cs-3424: add solution to assignment 2

Summer-2024/CS-3424/Assignments/Assignment-2/src/assign2.bash

@@ -0,0 +1,131 @@
+#!/usr/bin/env bash
+
+set -eEuo pipefail
+
+SCRIPT_PATH="${BASH_SOURCE[0]}"
+SCRIPT_DIR="$(dirname "$SCRIPT_PATH")"
+
+#######################################
+# Print the given message to STDERR
+#######################################
+err() {
+	printf "%s\n" "${*}" >&2
+}
+
+#######################################
+# End the script with a non-zero exit code and the given message
+# Arguments:
+#   msg: The message to print to STDERR before exiting
+#######################################
+die() {
+	local msg="${*}"
+	err "${msg}"
+	exit 1
+}
+
+#######################################
+# Print a usage synopsis for the script to stdout
+#######################################
+usage() {
+	cat <<-__EOS__
+		Usage:
+		    ${SCRIPT_PATH} <input-files...>
+		Args:
+		    <input-files...>: One or more paths to files on the system
+		Example:
+		    ${SCRIPT_PATH} ./some/file/to/handle.txt ./another/file/to/handle.txt
+	__EOS__
+}
+
+#######################################
+# Replace all instances of <dstamp> or <date> with todays date in day/month/year
+# format in place for the given file
+# Arguments:
+#   file: The file to template in the date for
+#######################################
+replace_date_placeholders_in_file() {
+	local file="${1}"
+	local current_date
+	current_date="$(date +"%d\/%m\/%Y")"
+	sed -ri "s/(<dstamp>|<date>)/$current_date/g" "$file"
+
+}
+
+#######################################
+# Replace all instances of <mname> or <muname> with a municipality name in place
+# for the given file
+# Arguments:
+#   file: The file to template in the municipality name for
+#   municipality_name: The municipality name to use, or the default if not
+#   provided
+#######################################
+replace_municipality_name_placeholders_in_file() {
+	local file="${1}"
+	local municipality_name="${2:-City of Brook Haven, Connecticut}"
+	sed -ri "s/(<mname>|<muname>)/$municipality_name/g" "$file"
+}
+
+#######################################
+# Redact the given file with the included sed script in place for the given file
+# Arguments:
+#   file: The file to redact
+#######################################
+redact_file() {
+	local file="${1}"
+	sed -ri -f "${SCRIPT_DIR}/assign2.sed" "$file"
+}
+
+#######################################
+# Check that the given file can be used within the script. For example, check
+# that the current script/user has read & write permissions for the given file.
+# Arguments:
+# 	file: The file to check
+#######################################
+check_file() {
+	local file="${1}"
+	if ! [[ -r "$file" ]]; then
+		err "Unable to read '${file}', the current user lacks read permissions or the file does not exist!"
+		return 1
+	fi
+
+	if ! [[ -w "$file" ]]; then
+		err "Unable to modify '${file}', the current user lacks write permissions!"
+		return 1
+	fi
+}
+
+#######################################
+# Check all given files and return a single error code if any given check fails.
+# This is done so all errors for the given files are output to the user prior to
+# exiting.
+# Arguments:
+# 	files: an array of files to loop through and validate
+#######################################
+validate_files() {
+	local ret_code=0
+	local files=("${@}")
+	for file in "${files[@]}"; do
+		if ! check_file "$file"; then
+			ret_code=1
+		fi
+	done
+	return "$ret_code"
+}
+
+main() {
+	local files=("${@}")
+	if (("${#files[@]}" == 0)); then
+		usage
+		die "No arguments provided!"
+	fi
+
+	validate_files "${files[@]}" || die "File checks failed, refusing to run script!"
+
+	for file in "${files[@]}"; do
+		redact_file "$file"
+		replace_date_placeholders_in_file "$file"
+		replace_municipality_name_placeholders_in_file "$file"
+	done
+}
+
+main "${@}"

Summer-2024/CS-3424/Assignments/Assignment-2/src/assign2.sed

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+# Redact Driver's License numbers
+s/[a-zA-Z]{2}\s?DL [0-9]{6,8}/DL <redacted>/g
+
+# Redact Credit Card Numbers
+## Visa Cards
+s/4[0-9]{3}-?[0-9]{4}-?[0-9]{4}-?([0-9]{4})/VISA-\1/g
+## Master Cards
+s/5[0-9]{3}-?[0-9]{4}-?[0-9]{4}-?([0-9]{4})/MC-\1/g
+## Discover Cards
+s/6[0-9]{3}-?[0-9]{4}-?[0-9]{4}-?([0-9]{4})/DISC-\1/g
+## Amex Cards (Important that it comes last because it collides inside larger card lengths)
+s/3[47][0-9]{2}-?[0-9]{6}-?[0-9]([0-9]{4})/AMEX-\1/g
+
+# Redact license plates
+s/TX\s?[[:alnum:]]{3}-?([[:digit:]]{4}|[[:alnum:]]{3})/TX <redacted>/g