Un modèle pour démarrer un script shell

Une manière de mettre en forme et d'automatiser les fonctions help() et usage()/synopsis() : En entête de chaque script :

#!/bin/bash
#################
#_# Usage       : {script} [-{options}] serviceName1 <serviceName2 ...>
#_# Description : Stop a service list
#_#               by first checking if the services are already started
#_# Options
#_#  -h         : Display short help (usage synopsis)
#_#  -H         : Display full help
#_#  -A         : Stop all active services
#_#  -K         : Stop all known services
#_#  -p <value> : Use <value> profile to stop a list of services
#_#  -P         : Display list all available profiles
#_# Example use : {script} accounting
#_#               {script} -p profile1
#################

# Script options
options=hHAKp:P

###############
# Description :
#   Give the name of current script without .sh extension
# Globals:
#   None
# Arguments:
#   None
# Outputs:
#   name of current script without .sh extension
# Return:
#   0
###############
name() {
  basename "$0" .sh
}

###############
# Description :
#   Print script usage text
# Globals:
#   $0
#   options = options string defined in calling script
# Arguments:
#   None
# Outputs:
#   Script usage text
# Explain:
# - Each calling script must start with a multilines comment block where
#   each line to be printed as usage text is prefixed by '#_#' mark
# - awk extract those lines from the calling script shell code
# - sed remove the '#_# ' prefix from those extracted lines (with ONE space character after the mark !)
# - If the usage text contains some {script} marks, then sed replace them by script's name without .sh suffix
# - If the usage text contains some {options} marks, then sed replace them by $options global variable value defined in calling script
# - Output the resulting lines as usage text
# Return:
#   0
###############
usage() {
  awk '/^#_# /{print}' "$0" | sed -e 's/^#_# //' -e "s/{script}/$(name)/" -e "s/{options}/${options:?}/"
}

###############
# Description :
#   Print script usage text first line
#   with spaces before : removed
# Globals:
#   usage
# Arguments:
#   None
# Outputs:
#   Script usage text first line
#   with spaces before : removed
## Return:
#   0
###############
synopsis() {
  usage | head -n 1 | sed -e 's/[[:space:]]*:/:/'
}

###############
# Description :
#   Call synopsis() or usage() & exit script,
#   if -h or -H option is used
# Globals:
#   displayHelpSynopsis
#   displayHelpFull
#   ok
# Arguments:
#   $1 = displayHelp value
# Outputs:
#   synopsis() output when -h option is used
#   usage() output when -H option is used
# Return:
#   0
###############
displayUsage() {
  ( ([[ $1 -eq ${displayHelpSynopsis:?} ]] && synopsis) || ([[ $1 -eq ${displayHelpFull:?} ]] && usage) ) &&
    exit "${ok:?}"
}

# Initial script options
ok=0
displayHelp=0
displayHelpSynopsis=1
displayHelpFull=2
displayProfiles=0
stopAllActives=0
stopAllKnown=0

# Read user options
while getopts ":$options" option; do
  case $option in
    h) displayHelp=${displayHelpSynopsis:?};;
    H) displayHelp=${displayHelpFull:?};;
    A) stopAllActives=1;;
    K) stopAllKnown=1;;
    p) setProfile "$OPTARG";;
    P) displayProfiles=1;;
    :) display error "${errorMsgMissingArgument:?}: -$OPTARG"
       exit "${errorMissingArgument:?}";;
    *) display error "${errorMsgUnknownOption:?}: -$OPTARG"
       exit "${errorUnknownOption:?}";;
  esac
done
shift $((OPTIND-1))

# Execute terminal actions
displayUsage "$displayHelp"
echo uTest
# Use test.sh -h and test.sh -H to see the difference (synopsis vs help)

Intéressant mais depuis que j'utilise Python pour faire mes scripts, je ne vois plus l'intérêt de bash. Le langage et l'écosystème me semble plus adapté à la création de commandes.

Le seul cas que je vois que justifierais encore l'usage de bash est de s'exécuter sur un serveur qui n'a pas Python.

Ok, c'était pour répondre dans le langage qui était le sujet de ce post. Maintenant pour python et gérer les options de la ligne de commande facilement, il y a click : https://pypi.org/project/click/

Pourquoi ne pas ajouter -o pipefail ? https://wizardzines.com/comics/bash-errors/

Car le script est en shell et non en bash.

● 15:37 simon@endurance ~ % echo $SHELL
/bin/zsh
● 15:37 simon@endurance ~ % set -o pipefail
● 15:37 simon@endurance ~ % bash
simon@endurance:~$ set -o pipefail
simon@endurance:~$ sh
$ set -o pipefail
sh: 1: set: Illegal option -o pipefail