[BK-2020-03.git] / unitproc / bkt-processArgs

#!/bin/bash
# Desc: Processes script arguments

#==BEGIN Define script parameters==
#===BEGIN Define variables===
:
declare -ag arrayPosArgs
#===END Define variables===

#===BEGIN Declare local script functions===
yell() { echo "$0: $*" >&2; }      #o Yell, Die, Try Three-Fingered Claw technique
die() { yell "$*"; exit 111; }     #o Ref/Attrib: https://stackoverflow.com/a/25515370
try() { "$@" || die "cannot $*"; } #o
vbm() {
    # Description: Prints verbose message ("vbm") to stderr if opVerbose is set to "true".
    # Usage: vbm "DEBUG :verbose message here"
    # Version 0.2.0
    # Input: arg1: string
    #        vars: opVerbose
    # Output: stderr
    # Depends: bash 5.1.16, GNU-coreutils 8.30 (echo, date)

    if [ "$opVerbose" = "true" ]; then
	functionTime="$(date --iso-8601=ns)"; # Save current time in nano seconds.
	echo "[$functionTime]:$0:""$*" 1>&2;  # Display argument text.
    fi

    # End function
    return 0; # Function finished.
} # Displays message if opVerbose true
showUsage() {
    # Desc: Display script usage information
    # Usage: showUsage
    # Version 0.0.2
    # Input: none
    # Output: stdout
    # Depends: GNU-coreutils 8.30 (cat)
    cat <<'EOF'
    USAGE:
        bktemp-processArgs [ options ] [FILE...]

    OPTIONS:
        -h, --help
                Display help information.
        --version
                Display script version.
        -v, --verbose
                Display debugging info.
        -i, --input-file
                Define input file path.
        -I, --input-dir
                Define input directory path.
        -o, --output-file
                Define output file path.
        -O, --output-dir
                Define output directory path.
        --
                Indicate end of options.

    EXAMPLE:
      bktemp-processArgs -o foo.txt
      bktemp-processArgs -o foo.txt -- some_file.txt
EOF
} # Display information on how to use this script.
showVersion() {
    # Desc: Displays script version and license information.
    # Usage: showVersion
    # Version: 0.0.2
    # Input: scriptVersion   var containing version string
    # Output: stdout
    # Depends: vbm(), yell, GNU-coreutils 8.30

    # Initialize function
    vbm "DEBUG:showVersion function called."

    cat <<'EOF'
bktemp-processArgs 1.0.0
Copyright (C) 2021 Steven Baltakatei Sandoval
License GPLv3: GNU GPL version 3
This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

    GNU Coreutils 8.32
    Copyright (C) 2020 Free Software Foundation, Inc.
    License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
    This is free software: you are free to change and redistribute it.
    There is NO WARRANTY, to the extent permitted by law.
EOF
    
    # End function
    vbm "DEBUG:showVersion function ended."
    return 0; # Function finished.
} # Display script version.
processArgs() {
    # Desc: Processes arguments provided to script.
    # Usage: processArgs "$@"
    # Version: 1.0.0
    # Input: "$@"          (list of arguments provided to the function)
    # Output: Sets following variables used by other functions:
    #   opVerbose            Indicates verbose mode enable status.  (ex: "true", "false")
    #   pathDirOut1          Path to output directory.
    #   pathFileOut1         Path to output file.
    #   pathDirIn1           Path to input directory.
    #   pathFileIn1          Path to input file.
    #   opFileOut1_overwrite Indicates whether file pathFileOut1 should be overwritten (ex: "true", "false").
    #   arrayPosArgs         Array of remaining positional argments
    # Depends:
    #   yell()           Displays messages to stderr.
    #   vbm()            Displays messsages to stderr if opVerbose set to "true".
    #   showUsage()      Displays usage information about parent script.
    #   showVersion()    Displays version about parent script.
    #   arrayPosArgs     Global array for storing non-option positional arguments (i.e. arguments following the `--` option).
    # External dependencies: bash (5.1.16), echo
    # Ref./Attrib.:
    #  [1]: Marco Aurelio (2014-05-08). "echo that outputs to stderr". https://stackoverflow.com/a/23550347
    #  [2]: "Handling positional parameters" (2018-05-12). https://wiki.bash-hackers.org/scripting/posparams

