postgres docker-compose example

docker-compose.yml

services:
  db:
    image: postgres:17.2
    command:
      - postgres
      - -c
      - config_file=/etc/postgresql/postgresql.conf
    environment:
        POSTGRES_USER: u301
        POSTGRES_DB: u301
        POSTGRES_PASSWORD_FILE: /run/secrets/db_password
    volumes:
      - ./data:/var/lib/postgresql/data:Z
      - ./wal-g:/bin/wal-g:ro
      - ./my-postgres.conf:/etc/postgresql/postgresql.conf:ro
    ports:
      - 5432:5432
    secrets:
      - db_password
    healthcheck:
      #test: pg_isready -U postgres -h localhost
      test: ["CMD-SHELL", "PGPASSWORD=$(cat /run/secrets/db_password) pg_isready -U $$POSTGRES_USER -d $$POSTGRES_DB"]
      interval: 5s
      timeout: 5s
      retries: 10
    restart: unless-stopped

secrets:
  db_password:
    file: ./db_password.txt

1. create db_password.txt and write a random strong password. you can use https://1password.com/password-generator
2. run docker run -i --rm postgres cat /usr/share/postgresql/postgresql.conf.sample > my-postgres.conf to export a postgresql.conf.sample
3. wal-g is powerful database backup tool, you can download it by wget https://github.com/wal-g/wal-g/releases/download/v3.0.5/wal-g-pg-ubuntu-24.04-amd64 -O wal-g.
   a. don't forget to run chmod +x ./wal-g