cal/compose.smtpauth.yml

---
version: "3.8"

services:
  app:
    environment:
      - EMAIL_SERVER_PASSWORD_FILE=/run/secrets/email_server_password
    secrets:
      - email_server_password

secrets:
  email_server_password:
    external: true
    name: ${STACK_NAME}_email_server_password_${SECRET_EMAIL_SERVER_PASSWORD_VERSION}