    # Initialize function
    vbm "DEBUG:processArgs function called."

    # Perform work
    while [ ! $# -eq 0 ]; do   # While number of arguments ($#) is not (!) equal to (-eq) zero (0).
	#yell "DEBUG:Starting processArgs while loop." # Debug stderr message. See [1].
        #yell "DEBUG:Provided arguments are:""$*"      # Debug stderr message. See [1].
	case "$1" in
	    -h | --help) showUsage; exit 1;; # Display usage.
	    --version) showVersion; exit 1;; # Show version
	    -v | --verbose) opVerbose="true"; vbm "DEBUG:Verbose mode enabled.";; # Enable verbose mode. See [1].
	    -i | --input-file) # Define input file path
		if [ -f "$2" ]; then # If $2 is file that exists, set pathFileIn1 to $2, pop $2.
		    pathFileIn1="$2";
		    shift;
		    vbm "DEBUG:Input file pathFileIn1 set to:""$2";
		else
		    yell "ERROR: Specified input file does not exist:""$2";
		    yell "Exiting.";
		    exit 1;
		fi ;; 
	    -I | --input-dir) # Define input directory path
		if [ -d "$2" ]; then # If $2 is dir that exists, set pathDirIn1 to $2, pop $2.
		    pathDirIn1="$2";
		    shift;
		    vbm "DEBUG:Input directory pathDirIn1 set to:""$2";
		else # Display error if $2 is not a valid dir.
		    yell "ERROR:Specified input directory does not exist:""$2";
		    yell "Exiting.";
		    exit 1;
		fi ;; 
	    -o | --output-file) # Define output file path
		if [ -f "$2" ]; then # If $2 is file that exists, prompt user to continue to overwrite, set pathFileOut1 to $2, pop $2.
		    yell "Specified output file $2 already exists. Overwrite? (y/n):"
		    read -r m; case $m in
				y | Y | yes) opFileOut1_overwrite="true";;
				n | N | no) opFileOut1_overwrite="false";;
				*) yell "Invalid selection. Exiting."; exit 1;;
			    esac
		    if [ "$opFileOut1_overwrite" == "true" ]; then
			pathFileOut1="$2";
			shift;
			vbm "DEBUG:Output file pathFileOut1 set to:""$2";
		    else
			yell "ERORR:Exiting in order to not overwrite output file:""$pathFileOut1";
			exit 1;
		    fi
		else
		    pathFileOut1="$2";
		    shift;
		    vbm "DEBUG:Output file pathFileOut1 set to:""$2";
		fi ;;
	    -O | --output-dir) # Define output directory path
		if [ -d "$2" ]; then # If $2 is dir that exists, set pathDirOut1 to $2, pop $2
		    pathDirOut1="$2";
		    shift;
		    vbm "DEBUG:Output directory pathDirOut1 set to:""$2";
		else
		    yell "ERROR:Specified output directory is not valid:""$2";
		    yell "Exiting.";
		    exit 1;
		fi ;;
            --) # End of all options. See [2].
                shift;
                for arg in "$@"; do
                    vbm "DEBUG:adding to arrayPosArgs:$arg";
                    arrayPosArgs+=("$arg");
                done;
                break;;
            -*) showUsage; yell "ERROR: Unrecognized option."; exit 1;; # Display usage
	    *) showUsage; yell "ERROR: Unrecognized argument."; exit 1;; # Handle unrecognized options. See [1].
	esac
	shift
    done

    # End function
    vbm "DEBUG:processArgs function ended."
    return  0; # Function finished.
} # Evaluate script options from positional arguments (ex: $1, $2, $3, etc.).

