command.md

Module - Command

Command/Function utility.

• get_option
• parse_option

get_option

################################################################################
# Simulate the function `getopt`.
#
# Usage: get_option <option_string> <args> <option_out> <param_out>
#
# Parameters:
#   option_string [in]  Option string (*).
#   args          [in]  The array of arguments.
#   option_out    [out] The array of parsed options, the result can use
#                       `parse_option` to parse.
#   param_out     [out] The array of parsed parameters.
#
# Returns:
#   ${LIB_BASH_ERROR_INVALID_PARAM}
#   ${LIB_BASH_ERROR_INVALID_OPTION}
#   ${LIB_BASH_ERROR_NO_OUTPUT}
#
# `get_option` supports '--' for indicate the end of options and long option,
# besides all whitespace inside the options and parameters are preserved.
#
# *:
# The option string is a list of option configuration with pattern `o[option]:`
#   o        The short option, this is a required field and must be an alphabet.
#   [option] The long option, this is optional and must be alphabets and '_'.
#   :        The colon indicate the option will have data to follow.
# Example:
#   ab[beta]c:d[delta]:
#   This option string indicate 4 possible options:
#     1st option - short:a long: data:no
#     2nd option - short:b long:beta data:no
#     3rd option - short:c long: data:yes
#     4th option - short:d long:delta data:yes
################################################################################

Example 1:

################################################################################
# argument.sh

#!/usr/bin/env bash

source 'command.sh'

args=("${@}")
get_option 'ab[beta]c:d[delta]:e:' args[@] options params
exit_code=${?}
if [[ ${exit_code} -ne 0 ]]; then
  exit ${exit_code}
fi

for option in "${options[@]}"; do
  parse_option "${option}" opt data
  printf "%s\n" "Option:${opt} Data:${data}"
done

for param in "${params[@]}"; do
  printf "%s\n" "Param:${param}"
done

Output:

$ ./argument.sh -a --beta -c ccc --delta=ddd -eee p1 p2
Option:a Data:
Option:b Data:
Option:c Data:ccc
Option:d Data:ddd
Option:e Data:eee
Param:p1
Param:p2

Example 2:

function argument()
{
  local args=("${@}")

  local options=()
  local params=()
  get_option 'ab[beta]c:d[delta]:e:' args[@] options params
  exit_code=${?}
  if [[ ${exit_code} -ne 0 ]]; then
    return ${exit_code}
  fi

  local option=''
  for option in "${options[@]}"; do
    local opt=''
    local data=''
    parse_option "${option}" opt data
    printf "%s\n" "Option:${opt} Data:${data}"
  done

  local param=''
  for param in "${params[@]}"; do
    printf "%s\n" "Param:${param}"
  done

  return 0
}

argument -a --beta -c ccc --delta=ddd -eeee p1 p2

Output:

Option:a Data:
Option:b Data:
Option:c Data:ccc
Option:d Data:ddd
Option:e Data:eee
Param:p1
Param:p2

parse_option

################################################################################
# Parse the option output from `get_option`.
#
# Usage: parse_option <option_result> <option_out> <data_out>
#
# Parameters:
#   option_result [in]  The option output from `get_option`
#   option_out    [out] The short option as key.
#   data_out      [out] The data from the argument.
#
# Returns:
#   ${LIB_BASH_ERROR_INVALID_PARAM}
#   ${LIB_BASH_ERROR_NO_OUTPUT}
################################################################################

Please see the example from get_option.