Docker connection refused between containers - postgresql

Question

I'm using Postgres, Redis and Node.js (adding dependencies with yarn), and trying to integrate it all with a docker-compose.yml file.
I have the following docker-compose.yml:
version: '3'
services:
postgres:
image: postgres:latest
restart: unless-stopped
environment:
- POSTGRES_DB=mybase
- POSTGRES_USER=myuser
- POSTGRES_PASSWORD=mypass
redis:
image: redis:latest
restart: unless-stopped
migrate:
build: .
entrypoint: node_modules/.bin/sequelize db:migrate --config src/config/database.js --migrations-path src/database/migrations/
volumes:
- ./:/app
- /app/node_modules
depends_on:
- postgres
wavetech-be:
build:
dockerfile: Dockerfile
context: .
restart: on-failure
volumes:
- /app/node_modules
- ./:/app
environment:
- REDIS_HOST=redis
- REDIS_PORT=6379
- DB_HOST=postgres
- DB_USER=myuser
- DB_PASS=mypass
- DB_PORT=5432
- DB_NAME=mybase
depends_on:
- redis
- migrate
And the following Dockerfile:
FROM node:alpine
WORKDIR "/app"
COPY ./package.json ./
RUN apk add yarn
RUN yarn
COPY . .
CMD [ "yarn", "dev" ]
However, when I docker-compose up, I keep getting connection problems with both databases:
migrate_1 |
migrate_1 | ERROR: connect ECONNREFUSED 127.0.0.1:5432
migrate_1 |
...
wavetech-be_1 | (node:85) UnhandledPromiseRejectionWarning: Error: connect ECONNREFUSED 127.0.0.1:6379

Answer 1

The answer has two parts:
First, as pointed out by #jonrsharpe, the description of the migrate service was lacking the environment variables. So, as it is with the volumes, each service needs its own environment variables configured.
migrate:
build: .
entrypoint: node_modules/.bin/sequelize db:migrate --config src/config/database.js --migrations-path src/database/migrations/
volumes:
- ./:/app
- /app/node_modules
environment:
- DB_HOST=postgres
- DB_USER=myuser
- DB_PASS=mypass
- DB_PORT=5432
- DB_NAME=mybase
- APP_PORT=3000
depends_on:
- postgres
Second, I am using Bull to manage my Redis server. I was importing a config and passing it directly to Redis, so:
import redisConfig from '../../config/redis';
...
init() {
this.queues = Object.values(jobs).map(job => ({
bull: new BullQueue(job.key, redisConfig),
name: job.key,
handle: job.handle,
}));
}
And it turns out that Bull was trying to just use the default Redis configuration. When I passed the environment variables directly into the Bull config, it worked properly:
init() {
this.queues = Object.values(jobs).map(job => ({
bull: new BullQueue(job.key, {
redis: {
host: process.env.REDIS_HOST,
port: process.env.REDIS_PORT,
},
}),
name: job.key,
handle: job.handle,
}));
}