#===END Declare local script functions===
#==END Define script parameters==

#==BEGIN sample code==
processArgs "$@";
yell "DEBUG:Provided arguments..:""$*" 
yell "DEBUG:opVerbose...........:${opVerbose:-<unset>}";
yell "DEBUG:pathDirOut1.........:${pathDirOut1:-<unset>}";
yell "DEBUG:pathFileOut1........:${pathFileOut1:-<unset>}";
yell "DEBUG:pathDirIn1..........:${pathDirIn1:-<unset>}";
yell "DEBUG:pathFileIn1.........:${pathFileIn1:-<unset>}";
yell "DEBUG:opFileOut1_overwrite:${opFileOut1_overwrite:-<unset>}";
yell "DEBUG:arrayPosArgs........:$(if [[ -v arrayPosArgs ]]; then declare -p arrayPosArgs; else printf "<unset>"; fi )";
#yell "DEBUG:arrayPosArgs........:${arrayPosArgs[*]}";
#==END sample code==

# Author: Steven Baltaktei Sandoval
# License: GPLv3+
Commit	Line	Data
2928a8e4 SBS	1	#!/bin/bash
	2	# Desc: Processes script arguments
	3
	4	#==BEGIN Define script parameters==
	5	#===BEGIN Define variables===
	6	:
b64bbf81	7	declare -ag arrayPosArgs
2928a8e4 SBS	8	#===END Define variables===
	9
	10	#===BEGIN Declare local script functions===
	11	yell() { echo "$0: $*" >&2; } #o Yell, Die, Try Three-Fingered Claw technique
	12	die() { yell "$*"; exit 111; } #o Ref/Attrib: https://stackoverflow.com/a/25515370
	13	try() { "$@" \|\| die "cannot $*"; } #o
	14	vbm() {
	15	# Description: Prints verbose message ("vbm") to stderr if opVerbose is set to "true".
	16	# Usage: vbm "DEBUG :verbose message here"
	17	# Version 0.2.0
	18	# Input: arg1: string
	19	# vars: opVerbose
	20	# Output: stderr
b64bbf81	21	# Depends: bash 5.1.16, GNU-coreutils 8.30 (echo, date)
2928a8e4 SBS	22
	23	if [ "$opVerbose" = "true" ]; then
	24	functionTime="$(date --iso-8601=ns)"; # Save current time in nano seconds.
	25	echo "[$functionTime]:$0:""$*" 1>&2; # Display argument text.
	26	fi
	27
	28	# End function
	29	return 0; # Function finished.
	30	} # Displays message if opVerbose true
	31	showUsage() {
	32	# Desc: Display script usage information
	33	# Usage: showUsage
b64bbf81	34	# Version 0.0.2
2928a8e4 SBS	35	# Input: none
	36	# Output: stdout
	37	# Depends: GNU-coreutils 8.30 (cat)
	38	cat <<'EOF'
	39	USAGE:
	40	bktemp-processArgs [ options ] [FILE...]
	41
	42	OPTIONS:
	43	-h, --help
	44	Display help information.
	45	--version
	46	Display script version.
	47	-v, --verbose
	48	Display debugging info.
	49	-i, --input-file
	50	Define input file path.
	51	-I, --input-dir
	52	Define input directory path.
	53	-o, --output-file
b64bbf81	54	Define output file path.
2928a8e4	55	-O, --output-dir
b64bbf81 SBS	56	Define output directory path.
	57	--
	58	Indicate end of options.
2928a8e4 SBS	59
	60	EXAMPLE:
	61	bktemp-processArgs -o foo.txt
b64bbf81	62	bktemp-processArgs -o foo.txt -- some_file.txt
2928a8e4 SBS	63	EOF
	64	} # Display information on how to use this script.
	65	showVersion() {
	66	# Desc: Displays script version and license information.
	67	# Usage: showVersion
b64bbf81	68	# Version: 0.0.2
2928a8e4 SBS	69	# Input: scriptVersion var containing version string
	70	# Output: stdout
	71	# Depends: vbm(), yell, GNU-coreutils 8.30
	72
	73	# Initialize function
