A Bash script template | "[Bash scripting #1] Parsing options with getopt" (https://youtu.be/Ok9hncgOtxE) | Mindful Technology

getopt-demo

#!/usr/bin/env bash

function print_demo_msg {
  printf '\x1b[38;5;243;48;5;233m%s\x1b[49;39m\n' "$1"
  printf '%s\n' "$2" #| batcat -pl bash --color=always --theme='OneHalfDark'
}

version=0.1.0

getopt -T > /dev/null
[[ $? != 4 ]] && { printf '[%s] %s\n' "${BASH_SOURCE##*/}" 'Enhanced getopt is required to run this script.' >&2; exit 1; }

print_demo_msg 'Initial arguments' "$(printf '%q ' "$0" "$@")"

help=''

opts=$(getopt -n "${BASH_SOURCE##*/}" -o 'c,C,h,V,' -l 'color,no-color,help,version,' -- "$@")

[[ $? != 0 ]] && exit 1

print_demo_msg 'Value of opts' "$(declare -p opts)"

eval set -- "$opts"

print_demo_msg 'Arguments after eval' "$(printf '%q ' "$0" "$@")"

opt_color=1

test -f "${XDG_CONFIG_HOME:-$HOME/.config}"'/test-script/config.bash' && source "$_"

while true; do
  case $1 in
    -c | --color ) opt_color=1; shift ;;
    -C | --no-color ) opt_color=; shift ;;
    -h | --help ) printf '%s\n' "$help"; exit ;;
    -V | --version ) printf '%s\n' "$version"; exit ;;
    -- ) shift; break ;;
    * ) printf '[%s] %s\n' "${BASH_SOURCE##*/}" 'Internal error: unable to parse option `'"$1"'`.' >&2; exit 1 ;;
  esac
done

print_demo_msg 'Arguments after parsing' "$(printf '%q ' "$0" "$@")"

printf \
  ${opt_color:+'\x1b[32m'}'[%s] %s'${opt_color:+'\x1b[39m'}'\n' \
  "${BASH_SOURCE##*/}" \
  'This is a getopt demo.' >&2

script-template

#!/usr/bin/env bash

version=0.1.0

getopt -T > /dev/null
[[ $? != 4 ]] && { printf '[%s] %s\n' "${BASH_SOURCE##*/}" 'Enhanced getopt is required to run this script.' >&2; exit 1; }

help=''

opts=$(getopt -n "${BASH_SOURCE##*/}" -o 'c,C,h,V,' -l 'color,no-color,help,version,' -- "$@")

[[ $? != 0 ]] && exit 1

eval set -- "$opts"

opt_color=1

test -f "${XDG_CONFIG_HOME:-$HOME/.config}"'/test-script/config.bash' && source "$_"

while true; do
  case $1 in
    -c | --color ) opt_color=1; shift ;;
    -C | --no-color ) opt_color=; shift ;;
    -h | --help ) printf '%s\n' "$help"; exit ;;
    -V | --version ) printf '%s\n' "$version"; exit ;;
    -- ) shift; break ;;
    * ) printf '[%s] %s\n' "${BASH_SOURCE##*/}" 'Internal error: unable to parse option `'"$1"'`.' >&2; exit 1 ;;
  esac
done