I’m trying to deploy a Golang app using docker compose but unfortunately the PostgreSQL DB connection isn’t working.

Here’s my docker-compose.yml file:

services:
  db:
    image: postgres:16.3-alpine
    container_name: "backend-db"
    ports:
      - "5432:5432"
    restart: always
    environment:
      - POSTGRES_DB=${DB_NAME}
      - POSTGRES_USER=${DB_USERNAME}
      - POSTGRES_PASSWORD=${DB_PASSWORD}
    networks:
      - fullstack
    volumes:
      - database_postgres:/var/lib/postgresql/data
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U ${DB_USERNAME}"]
      interval: 3s
      timeout: 3s
      retries: 5
    expose:
      - "5432"

  api:
    build: .
    container_name: "backend-api"
    ports:
      - "4000:4000"
    depends_on:
      db:
        condition: service_healthy
    networks:
      - fullstack

volumes:
  database_postgres:
  migrations:
networks:
  fullstack:
    driver: bridge

I’m doing a docker compose up --build to test the app locally and whenever my app tries to interact with the DB, I get:

dial tcp [::1]:5432: connect: connection refused

However, if I change in the api networks: fullstack by - network_mode: "host" I get pq: SSL is not enabled on the server.

Please notice that I’m using an .env file to load the environment variables, and in my case, the variable REMOTI_DB_DSN has appended sslmode=disable but it looks like it’s not being picked up.

Thanks a lot in advance!