Never forget to run shellcheck on any bash/shell script you write.
Bash for production systems - presentation on “Survival guide for quality scripts”
YJL: bashlint and ShellCheck for checking Bash sources
dylanaraps/pure-bash-bible: 📖 A collection of pure bash alternatives to external processes.
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Minimal safe Bash script template | Better Dev
#!/usr/bin/env bash
set -Eeuo pipefail
cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1
trap cleanup SIGINT SIGTERM ERR EXIT
usage() {
cat <<EOF
Usage: $(basename "$0") [-h] [-v] [-f] -p param_value arg1 [arg2...]
Script description here.
Available options:
-h, --help Print this help and exit
-v, --verbose Print script debug info
-f, --flag Some flag description
-p, --param Some param description
EOF
exit
}
cleanup() {
trap - SIGINT SIGTERM ERR EXIT
# script cleanup here
}
setup_colors() {
if [[ -t 2 ]] && [[ -z "${NO_COLOR-}" ]] && [[ "${TERM-}" != "dumb" ]]; then
NOCOLOR='\033[0m' RED='\033[0;31m' GREEN='\033[0;32m' ORANGE='\033[0;33m' BLUE='\033[0;34m' PURPLE='\033[0;35m' CYAN='\033[0;36m' YELLOW='\033[1;33m'
else
NOCOLOR='' RED='' GREEN='' ORANGE='' BLUE='' PURPLE='' CYAN='' YELLOW=''
fi
}
msg() {
echo >&2 -e "${1-}"
}
die() {
local msg=$1
local code=${2-1} # default exit status 1
msg "$msg"
exit "$code"
}
parse_params() {
# default values of variables set from params
flag=0
param=''
while :; do
case "${1-}" in
-h | --help)
usage
;;
-v | --verbose)
set -x
;;
--no-color)
NO_COLOR=1
;;
-f | --flag) # example flag
flag=1
;;
-p | --param) # example named parameter
param="${2-}"
shift
;;
-?*)
die "Unknown option: $1"
;;
*)
break
;;
esac
shift
done
args=("$@")
# check required params and arguments
[[ -z "${param-}" ]] && die "Missing required parameter: param"
[[ ${#args[@]} -eq 0 ]] && die "Missing script arguments"
return 0
}
parse_params "$@"
setup_colors
# script logic here
msg "${RED}Read parameters:${NOCOLOR}"
msg "- flag: ${flag}"
msg "- param: ${param}"
msg "- arguments: ${args[*]-}"
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