	74	vbm "DEBUG:showVersion function called."
	75
	76	cat <<'EOF'
b64bbf81	77	bktemp-processArgs 1.0.0
2928a8e4 SBS	78	Copyright (C) 2021 Steven Baltakatei Sandoval
	79	License GPLv3: GNU GPL version 3
	80	This is free software; you are free to change and redistribute it.
	81	There is NO WARRANTY, to the extent permitted by law.
	82
b64bbf81 SBS	83	GNU Coreutils 8.32
b64bbf81 SBS	84	Copyright (C) 2020 Free Software Foundation, Inc.
2928a8e4 SBS	85	License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
	86	This is free software: you are free to change and redistribute it.
	87	There is NO WARRANTY, to the extent permitted by law.
	88	EOF
	89
	90	# End function
	91	vbm "DEBUG:showVersion function ended."
	92	return 0; # Function finished.
	93	} # Display script version.
	94	processArgs() {
	95	# Desc: Processes arguments provided to script.
	96	# Usage: processArgs "$@"
b64bbf81	97	# Version: 1.0.0
2928a8e4 SBS	98	# Input: "$@" (list of arguments provided to the function)
	99	# Output: Sets following variables used by other functions:
	100	# opVerbose Indicates verbose mode enable status. (ex: "true", "false")
	101	# pathDirOut1 Path to output directory.
	102	# pathFileOut1 Path to output file.
	103	# pathDirIn1 Path to input directory.
	104	# pathFileIn1 Path to input file.
b64bbf81 SBS	105	# opFileOut1_overwrite Indicates whether file pathFileOut1 should be overwritten (ex: "true", "false").
b64bbf81 SBS	106	# arrayPosArgs Array of remaining positional argments
2928a8e4 SBS	107	# Depends:
	108	# yell() Displays messages to stderr.
	109	# vbm() Displays messsages to stderr if opVerbose set to "true".
b64bbf81 SBS	110	# showUsage() Displays usage information about parent script.
	111	# showVersion() Displays version about parent script.
	112	# arrayPosArgs Global array for storing non-option positional arguments (i.e. arguments following the `--` option).
	113	# External dependencies: bash (5.1.16), echo
2928a8e4 SBS	114	# Ref./Attrib.:
2928a8e4 SBS	115	# [1]: Marco Aurelio (2014-05-08). "echo that outputs to stderr". https://stackoverflow.com/a/23550347
b64bbf81	116	# [2]: "Handling positional parameters" (2018-05-12). https://wiki.bash-hackers.org/scripting/posparams
2928a8e4 SBS	117
	118	# Initialize function
	119	vbm "DEBUG:processArgs function called."
	120
	121	# Perform work
	122	while [ ! $# -eq 0 ]; do # While number of arguments ($#) is not (!) equal to (-eq) zero (0).
	123	#yell "DEBUG:Starting processArgs while loop." # Debug stderr message. See [1].
	124	#yell "DEBUG:Provided arguments are:""$*" # Debug stderr message. See [1].
	125	case "$1" in
	126	-h \| --help) showUsage; exit 1;; # Display usage.
	127	--version) showVersion; exit 1;; # Show version
	128	-v \| --verbose) opVerbose="true"; vbm "DEBUG:Verbose mode enabled.";; # Enable verbose mode. See [1].
	129	-i \| --input-file) # Define input file path
	130	if [ -f "$2" ]; then # If $2 is file that exists, set pathFileIn1 to $2, pop $2.
	131	pathFileIn1="$2";
	132	shift;
	133	vbm "DEBUG:Input file pathFileIn1 set to:""$2";
	134	else
	135	yell "ERROR: Specified input file does not exist:""$2";
