container-server/services/mail/docker-compose.yml

version: '3.7'

# https://hub.docker.com/r/mailserver/docker-mailserver
# https://docker-mailserver.github.io/docker-mailserver/edge/examples/tutorials/basic-installation/
# https://github.com/docker-mailserver/docker-mailserver
# https://github.com/docker-mailserver/docker-mailserver/blob/master/docs/content/config/advanced/mail-sieve.md
# https://docker-mailserver.github.io/docker-mailserver/latest/faq/#how-can-i-make-spamassassin-better-recognize-spam
# https://docker-mailserver.github.io/docker-mailserver/latest/examples/use-cases/imap-folders/#mailboxes-aka-imap-folders
# https://doc.dovecot.org/configuration_manual/namespace/#core_setting-namespace/mailbox/autoexpunge
# https://notes.sagredo.eu/en/qmail-notes-185/expunging-expired-junk-and-trash-emails-with-dovecot-124.html

# create account: task srv:mail-setup -- email add <user>@<domain>

networks:
  mail:
    name: mail

services:
  mail:
    image: mailserver/docker-mailserver:13
    container_name: mail
    restart: "${RESTART:-no}"
    hostname: post
    domainname: ${BASE_DOMAIN}
    cap_add:
      - NET_ADMIN # For Fail2Ban to work
    environment:
      - SSL_TYPE=letsencrypt
      # You may want to enable this: https://docker-mailserver.github.io/docker-mailserver/edge/config/environment/#spoof_protection
      # See step 8 below, which demonstrates setup with enabled/disabled SPOOF_PROTECTION:
      - SPOOF_PROTECTION=0
      # Allow sending emails from other docker containers
      # Beware creating an Open Relay: https://docker-mailserver.github.io/docker-mailserver/edge/config/environment/#permit_docker
      - PERMIT_DOCKER=connected-networks
      - ONE_DIR=1

      - ENABLE_AMAVIS=1
      - ENABLE_POSTGREY=0
      - ENABLE_CLAMAV=0
      - ENABLE_SPAMASSASSIN=1
      - ENABLE_MANAGESIEVE=1
      - ENABLE_FAIL2BAN=0

      - TZ=${TIMEZONE}
      - POSTMASTER_ADDRESS=postmaster@${BASE_DOMAIN}

      - SPAMASSASSIN_SPAM_TO_INBOX=1
      - MOVE_SPAM_TO_JUNK=1
      - SA_TAG=-10000.0   # set headers on all mails
      - SA_TAG2=3.75      # above is considered spam
      - SA_KILL=10000.0   # don't bounce/quarantine anything
      - "SA_SPAM_SUBJECT=[SPAM] "
    ports:
      - "25:25"     # SMTP  (explicit TLS => STARTTLS)
      - "143:143"   # IMAP4 (explicit TLS => STARTTLS)
      - "465:465"   # ESMTP (implicit TLS)
      - "587:587"   # ESMTP (explicit TLS => STARTTLS)
      - "993:993"   # IMAP4 (implicit TLS)
      - "4190:4190" # managesieve
    volumes:
      # config
      - ${BASE_DIR:-/srv}/mail/config:/tmp/docker-mailserver/
      - ./mail/spamassassin-learn:/etc/cron.d/spamassassin-learn:ro
      - ./mail/15-mailboxes.conf:/etc/dovecot/conf.d/15-mailboxes.conf:ro
      # Mail data
      - ${BASE_DIR:-/srv}/mail/mail-data:/var/mail/
      - ${BASE_DIR:-/srv}/mail/mail-state:/var/mail-state/
      - ${BASE_DIR:-/srv}/mail/mail-logs:/var/log/mail/
      # certificates
      - ${CERTS_DIR}/post.${BASE_DOMAIN}/post.${BASE_DOMAIN}.crt:/etc/letsencrypt/live/post.${BASE_DOMAIN}/fullchain.pem:ro
      - ${CERTS_DIR}/post.${BASE_DOMAIN}/post.${BASE_DOMAIN}.key:/etc/letsencrypt/live/post.${BASE_DOMAIN}/privkey.pem:ro
    networks:
      mail:
        aliases:
          - post.${BASE_DOMAIN}