index.js

const express = require('express');
const axios = require('axios').default;
const { client, getAsync } = require('./redis');

const app = express();

app.get('/countries', async (request, response) => {
  try {
    const redisKey = 'COUNTRIES';
    const countries = await getAsync(redisKey);

    if (countries) {
      const data = JSON.parse(countries);
      return response.status(200).json({ countries: data });
    }

    const { data } = await axios.get('https://restcountries.eu/rest/v2/all');
    await client.set(redisKey, JSON.stringify(data));
    return response.status(200).json({ countries: data });
  } catch (error) {
    console.log(error);
    return response.status(500).json({
      status: 'error',
      error: error.message,
    });
  }
});

app.listen(3000, () => {
  console.log('server listening on port 3000');
});