* sf -- script framework #+begin_center #+caption: Logo [[./images/logo.png]] #+end_center /script framework/ can be used to simplify and beautify bash scripts. It provides: - Argument parsing - Usage output - Input functions - Output functions - Text formatting variables All just by declaring some variables and sourcing it. Or keep your scripts self-contained and include it as an oneliner. The usage is pretty self-explanatory once you have seen it. If you're curious and don't want to read through the documentation, head directly to the [[#examples][examples]]. ----- Here is the oneliner version of /sf/ which was created with [[https://github.com/precious/bash_minifier][this]] tool: #+begin_src sh # sf -- script framework (https://github.com/Deleh/sf) sftrs=$'\e[0m';sftbf=$'\e[1m';sftdim=$'\e[2m';sftul=$'\e[4m';sftblk=$'\e[5m';sftinv=$'\e[7m';sfthd=$'\e[8m';sftclr=$'\e[1A\e[K';sftk=$'\e[30m';sftr=$'\e[31m';sftg=$'\e[32m';sfty=$'\e[33m';sftb=$'\e[34m';sftm=$'\e[35m';sftc=$'\e[36m';sftw=$'\e[97m';function sferr { echo "${sftbf}${sftr}ERROR${sftrs} $1";[ -z "$2" ]&&exit 1;};function sfwarn { echo "${sftbf}${sfty}WARNING${sftrs} $1";};function sfask { if [ "$2" == "" ];then read -p "$1? [${sftbf}Y${sftrs}/${sftbf}n${sftrs}] " sfin;[[ "$sfin" =~ y|Y|^$ ]]&&sfin=true||sfin=false;else read -p "$1? [${sftbf}y${sftrs}/${sftbf}N${sftrs}] " sfin;[[ "$sfin" =~ n|N|^$ ]]&&sfin=false||sfin=true;fi;};function sfget { [ "$2" != "" ]&&read -p "$1 [${sftbf}$2${sftrs}]: " sfin||read -p "$1: " sfin;[ "$sfin" == "" ]&&[ "$2" != "" ]&&sfin="$2";};function _sferr { echo "${sftbf}${sftr}SF PARSE ERROR${sftrs} $1";exit 1;};OLDIFS=$IFS;IFS=";";_sfphead="";_sfpdesc="";_sfodesc="";_sfexamples="";_sfpargs=();declare -A _sfflags;declare -A _sfargs;for a in "${sfargs[@]}";do _sfsubst=${a//";"};_sfcount="$(((${#a} - ${#_sfsubst})))";if [ $_sfcount -eq 1 ];then read -r -a _sfparsearr<<<"${a}";_sfpargs+=("${_sfparsearr[0]}");_sfphead="$_sfphead ${_sfparsearr[0]}";_sfpdesc="$_sfpdesc ${_sfparsearr[0]};${_sfparsearr[1]}\n";elif [ $_sfcount -eq 2 ];then read -r -a _sfparsearr<<<"${a}";_sfflags["-${_sfparsearr[1]}"]="${_sfparsearr[0]}";_sfflags["--${_sfparsearr[0]}"]="${_sfparsearr[0]}";declare ${_sfparsearr[0]}=false;_sfodesc="$_sfodesc -${_sfparsearr[1]}, --${_sfparsearr[0]};${_sfparsearr[2]}\n";elif [ $_sfcount -eq 4 ];then read -r -a _sfparsearr<<<"${a}";_sfargs["-${_sfparsearr[1]}"]="${_sfparsearr[0]}";_sfargs["--${_sfparsearr[0]}"]="${_sfparsearr[0]}";declare ${_sfparsearr[0]}="${_sfparsearr[3]}";_sfodesc="$_sfodesc -${_sfparsearr[1]}, --${_sfparsearr[0]} ${_sfparsearr[2]};${_sfparsearr[4]} (default: ${_sfparsearr[3]})\n";else _sferr "Wrong argument declaration: $a";fi;done;[ "$sfparr" == true ]&&[ "${#_sfpargs[@]}" == 0 ]&&_sferr "At least one positional argument must be used with 'sfparr'";for e in "${sfexamples[@]}";do _sfsubst=${e//";"};_sfcount="$(((${#e} - ${#_sfsubst})))";if [ $_sfcount -eq 1 ];then read -r -a _sfparsearr<<<"${e}";_sfexamples="$_sfexamples ${_sfparsearr[0]};${_sfparsearr[1]}\n";else _sferr "Wrong example declaration: $e";fi;done;IFS=$OLDIFS;function _sfusage { echo -n "Usage: $(basename $0)";[ "$_sfodesc" != "" ]&&echo -n " [OPTIONS]";echo -ne "$_sfphead";[ "$sfparr" == true ]&&echo -n " ...";echo;[ ! -z ${sfdesc+x} ]&&echo -e "\n$sfdesc";if [ "$_sfpdesc" != "" ];then echo -e "\nPOSITIONAL ARGUMENTS";echo -e "$_sfpdesc"|column -c 80 -s ";" -t -W 2;fi;if [ "$_sfodesc" != "" ];then echo -e "\nOPTIONS";echo -e "$_sfodesc"|column -c 80 -s ";" -t -W 2;fi;if [ "$_sfexamples" != "" ];then echo -e "\nEXAMPLES";echo -e "$_sfexamples"|column -c 80 -s ";" -t -W 2;fi;if [ ! -z ${sfextra+x} ];then echo -e "\n$sfextra";fi;exit 0;};for a in "$@";do [ "$a" == "-h" ]||[ "$a" == "--help" ]&&_sfusage;done;while(("$#"));do if [ ! -z ${_sfflags["$1"]} ];then declare ${_sfflags["$1"]}=true;elif [ ! -z ${_sfargs["$1"]} ];then if [ -n "$2" ]&&[ "${2:0:1}" != "-" ];then declare ${_sfargs["$1"]}="$2";shift;else sferr "Argument for '$1' missing";fi;else if [ "${1:0:1}" == "-" ];then sferr "Unsupported argument: $1";else if [ "${#_sfpargs[@]}" != 0 ];then declare ${_sfpargs[0]}="$1";[ "$sfparr" == true ]&&_sfplast="${_sfpargs[0]}"&&_sfparr=("$1");_sfpargs=("${_sfpargs[@]:1}");elif [ "$sfparr" == true ];then _sfparr+=("$1");else sferr "Too many positional arguments";fi;fi;fi;shift;done;[ "$sfparr" == true ]&&[ "${#_sfparr[@]}" -ge 1 ]&&read -r -a ${_sfplast}<<<"${_sfparr[@]}";if [ "$sfparr" != true ]&&[ ${#_sfpargs[@]} != 0 ];then for p in "${_sfpargs[@]}";do sferr "Positional argument '$p' missing" 0;done;exit 1;fi;unset a e _sfargs _sferr _sfexamples _sfflags _sfodesc _sfpargs _sfparr _sfpdesc _sfphead _sfplast _sfusage #+end_src ** Requirements - At least *Bash 4.x* ** Usage The general usage for writing a script with /sf/ is: 1. Declare /sf/-variables at the top of your script 2. Include /sf/ 3. Write your script with already parsed arguments, input functions, output functions and text formatting variables *** 1. /sf/-variables This is the list of variables which can be set *before* including /sf/. Everything is optional. | Name | Description | Example | |--------------+-----------------------------------------------------------------------------------------------------+----------------------------------------| | =sfdesc= | Description of the script | ~ sfdesc="This script does nothing." ~ | | =sfargs= | Array for declaration of arguments, positional arguments and flags. Look below for more information | See [[#sfargs][below]] | | =sfparr= | Flag which indicates if the last declared positional argument should be treated as array | ~ sfparr=true ~ | | =sfexamples= | Array for declaration of examples for the usage output. Look below for more information | See also [[#sfexamples][below]] | | =sfextra= | Additional usage output | ~ sfextra="No copyright." ~ | Examples which show the usage of all variables can be found [[#examples][below]] and in the =examples= directory. **** =sfargs= :properties: :custom_id: sfargs :end: This is an array of strings. Every string defines an argument, a flag or an positional argument of the script. The type is defined by the amount of semicolons in the string. | Type | Declaration order | Example | |---------------------+-----------------------------------------------------------------+---------------------------------------------------------| | Positional argument | =;= | ~sfargs+=("FILE;File to read")~ | | Flag | =;;= | ~sfargs+=("verbose;v;Enable verbose output")~ | | Argument | =;;;;= | ~sfargs+=("text;t;TEXT;done;Print TEXT when finished")~ | The order of declaration defines the order in the usage output. **** =sfexamples= :properties: :custom_id: sfexamples :end: This is also an array of strings. Examples are of the form =;= and can be added to /sf/ like this: : sfexamples+=("count 8;Count to eight") *** 2. Include /sf/ Grab the =sf= file from the repo, place it next to your script and source it with #+begin_src sh source "$(dirname $0)/sf" #+end_src *Or* just copy and paste the oneliner from above. *** 3. Write your script /sf/ deals with missing inputs and handles the parsing of arguments. This means that after /sf/ was included *you can be sure that all variables have assigned values*. Flags are either =false= or =true=, arguments have a provided value or the default value and positional arguments have a provided value. The values are stored in variables with the name =$=. If you declared for example a flag like this: #+begin_src sh sfargs+=("verbose;v;Enable verbose output") #+end_src Then the variable =$verbose= exists with a value of either =false= or =true=. **** Input functions User input can be requested with two functions. After calling a function, the user input is provided in the variable =$sfin=. | =sfask= | Takes a string as input and asks for /yes/ or /no/. If an additional argument is provided (doesn't matter what), /no/ will be default. =$sfin= is either =true= or =false= | | =sfget= | Takes a string as input and asks for user input. If a second argument is provided, this will be the default if no user input was entered | Here is a small snippet to show the usage: #+begin_src bash sfget "Please enter your name" "John" echo "Hello $sfin" sfask "Do you want to proceed" if [ "$sfin" == true ]; then sfask "Are you sure" "no" [ "$sfin" == true ] && echo "Please