general-scripts-and-system-ssssssetup/References/Quick-and-Dirty-Methods-Bash.md

Quick and Dirty Methods (Bash)

colors

# Define color variables
PINK='\e[35m'
BRIGHT_PINK='\e[95m'
RED='\033[0;31m'
YELLOW='\033[1;33m'
GREEN='\033[0;32m'
RESET='\033[0m' # No Color (RESET)
# usage echo -e "$PINKpinktext here$RESET"

standard peak safety with error handling for shell scripts shell script header to exit on error, failed piping, or unset variable while allowing err trap and custom trapping for error

#!/bin/bash
# set safety optinonz
set -o errexit # fail on error
set -o errtrace # run trace on error
set -o pipefail # fail on pipe fail
set -o nounset # fail on unset var

# save here to use in error_handle function
num_of_args="$#"
all_args="$@"

# Define the cleanup function
error_handle() {
    # CRITICAL: Capture the exit status code before ANY other command runs
    local exit_code=$?
    local script_path="$(realpath $0)"
    local hr='===================================================='
    echo
    echo $hr
    echo -e "🚨 \033[0;31m FATAL ERROR DETECTED \033[0m"
    echo $hr
    echo "-> Script            : $0"
    echo "-> Num Script Args   : $num_of_args"
    echo "-> Script Args       : $all_args"
    echo "-> Shell             : $SHELL"
    echo "-> Script Path       : $script_path"
    echo "-> Script (full)     : $SHELL $script_path $all_args"
    echo "-> User              : $USER"
    echo "-> Working Directory : $PWD"
    echo "-> Failed Command    : $BASH_COMMAND"
    echo "-> Line Number       : $LINENO"
    echo "-> Exit Status       : $exit_code"
    echo "-> Seconds Elapsed   : $SECONDS"
    echo "-> Date Failed       : $(date)"
    # Generate a professional, clean stack traceback
    echo "-> Stack Trace"
    printf "\t" # to intent da stack trace
    local frame=0
        # Loop backwards through the function execution stack array
    while caller $frame; do
        printf "\t" # to indenet da stack trace
        frame=$((frame + 1))
    done

    # closing niceties
    echo
    echo $hr
    echo

    # exit with last failcode
    exit "$exit_code"
}

trap error_handle ERR

show every set variale and its value (one liner)

for v in $(compgen -v); do echo "$v:$$v"; done

run command and display error or success

<command>; ret=$? && if [ $ret -ne 0 ]; then echo -e "\n\033[0;31mERRROR! Code: $ret\033[0m"; else echo -e "\033[0;32mOK!\033[0m"; fi

Function to Display succ/err based on error code

checkcode () {
    if [ -z "$1" ]; then
        echo -e "\n\e[31mERROR!\033[0m chkcode missing return code paramater\n"
        exit 1
    else
        retcode=$1
    fi

    if [ $retcode -ne 0 ]; then
        echo -e "\t\e[31mERROR!\033[0m Response Code: $retcode"
    else
        echo -e "\t\e[1;32mOK!\e[0m"
    fi
}

Test a list of commands if they are present

cmds_to_check=(sha256sum sha1sum md5sum openssl scrypt)
for cmd in ${cmds_to_check[@]}; do
    if command -v $cmd &>/dev/null; then
        # echo -e "\033[0;32mOK!\033[0m $cmd is present"
        continue
    else
        echo -e "\n\n\033[0;31mERROR!\033[0m $cmd not found! please intall! Exiting!\n\n" >&2
        exit 1
    fi
done
echo -e "\033[0;32mOK!\033[0m All Needed Commands Available!"