docker_system_prune.sh

#!/bin/bash
# external variable sources
  source /opt/docker/scripts/.color_codes.conf
  source /opt/docker/scripts/.vars_docker.env

# function definitions
  fnc_help(){
    echo -e "${blu:?}[-> This script prunes (removes) '${cyn:?}container${blu:?}' ${cyn:?}images${def:?}, ${cyn:?}volumes${blu:?} and ${CUR}unused${def:?} ${cyn:?}networks${blu:?} <-]${def:?} "
    echo -e " -"
    echo -e " - SYNTAX: # dprn"
    echo -e " - SYNTAX: # dprn ${cyn:?}-option${def:?}"
    echo -e " -   VALID OPTION(S):"
    echo -e " -     ${cyn:?}-a │ --all  ${def:?}│ Stops all containers then removes all '${cyn:?}container${blu:?}' ${cyn:?}images${def:?}, ${cyn:?}volumes${def:?} and ${CUR}unused${def:?} ${cyn:?}networks${def:?}"
    echo -e " -     ${cyn:?}-h │ --help ${def:?}│ Displays this help message"
    echo
    exit 1 # Exit script after printing help
    }
  fnc_intro(){ echo -e "${blu:?}[-> PRUNING THE DOCKER SYSTEM <-]${def:?}"; }
  fnc_outro(){ echo -e "${grn:?}[-- DOCKER SYSTEM PRUNE COMPLETE --]${def:?}"; echo; }
  fnc_prune(){ docker system prune --all --force --volumes; }
  fnc_container_list(){ docker container ls --all --quiet; }
  fnc_container_stop(){ docker stop $(fnc_container_list); }
  fnc_invalid_syntax(){ echo -e "${ylw:?} >> INVALID OPTION SYNTAX, USE THE -${cyn:?}help${ylw:?} OPTION TO DISPLAY PROPER SYNTAX <<${def:?}"; exit 1; }
  fnc_invalid_input(){ echo -e "${ylw:?}INVALID INPUT${def:?}: Must be any case-insensitive variation of '(Y)es' or '(N)o'."; }
  fnc_nothing_to_do(){ echo -e " - ${ylw:?}nothing to prune from the docker environment${def:?}"; }
  fnc_query_remove_all(){ echo -e "Are you sure you want to ${red:?}STOP${def:?} and ${ylw:?}REMOVE${def:?} all containers?"; }

# Script start notification
  fnc_intro

# Script logic and execution
  case "${1}" in
    (-*)
      case "${1}" in
        ("-h"|"-help"|"--help") fnc_help ;;
        ("-a"|"--all")
          if [[ "$(fnc_container_list)" ]]; then
            fnc_query_remove_all
            while read -r -p " [(Y)es/(N)o] " input; do
              case "${input}" in
                ([yY]|[yY][eE][sS]) fnc_container_stop && echo && fnc_prune && break;;
                ([nN]|[nN][oO]) break ;;
                (*) fnc_invalid_input ;;
              esac
            done
          else fnc_nothing_to_do
          fi
          ;;
        (*) fnc_invalid_syntax ;;
      esac
      ;;
    (*) fnc_prune ;;
  esac

# Script completion notice
  echo
  # fnc_outro