response.json();

    // Store data in cache
    myCache.set(cacheKey, data);
    console.log(`Data for key: ${cacheKey} cached.`);
    return data;
  } catch (error) {
    console.error(`Error fetching or parsing data from ${apiUrl}:`, error);
    throw error;
  }
}

// Example Usage in an Express route or service:
// const express = require('express');
// const app = express();
// const PORT = 3000;

// app.get('/products', async (req, res) => {
//   try {
//     // Use a unique cache key for this request, e.g., based on URL or query params
//     const products = await getCachedApiResponse('all_products', 'https://api.example.com/products');
//     res.json(products);
//   } catch (error) {
//     res.status(500).json({ message: 'Failed to retrieve products', error: error.message });
//   }
// });

// app.listen(PORT, () => console.log(`Server running on port ${PORT}`));