[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
must() { "$@" || 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 "$@"
    # Version: 1.0.1
    # Input: "$@"          (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.
    #   die()            Displays message to stderr then exits with error code.
    #   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
    if [ $# -le 0 ]; then showUsage; die "FATAL:No arguments provided."; fi;
    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="$2";
                    vbm "DEBUG:Input file pathFileIn1 set to:${pathFileIn1}";
		    shift;
		else
		    die "FATAL: Specified input file does not exist:$2";
		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="$2";
                    vbm "DEBUG:Input directory pathDirIn1 set to:${pathDirIn1}";
		    shift;		    
		else # Display error if $2 is not a valid dir.
		    die "FATAL:Specified input directory does not exist:$2";
		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 $m in
				y | Y | yes) opFileOut1_overwrite="true";;
				n | N | no) opFileOut1_overwrite="false";;
				*) die "FATAL:Invalid selection.";;
			    esac
		    if [ "$opFileOut1_overwrite" == "true" ]; then
			pathFileOut1="$2";
                        vbm "DEBUG:Output file pathFileOut1 set to:${pathFileOut1}";
			shift;			
		    else
			die "FATAL:Exiting in order to not overwrite output file:${pathFileOut1}";
		    fi;
		else
		    pathFileOut1="$2";
                    vbm "DEBUG:Output file pathFileOut1 set to:${pathFileOut1}";
		    shift;		    
		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="$2";
                    vbm "DEBUG:Output directory pathDirOut1 set to:${pathDirOut1}";
		    shift;		    
		else
		    die "FATAL:Specified output directory is not valid:$2";
		fi;;
            --) # End of all options. See [2].
                shift;
                for arg in "$@"; do
                    vbm "DEBUG:adding to arrayPosArgs:$arg";
                    arrayPosArgs+=("$arg");
                done;
                break;;
            -*) showUsage; die "FATAL: Unrecognized option.";; # Display usage
	    *) showUsage; die "FATAL: Unrecognized argument.";; # 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
4a48bb01	13	must() { "$@" \|\| die "cannot $*"; } #o
2928a8e4 SBS	14	vbm() {
	15	# Description: Prints verbose message ("vbm") to stderr if opVerbose is set to "true".
	16	# Usage: vbm "DEBUG :verbose message here"
	17	# Version 0.2.0
	18	# Input: arg1: string
	19	# vars: opVerbose
	20	# Output: stderr
b64bbf81	21	# Depends: bash 5.1.16, GNU-coreutils 8.30 (echo, date)
2928a8e4 SBS	22
	23	if [ "$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 "$@"
4a48bb01	97	# Version: 1.0.1
2928a8e4 SBS	98	# Input: "$@" (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:
2928a8e4 SBS	108	# yell() Displays messages to stderr.
4a48bb01	109	# die() Displays message to stderr then exits with error code.
2928a8e4	110	# vbm() Displays messsages to stderr if opVerbose set to "true".
b64bbf81 SBS	111	# showUsage() Displays usage information about parent script.
	112	# showVersion() Displays version about parent script.
	113	# arrayPosArgs Global array for storing non-option positional arguments (i.e. arguments following the `--` option).
	114	# External dependencies: bash (5.1.16), echo
2928a8e4 SBS	115	# Ref./Attrib.:
2928a8e4 SBS	116	# [1]: Marco Aurelio (2014-05-08). "echo that outputs to stderr". https://stackoverflow.com/a/23550347
b64bbf81	117	# [2]: "Handling positional parameters" (2018-05-12). https://wiki.bash-hackers.org/scripting/posparams
2928a8e4 SBS	118
2928a8e4 SBS	119	# Initialize function
4a48bb01	120	vbm "DEBUG:processArgs function called.";
2928a8e4 SBS	121
2928a8e4 SBS	122	# Perform work
4a48bb01	123	if [ $# -le 0 ]; then showUsage; die "FATAL:No arguments provided."; fi;
2928a8e4 SBS	124	while [ ! $# -eq 0 ]; do # While number of arguments ($#) is not (!) equal to (-eq) zero (0).
	125	#yell "DEBUG:Starting processArgs while loop." # Debug stderr message. See [1].
	126	#yell "DEBUG:Provided arguments are:""$*" # Debug stderr message. See [1].
	127	case "$1" in
	128	-h \| --help) showUsage; exit 1;; # Display usage.
	129	--version) showVersion; exit 1;; # Show version
	130	-v \| --verbose) opVerbose="true"; vbm "DEBUG:Verbose mode enabled.";; # Enable verbose mode. See [1].
	131	-i \| --input-file) # Define input file path
	132	if [ -f "$2" ]; then # If $2 is file that exists, set pathFileIn1 to $2, pop $2.
