ref

Secrets

Secrets in Docker Compose

add secret to postgres

echo "your_password" | docker secret create pg_pass_secret -

version: '3.1'
services:
  postgres:
    image: postgres
    environment:
      POSTGRES_PASSWORD_FILE: /run/secrets/postgres_password_secret
    secrets:
      - postgres_password_secret
secrets:
  postgres_password_secret:
    external: true