main.py

from sys import argv
import psycopg2


def get_connection():
    db_connect = psycopg2.connect(
        host="localhost",
        database="postgres",
        user="postgres",
        password="postgres",
    )
    db_connect.set_session(autocommit=True)
    return db_connect


def is_admin(username: str) -> bool:
    conn = get_connection()
    with conn.cursor() as cursor:
        # UNSECURE
        cursor.execute("""SELECT admin FROM users WHERE username = '%s' """ % username)

        # SECURE
        #cursor.execute("""SELECT admin FROM users WHERE username = %(username)s """, {'username': username})

        result = cursor.fetchone()

    if result is None:
        return False

    admin, = result
    return admin


if __name__ == "__main__":
    username = str(argv[1])
    # is_admin("'; update users set admin = 'true' where username = 'mallory'; select true; --")
    print(username + " is an admin: " + str(is_admin(username)))