	133	pathFileIn1="$2";
4a48bb01	134	vbm "DEBUG:Input file pathFileIn1 set to:${pathFileIn1}";
2928a8e4	135	shift;
2928a8e4	136	else
4a48bb01 SBS	137	die "FATAL: Specified input file does not exist:$2";
4a48bb01 SBS	138	fi;;
2928a8e4 SBS	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="$2";
4a48bb01 SBS	142	vbm "DEBUG:Input directory pathDirIn1 set to:${pathDirIn1}";
4a48bb01 SBS	143	shift;
2928a8e4	144	else # Display error if $2 is not a valid dir.
4a48bb01 SBS	145	die "FATAL:Specified input directory does not exist:$2";
4a48bb01 SBS	146	fi;;
2928a8e4 SBS	147	-o \| --output-file) # Define output file path
	148	if [ -f "$2" ]; then # If $2 is file that exists, prompt user to continue to overwrite, set pathFileOut1 to $2, pop $2.
	149	yell "Specified output file $2 already exists. Overwrite? (y/n):"
	150	read -r m; case $m in
	151	y \| Y \| yes) opFileOut1_overwrite="true";;
	152	n \| N \| no) opFileOut1_overwrite="false";;
4a48bb01	153	*) die "FATAL:Invalid selection.";;
2928a8e4 SBS	154	esac
	155	if [ "$opFileOut1_overwrite" == "true" ]; then
	156	pathFileOut1="$2";
4a48bb01 SBS	157	vbm "DEBUG:Output file pathFileOut1 set to:${pathFileOut1}";
4a48bb01 SBS	158	shift;
2928a8e4	159	else
4a48bb01 SBS	160	die "FATAL:Exiting in order to not overwrite output file:${pathFileOut1}";
4a48bb01 SBS	161	fi;
2928a8e4 SBS	162	else
2928a8e4 SBS	163	pathFileOut1="$2";
4a48bb01 SBS	164	vbm "DEBUG:Output file pathFileOut1 set to:${pathFileOut1}";
	165	shift;
	166	fi;;
2928a8e4 SBS	167	-O \| --output-dir) # Define output directory path
	168	if [ -d "$2" ]; then # If $2 is dir that exists, set pathDirOut1 to $2, pop $2
	169	pathDirOut1="$2";
4a48bb01 SBS	170	vbm "DEBUG:Output directory pathDirOut1 set to:${pathDirOut1}";
4a48bb01 SBS	171	shift;
2928a8e4	172	else
4a48bb01 SBS	173	die "FATAL:Specified output directory is not valid:$2";
4a48bb01 SBS	174	fi;;
b64bbf81 SBS	175	--) # End of all options. See [2].
	176	shift;
	177	for arg in "$@"; do
	178	vbm "DEBUG:adding to arrayPosArgs:$arg";
	179	arrayPosArgs+=("$arg");
	180	done;
	181	break;;
4a48bb01 SBS	182	-*) showUsage; die "FATAL: Unrecognized option.";; # Display usage
	183	*) showUsage; die "FATAL: Unrecognized argument.";; # Handle unrecognized options. See [1].
	184	esac;
	185	shift;
	186	done;
2928a8e4 SBS	187
2928a8e4 SBS	188	# End function
4a48bb01	189	vbm "DEBUG:processArgs function ended.";
2928a8e4 SBS	190	return 0; # Function finished.
	191	} # Evaluate script options from positional arguments (ex: $1, $2, $3, etc.).
	192
	193	#===END Declare local script functions===
	194	#==END Define script parameters==
	195
	196	#==BEGIN sample code==
	197	processArgs "$@";
	198	yell "DEBUG:Provided arguments..:""$*"
b64bbf81 SBS	199	yell "DEBUG:opVerbose...........:${opVerbose:-<unset>}";
	200	yell "DEBUG:pathDirOut1.........:${pathDirOut1:-<unset>}";
	201	yell "DEBUG:pathFileOut1........:${pathFileOut1:-<unset>}";
	202	yell "DEBUG:pathDirIn1..........:${pathDirIn1:-<unset>}";
	203	yell "DEBUG:pathFileIn1.........:${pathFileIn1:-<unset>}";
	204	yell "DEBUG:opFileOut1_overwrite:${opFileOut1_overwrite:-<unset>}";
	205	yell "DEBUG:arrayPosArgs........:$(if [[ -v arrayPosArgs ]]; then declare -p arrayPosArgs; else printf "<unset>"; fi )";
	206	#yell "DEBUG:arrayPosArgs........:${arrayPosArgs[*]}";
2928a8e4 SBS	207	#==END sample code==
	208
	209	# Author: Steven Baltaktei Sandoval
	210	# License: GPLv3+