docker-compose.yml

services:
  init-container-debian:
    restart: "no"
    build:
      context: .
      dockerfile: ./Dockerfile-debian
    environment:

      # Config
      - ENTRYPOINT_XTRACE=false
      - ENTRYPOINT_INFINITE=false
    # volumes:  
    
  init-container-rhel:
    restart: "no"
    build:
      context: .
      dockerfile: ./Dockerfile-rhel
    environment:
      # Config
      - ENTRYPOINT_XTRACE=false
      - ENTRYPOINT_INFINITE=false
    # volumes:
     

docker-entrypoint.sh

#!/usr/bin/env bash

# Source: https://github.com/kronostechnologies/docker-init-entrypoint/blob/master/entrypoint.sh

set -eu


process_scripts() {
	local path=$1

	if [[ ! -d $path ]]; then
		echo "> Skipping '${path}' empty directory."
	else
		for script in $(ls $path | sort -n); do
			echo "> Running '${path}/${script}'.."
			bash "${path}/${script}"
		done
	fi
}

kill_remaining_process() {
	# Gather all PIDs except for pid 1 (entrypoint script) into a
	# space separated list, send SIGTERM and wait for those process to finish properly
	ps -e > /tmp/ps
	local PIDS=`grep -v -E "PID|\s1\s|ps" /tmp/ps | awk 'BEGIN { ORS=" " }; {print $1}'`;
	rm /tmp/ps

	if [ -n "$PIDS" ]; then
		kill -TERM $PIDS
		for PID in $PIDS; do
			while [[ -d /proc/$PID ]]; do
				sleep 0.1
			done
		done
	fi
}

finish() {
	trap "" SIGTERM SIGQUIT SIGINT
	echo '> Stopping all services..'
	process_scripts "${ENTRYPOINT_ROOT}/stop.d"
	echo '> Killing remaining process..'
	kill_remaining_process
	echo '> Shutting down now.'
}


main ()
{
  # Prepare env
  echo BOOT > /tmp/status
  ENTRYPOINT_XTRACE=${ENTRYPOINT_XTRACE:-false}
  ENTRYPOINT_INFINITE=${ENTRYPOINT_INFINITE:-false}
  if [ -z ${ENTRYPOINT_ROOT+x} ]; then
    ENTRYPOINT_ROOT="/docker-entrypoints"
  fi

  # Prepare trap exit
  trap finish SIGTERM SIGQUIT SIGINT

  [ "${ENTRYPOINT_XTRACE}" == "false" ] || set -x


  # Ensure init process has been run
  echo '> Starting init processes..'
  process_scripts "${ENTRYPOINT_ROOT}/init.d"
  echo INIT > /tmp/status

  if [[ -d "${ENTRYPOINT_ROOT}/start.d" ]]; then

    # Start all services
    echo '> Starting all services..'
    process_scripts "${ENTRYPOINT_ROOT}/start.d"
    echo '> Fully Booted.'
    echo STARTED > /tmp/status

    if [[ -n "${*}" ]]; then
      echo "> Executing \`${*}\`"
      /bin/bash -c "${*}" &
    else
      sleep infinity &
    fi
    wait $!

    finish
  else
    # No services
    if [[ "$ENTRYPOINT_INFINITE" == true ]]; then
      echo '> One shot container asked to run infinitely, sleeping..'
      sleep infinity &
      wait $!
      finish
    else
      echo '> One shot container fully terminated.'
    fi
  fi
}

main "$@"

Dockerfile-debian

# Common part
# ================
FROM debian:12 AS base

# Configuration
ENV ENTRYPOINT_INFINITE=false
ENV ENTRYPOINT_XTRACE=false
ENV ENTRYPOINT_ROOT=/docker-entrypoints

# Install dependencies
RUN apt update && apt install -y procps gettext \
    && apt clean all \
  	&& rm -rf /var/cache/apt

# Provide a simple but generic init script
COPY ./docker-entrypoint.sh /docker-entrypoint.sh
CMD ["/docker-entrypoint.sh"]

# Healthcheck
HEALTHCHECK --interval=1s --timeout=1s --retries=20 \
  CMD grep -q STARTED /tmp/status

Dockerfile-rhel

# Common part
# ================
FROM rockylinux:9.3 AS base

# Configuration
ENV ENTRYPOINT_INFINITE=false
ENV ENTRYPOINT_XTRACE=false
ENV ENTRYPOINT_ROOT=/docker-entrypoints

# Install dependencies
RUN dnf install -y procps gettext \
    && dnf clean all \
  	&& rm -rf /var/cache/yum

# Provide a simple but generic init script
COPY ./docker-entrypoint.sh /docker-entrypoint.sh
CMD ["/docker-entrypoint.sh"]

# Healthcheck
HEALTHCHECK --interval=1s --timeout=1s --retries=20 \
  CMD grep -q STARTED /tmp/status