	136	yell "Exiting.";
	137	exit 1;
	138	fi ;;
	139	-I \| --input-dir) # Define input directory path
	140	if [ -d "$2" ]; then # If $2 is dir that exists, set pathDirIn1 to $2, pop $2.
	141	pathDirIn1="$2";
	142	shift;
	143	vbm "DEBUG:Input directory pathDirIn1 set to:""$2";
	144	else # Display error if $2 is not a valid dir.
	145	yell "ERROR:Specified input directory does not exist:""$2";
	146	yell "Exiting.";
	147	exit 1;
	148	fi ;;
	149	-o \| --output-file) # Define output file path
	150	if [ -f "$2" ]; then # If $2 is file that exists, prompt user to continue to overwrite, set pathFileOut1 to $2, pop $2.
	151	yell "Specified output file $2 already exists. Overwrite? (y/n):"
	152	read -r m; case $m in
	153	y \| Y \| yes) opFileOut1_overwrite="true";;
	154	n \| N \| no) opFileOut1_overwrite="false";;
	155	*) yell "Invalid selection. Exiting."; exit 1;;
	156	esac
	157	if [ "$opFileOut1_overwrite" == "true" ]; then
	158	pathFileOut1="$2";
	159	shift;
	160	vbm "DEBUG:Output file pathFileOut1 set to:""$2";
	161	else
	162	yell "ERORR:Exiting in order to not overwrite output file:""$pathFileOut1";
	163	exit 1;
	164	fi
	165	else
	166	pathFileOut1="$2";
	167	shift;
	168	vbm "DEBUG:Output file pathFileOut1 set to:""$2";
	169	fi ;;
	170	-O \| --output-dir) # Define output directory path
	171	if [ -d "$2" ]; then # If $2 is dir that exists, set pathDirOut1 to $2, pop $2
	172	pathDirOut1="$2";
	173	shift;
	174	vbm "DEBUG:Output directory pathDirOut1 set to:""$2";
	175	else
	176	yell "ERROR:Specified output directory is not valid:""$2";
	177	yell "Exiting.";
	178	exit 1;
b64bbf81 SBS	179	fi ;;
	180	--) # End of all options. See [2].
	181	shift;
	182	for arg in "$@"; do
	183	vbm "DEBUG:adding to arrayPosArgs:$arg";
	184	arrayPosArgs+=("$arg");
	185	done;
	186	break;;
	187	-*) showUsage; yell "ERROR: Unrecognized option."; exit 1;; # Display usage
	188	*) showUsage; yell "ERROR: Unrecognized argument."; exit 1;; # Handle unrecognized options. See [1].
2928a8e4 SBS	189	esac
	190	shift
	191	done
	192
	193	# End function
	194	vbm "DEBUG:processArgs function ended."
	195	return 0; # Function finished.
	196	} # Evaluate script options from positional arguments (ex: $1, $2, $3, etc.).
	197
	198	#===END Declare local script functions===
	199	#==END Define script parameters==
	200
	201	#==BEGIN sample code==
	202	processArgs "$@";
	203	yell "DEBUG:Provided arguments..:""$*"
b64bbf81 SBS	204	yell "DEBUG:opVerbose...........:${opVerbose:-<unset>}";
	205	yell "DEBUG:pathDirOut1.........:${pathDirOut1:-<unset>}";
	206	yell "DEBUG:pathFileOut1........:${pathFileOut1:-<unset>}";
	207	yell "DEBUG:pathDirIn1..........:${pathDirIn1:-<unset>}";
	208	yell "DEBUG:pathFileIn1.........:${pathFileIn1:-<unset>}";
	209	yell "DEBUG:opFileOut1_overwrite:${opFileOut1_overwrite:-<unset>}";
	210	yell "DEBUG:arrayPosArgs........:$(if [[ -v arrayPosArgs ]]; then declare -p arrayPosArgs; else printf "<unset>"; fi )";
	211	#yell "DEBUG:arrayPosArgs........:${arrayPosArgs[*]}";
2928a8e4 SBS	212	#==END sample code==
	213
	214	# Author: Steven Baltaktei Sandoval
	215	# License: GPLv3+