Create a new Debian based non-root user with specified group

spawn_user.sh

#!/bin/bash

#####################################
# File: spawn_user.sh
# Description: Create a new Debian based non-root user with specified group
# Created: Thursday, 2nd June 2021 
# Author: Anjum Rashid 
# -----
# Last Modified: Tuesday, Thursday, 3rd June 2021
# -----
#####################################

# make sure to run script as root or sudoer (sudo ./spawn_user.sh)

function collectUserInfo() {

	echo "Enter new username:"
	read username

	checkExistingUser
	
	echo "Enter new password:"
	read password

	echo "Enter groupname (existing) to assign:"
	read group

	checkExistingGroup
}

function checkExistingUser(){

	# check if 'id' finds a user or not
	# 'id -u username' displays the uid only. '$?' contains the return status (0 or 1) 	
	status_code=$(id -u "$username" &>/dev/null; echo $?)

	if [[ $status_code -eq 1 ]] ; then  
    	  echo 'Cool choice!'
	else
    	  echo 'User already exists. Try again with a different username'
	  exit $status_code  
	fi

}

function checkExistingGroup(){

	# 'grep group /etc/group' displays matching group info 	
	status_code_grp=$(grep -q $group /etc/group; echo $?)
		
	if [[ $status_code_grp -eq 1 ]] ; then  
    	  echo "Group "$group" does not exist. Try again with an existing group"
	  exit $status_code_grp  
	else
    	  echo ""$group" group selected for assignment."
	fi
}

function setupNewUser() {
	
	echo -e "\n################## STATUS LOG ##################\n"

	# add new user, set group, create new home directory 
	useradd -G $group -m $username			 

	echo "new user $username created and user group $group assigned!" 

	# update new user password by piping from STDIN
	echo ""$username":"$password"" | chpasswd			

	echo "user password for $username is set!"

	# change the default user shell to bash 
	chsh -s /bin/bash $username		

	echo "user $username shell updated to bash!"		
}


function verifyUser() {
	echo -e "\n################## NEW ENTRIES ##################\n"
	
	echo -e "User entry (etc/passwd):\n\n\t$(grep "$username" /etc/passwd)\n" 	
	echo -e "Password entry (etc/shadow):\n\n\t$(grep "$username" /etc/shadow)\n"	 
	echo -e "Group entry (etc/group):\n\n\t$(grep "$group" /etc/group)\n"
}

collectUserInfo
setupNewUser
verifyUser