UnhandledPromiseRejectionWarning: Error: The client is closed in NodeJS and Redis

Question

I'm implementing Access Token and Refresh Token using JWT for login function in NodeJS application. I'm trying to use Redis to store the Refresh Token, but I'm getting the following code :

redis.js

const redis = require('redis');

require('dotenv').config({ path : __dirname + '/../config/env/.env' });

let redisClient;

redisClient = redis.createClient(6379, '127.0.0.1');

module.exports = redisClient;

authRoute.js

'use strict';

const JwtUtil     = require('../../middlewares/jwt-util');
const redisClient = require('../../middlewares/redis');

const authRouter = require('express').Router();

const jwt = new JwtUtil(); 

authRouter.post('/user-token/generate', (req, res, next) => {
    const accessToken = jwt.sign(req.body);

    const refreshToken = jwt.refresh();

    redisClient.set(req.body.id, refreshToken);

    res.status(200).send({
        result : 'success',
        data : {
            accessToken,
            refreshToken
        }
    });
});

module.exports = authRouter;

I have printed several logs, but it seems that redisClient.set(req.body.id, refreshToken); in authRoute.js. There seems to be an error in.

UnhandledPromiseRejectionWarning: Error: The client is closed

(node:24640) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag --unhandled-rejections=strict (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 2) (node:24640) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

Access Token and Refresh Token are issued normally. Also, the following code doesn't work. I'm not sure how I should rewrite the code. What should I do?

redisClient.on('connection', () => { 
  console.info('Redis connected!');
}

Although I'm using the Windows, I downloaded Redis, performed a ping test, and confirmed that the server is running.

Answer 1

As for now I am able to solve partially to get data, but for set data still not done for redis v4. #redis #v4 # redisv4

app.get('/data',(req,res) => {
     // check in redis first
    //console.log(">>>>url",url)
    (async () => {
        const userInput = (req.query.country).trim()
        const url = `https://en.wikipedia.org/w/api.php?action=parse&format=json&section=0&page=${userInput}`
   
        const client = createClient({
            host:'localhost',
        port:6379});
      
        client.on('error', (err) => console.log('Redis Client Error', err));
      
        await client.connect();

        const response = await  client.get(`${userInput}`)
        if(response){
            const output = JSON.parse(response);
            res.send(output)
        }
      })();

})