user-mgmt/management/user-mgmt.sh

#!/bin/bash
# User Management Script, powered by an SQL database
# (c) Sangelo | Read Licenses for more info: https://gitpot.dev/sangelo/user-mgmt

# Variables
E_BADARGS=65
MYSQL=`which mysql`
MYSQL_USER="root"
USAGE="
$0 -- user management script
Usage:
    init
    add     {username} {name} {description}
    delete  {username}
    list
"

# Check for correct number of arguments and action
if [ $# -lt 1 ]
then
  echo "$USAGE"
  exit $E_BADARGS
fi

# Switch between different actions
case "$1" in
  "init")
    Q1="CREATE SCHEMA if not exists usermgmt; use usermgmt; CREATE TABLE if not exists users (username varchar(255), name varchar(255), description varchar(255));"
    SQL="${Q1}"
    ;;
  "add")
    if [ $# -ne 4 ]
    then
      echo "Error: Invalid action."
      echo "$USAGE"
      exit $E_BADARGS
    fi
    Q1="INSERT INTO usermgmt.users (username, name, description) VALUES ('$2', '$3', '$4');"
    SQL="${Q1}"
    ;;
  "delete")
    if [ $# -ne 2 ]
    then
      echo "Error: Invalid action."
      echo "$USAGE"
      exit $E_BADARGS
    fi
    Q1="DELETE FROM usermgmt.users WHERE username = '$2';"
    SQL="${Q1}"
    ;;
  "list")
    if [ $# -ne 1 ]
    then
      echo "Error: Invalid action."
      echo "$USAGE"
      exit $E_BADARGS
    fi
    Q1="SELECT username, name, description FROM usermgmt.users;"
    SQL="${Q1}"
    ;;
  *)
    echo "Error: Invalid action. Please use a valid argument."
    echo "$USAGE"
    exit $E_BADARGS
    ;;
esac

$MYSQL -u "$MYSQL_USER" -p -e "$SQL"