Cache league table

Cache the league table for 12 hours in redis

index.js

@@ -3,6 +3,12 @@ const axios = require('axios');
 const redis = require('redis');
 require('dotenv').config();
 const app = express();
+const redisPort = 6379;
+const client = redis.createClient(redisPort);
+
+client.on('error', (err) => {
+  console.log(err);
+});
 
 const config = {
   headers: {
@@ -16,13 +22,31 @@ const config = {
 };
 
 app.get('/pl', async (req, res) => {
+  const league = '39';
   try {
+    client.get(league, async (err, leagueTable) => {
+      if (err) throw err;
+
+      // Return cached league table if present
+      if (leagueTable) {
+        res.status(200).send({
+          table: JSON.parse(leagueTable),
+          message: 'data retrieved from cache',
+        });
+      } else {
+        // Fetch from the API
         const leagueTable = await axios.get(
           'https://v3.football.api-sports.io/standings',
           config
         );
+        // Save result to cache
+        client.setex(league, 43200, JSON.stringify(leagueTable.data));
+        // Return data from API
         res.status(200).send({
           table: leagueTable.data,
+          message: 'cache miss',
+        });
+      }
     });
   } catch (err) {
     res.status(500).send({ message: err.message });