Forwards Compatibililty for Eclipse Mosquitto MQTT Broker with Docker Init Containers and Docker Compose v2 include

docker-compose.mosquitto-init.yml

# Docker Init Container
# Alpine Container that changes the File Permissions and Ownership
# of the mounted configuration files
# NOTE: WILL ALWAYS BE EXECUTED BEFORE THE MAIN MOSQUITTO CONTAINER
# NOTE: WILL ALSO PERMANENTLY CHANGE THE FILE PERMISSIONS/OWNERSHIP ON HOST
services:
  mosquitto_init:
    image: docker.io/alpine:3.18
    container_name: mosquitto_init
    command: sh -c "chmod 0400 -R /config/ && chown -R 1883:1883 /config/"
    volumes:
      - ./mosquitto/mosquitto.conf:/config/mosquitto_conf
      - ./mosquitto/users:/config/mosquitto_users

docker-compose.mosquitto.yml

# Main Compose File for Mosquitto MQTT Broker
# The `mosquitto` service is dependent on the `mosquitto_init` service
# to execute correctly / completely and load the changed configuration
# files into the current container using `volumes_from`

include:
  - docker-compose.mosquitto-init.yml

services:
  mosquitto:
    image: docker.io/eclipse-mosquitto:2.0.18
    container_name: mqtt_fwd_compatible
    entrypoint: mosquitto -c /config/mosquitto_conf
    depends_on:
      mosquitto_init:
        condition: service_completed_successfully
    security_opt:
        - "no-new-privileges=true"
    volumes_from:
      - mosquitto_init
    volumes:
      - /etc/timezone:/etc/timezone:ro
      - /etc/localtime:/etc/localtime:ro

mosquitto.conf

# under mosquitto/mosquitto.conf

# EXAMPLE CONFIG FILE WITH ADAPTED PATHS/ FILES

# MQTT Port Listener
listener    1883
protocol    mqtt

# Authentication
allow_anonymous     false
password_file       /config/mosquitto_users

# Logging Configuration
log_timestamp true
log_type all