【Bash】コマンドやオプションなどを使用したい場合のテンプレートシェルスクリプト

template.sh

#! /bin/bash

# Command
COMMAND=$(basename ${0})
# SubCommand
SUB_COMMAND=${1}
shift

# Default
OPTION="DEFAULT"

function usage {
    cat <<EOF

Usage:
    ${COMMAND} [command] [<options>]

Command:
    command           command
    help              help

Options:
    --option -o       option

EOF
}

function command {
  echo "command "${OPTION}
}

# OPTION
while [ $# -gt 0 ];
do
  case ${1} in
    --option|-o)
      OPTION=${2}
      shift
      ;;
  esac
  shift
done

# COMMAND
case ${SUB_COMMAND} in
    help)
      usage
      shift
      ;;
    command)
      command
      shift
      ;;
    *)
      echo "[ERROR] ${COMMAND} ${SUB_COMMAND}"
      usage
      exit 1
      ;;
esac