continue..." || echo "Bye" else echo "Bye" fi #+end_src And the execution: #+begin_example Please enter your name [John]: Jane Hello Jane! Do you want to proceed? [Y/n] Are you sure? [y/N] y Please continue... #+end_example *Note* that the colon and question marks get added by the functions. **** Output functions Two output functions are provided which can be used to throw warnings and errors. | =sfwarn= | Takes a string as input and prints a warning | | =sferr= | Takes a string as input, prints an error and exits with code 1. If an additional argument is passed (doesn't matter what), it will just throw an error and don't exit | **** Text formatting variables The following text formatting variables can be used to modify the output: | =sftrs= | Reset formatting | | =sftbf= | Bold | | =sftdim= | Dim | | =sftul= | Underline | | =sftblk= | Blinking | | =sftinv= | Invert foreground/background | | =sfthd= | Hidden | | =sftclr= | Clear the previous line | | =sftk= | Black | | =sftr= | Red | | =sftg= | Green | | =sfty= | Yellow | | =sftb= | Blue | | =sftm= | Magenta | | =sftc= | Cyan | | =sftw= | White | The variables can be used directly in =echo=, no =-e= needed. To echo the word "framework" bold and red use the variables for example like this: #+begin_src sh echo "${sftbf}${sftr}framework${sftrs}" #+end_src ** Examples :properties: :custom_id: examples :end: All examples can also be found in the =examples= directory. Play around with the /sf/-variables and see what happens. *** Count This example script counts from/to a number: #+begin_src sh #!/usr/bin/env bash # ---------------------- # sf -- script framework # ---------------------- # Declare sf variables sfdesc="A simple counter." sfargs+=("N;Number to count") sfargs+=("reverse;r;Count reverse") sfargs+=("text;t;TEXT;done;Print TEXT when finished counting") sfexamples+=("count 8;Count to eight") sfexamples+=("count -r -t go 3;Count reverse from 3 and print 'go'") sfextra="No copyright at all." # Include sf, this could be replaced with a long oneliner source "$(dirname $0)/sf" # ---------------------- # Actual script # ---------------------- if [ "$N" -ge 11 ]; then # Use parsed positional argument sferr "I can only count to/from 10" # Throw an error and exit fi counter="$N" # Use parsed positional argument echo -n "$sftbf" # Print everyting from here bold while [ "$counter" -ge 1 ]; do if [ "$reverse" == true ]; then # Use parsed flag echo " $counter" else echo " $(expr $N - $counter + 1)" # Use parsed positional argument fi counter=$(expr $counter - 1) sleep 1 done echo -n "$sftrs" # Reset text formatting echo "$text" # Use parsed argument #+end_src The usage output of the counter script is: #+begin_example Usage: count [OPTIONS] N A simple counter. POSITIONAL ARGUMENTS N Number to count OPTIONS -r, --reverse Count reverse -t, --text TEXT Print TEXT when finished counting (default: done) EXAMPLES count 8 Count to eight count -r -t go 3 Count reverse from 3 and print 'go' No copyright at all. #+end_example *** Add This script adds numbers and shows the usage of =sfparr=: #+begin_src sh #!/usr/bin/env bash # ---------------------- # sf -- script framework # ---------------------- # Declare sf variables sfdesc="Calculate the sum of multiple numbers." sfargs+=("NUMBERS;Numbers which will be added") sfargs+=("verbose;v;Enable verbose output") sfparr=true # Treat the last declared positional argument as array # Include sf, this could be replaced with a long oneliner source "$(dirname $0)/sf" # ---------------------- # Actual script # ---------------------- sum=0 for n in "${NUMBERS[@]}"; do # Use parsed positional argument array if [ "$verbose" == true ]; then # Use parsed flag echo -n "$sum + $n = " fi sum="$(expr $sum + $n)" if [ "$verbose" == true ]; then # Use parsed flag echo "$sftbf$sum$sftrs" # Use text formatting variables fi done echo "The sum is: $sftbf$sum$sftrs" # Use text formatting variables #+end_src And here is the produced usage: #+begin_example Usage: add [OPTIONS] NUMBERS ... Calculate the sum of multiple numbers. POSITIONAL ARGUMENTS NUMBERS Numbers which will be added OPTIONS -v, --verbose Enable verbose output #+end_example