"Docker redis error": connect ECONNREFUSED 127.0.0.1:6379 [duplicate] - docker

Question

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Error: Redis connection to 127.0.0.1:6379 failed - connect ECONNREFUSED 127.0.0.1:6379
(7 answers)
Closed 1 year ago.
###############
Docker file
###############
FROM node:alpine
WORKDIR '/app'
COPY package.json .
RUN yarn
COPY . .
CMD ["yarn","run","start"]
###################
docker-compose.yml
###################
version: '3'
services:
redis-server:
image: 'redis'
node-app:
build: .
ports:
- "8081:8081"
---------------------------app.js---------------------------------------
const express = require('express');
const redis = require('redis');
const app = express();
const client = redis.createClient({
host:'localhost',
port: 6379
});
client.set('visits', 0);
app.get('/', (req, res) => { client.get('visits', (err, visits) => { res.send('Number of visits is ' + visits); client.set('visits', parseInt(visits) + 1); }); });
app.listen(8081, () => { console.log('Listening on port 8081'); });
##################################
Error message
##################################
node:events:346
throw er; // Unhandled 'error' event
^
Error: connect ECONNREFUSED 127.0.0.1:6379

Answer 1

As I see from app.js code, you're trying to access one docker container from another by using localhost, which is wrong. Docker-compose creates a network for your services and gives them hostname equal to service name by default. You can reference docker compose networking documentation for more details.
So, you should access redis service from your app by redis-server host instead of localhost.
Also, there is no exposed redis port in your docker-compose file. It should look like
version: '3'
services:
redis-server:
image: 'redis'
- "6379:6379"
node-app:
build: .
ports:
- "8081:8081"
And your application should create redis connection next way:
const client = redis.createClient({ host:'redis-server', port: 6379 });