Processing command line options with multiple arguments in Bash [duplicate] - bash

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Storing bash script argument with multiple values
(1 answer)
Closed 5 years ago.
I have been researching on using bash scripts to process command-line arguments. I have multiple optional arguments, each of which have one or more operands. An example is:
./script.sh -f file1 file2 -s server1 server2
-f itself is optional, but must be followed by filename; -s is optional, can be used without any operands or operands.
I know I can force putting "" on operands so I only deal with arguments with one operand and can use case $1 $2 shift to process it.
But I am interested in doing so without quotes, just to save some typing for the users.
A rough idea would be read in "$#" as one string, and separate them by space, then locate arguments with -/-- and assign operands following them. Maybe I can use an array to do that?
Any suggestions would be welcome.

Answer 1

Thanks folks for your wonderful suggestions. After spending some more time I resolved to the solution below:
Simply put, I use case and few checks to determine if the argument is an option or not. I use only alter flag variables during argument processing and then use the flags to determine what functions I will perform. In a way that I can have options in different order.
main(){
# flags, 1 is false, 0 is true. it's the damn bash LOCAL_DEPLOY=1
SERVER_DEPLOY=1 DRY_RUN=0
FILES=("${ALLOWEDFILES[#]}");
DEPLOYTARGET=("${ALLOWEDSERVERS[#]}");
if [ $# -eq 0 ]
then
printf -- "Missing optins, perform DRY RUN\nFor help, run with -h/--help\n"
for target in "${FILES[#]}"; do generate "$target"; done
echo "....dry run: markdown files generated in rendered/"
exit 0
fi
while true ; do
case "$1" in
-f |--file) # required operands
case "$2" in
"") die $1 ;;
*)
FILES=($2)
for i in "${FILES[#]}"; do
if is_option $i; then die $1; fi # check for option
if ! check_allowed $i ${ALLOWEDFILES[#]}; then exit 1; fi
done;
shift 2;; # input FILES are good
esac ;;
-l|--local) # no operands expected
DRY_RUN=1 # turn off dryrun
LOCAL_DEPLOY=0 # turn on local deploy
shift ;;
-s|--server) # optional operands
case "$2" in
"") shift ;;
*)
DEPLOYTARGET=($2) # use input
for i in "${DEPLOYTARGET[#]}"; do
if is_option $i; then die $1; fi # check for option
if ! check_allowed $i ${ALLOWEDSERVERS[#]}; then exit 1; fi
done ; shift 2;; # use input value
esac
DRY_RUN=1
SERVER_DEPLOY=0
;;
-n|--dryrun) # dry-run:generate markdown files only
DRY_RUN=0
shift ;;
-h|--help) # docs
print_help
exit 0
;;
--) shift; break ;;
-?*)
printf 'ERROR: Unkown option: %s\nExisting\n\n' "$1" >&2
print_help
exit 1
shift
;;
*)
break ;;
esac
done
echo "choose files: ${FILES[#]}"
echo ""
# dry-run
if [ $DRY_RUN == 0 ]; then
echo "..perform dry run.."
for target in "${FILES[#]}"; do generate "$target"; done
echo "....dry run: markdown files generated in rendered/"
exit 0
fi
# local-deploy
if [ $LOCAL_DEPLOY == 0 ] && [ $SERVER_DEPLOY != 0 ]; then
echo "..deploy locally"
for target in "${FILES[#]}"; do
generate "$target" > /dev/null
deploylocal "$target"
done;
# sync hexo-gcs hexo-yby
cd "$(dirname $HEXOLOCATION)"
./syncRepo.sh
printf -- "....hexo-gcs hexo-yby synced\n"
cd $CURRENTLOCATION
fi
# server-deploy
if [ $SERVER_DEPLOY == 0 ]; then
echo "..deploy on servers: ${DEPLOYTARGET[#]}"
echo ""
for target in "${FILES[#]}"; do # deploy locally
generate "$target" > /dev/null
deploylocal "$target"
done
# sync hexo-gcs hexo-yby
cd "$(dirname $HEXOLOCATION)"
./syncRepo.sh
printf -- "....hexo-gcs hexo-yby synced\n"
cd $CURRENTLOCATION
# deploy to selected server: git or gcp
for dt in "${DEPLOYTARGET[#]}"; do
deployserver $dt
done
fi
}