Simple compose file for Postgresql

docker-compose.yml

version: '3.7'

services:
  db:
    image: postgres:12.1-alpine
    ports:
      - '5432:5432'
    volumes:
      - ./data:/var/lib/postgresql/data
    environment:
      - POSTRGES_USER=postgres
      - POSTGRES_PASSWORD=123456

volumes:
  data: