Docker Compose for Stack with Secrets

docker-compose-stack-secrets.yml

version: '3.1'

services:
  drupal:
    image: drupal:8.2
    ports:
      - 80:80
    volumes: 
      - data:/var/lib/postgresql/data
      - modules:/var/www/html/modules
      - profiles:/var/www/html/profiles
      - themes:/var/www/html/themes
      - sites:/var/www/html/sites

  postgres:
    image: postgres:9.6
    secrets:
      - postgres_password
    environment: 
      POSTGRES_PASSWORD_FILE: /run/secrets/postgres_password
    volumes: 
      - drupal-data:/var/lib/postgresql/data

secrets:
  postgres_password:
    external: true      

volumes: 
  data:
  modules:
  profiles:
  themes:
  sites:
  drupal-data: