Question

I have 2 functions from separate scripts that communicate. What should happen is, if a value exists, a variable should be set to %username%; if the value doesn’t exist it should be set to “None”. If the variable is set to none, the function should continue and create a new account. If the variable is set to a username, the function should continue. So, why am I getting inconsistent, erratic results?

Functions as follow, they won’t run as they call other functions that aren’t included:

def database_get_user_details(user_database, username, detail):
    value = "None"
    rows = ((users_db_curs.execute("SELECT * FROM '" + user_database + "' WHERE username='" + username + "'"))).fetchall()
    for row in rows:
        if rows:
            if detail   == ("userID")     : value = str(row[1])
            elif detail == ("username")   : value = str(row[2])
            elif detail == ("password")   : value = str(row[3])
            elif detail == ("creator_exp"): value = str(row[4])
            else                          : value = "None"
        else:
            value = "None"
    return value

def game_register(username_table_name):
    while True:
        while True:
            user_ID = raw_input("E-mail address: ")
            if user_ID != "":
                break
        while True:
            username = raw_input("Username      : ")
            if username != "":
                break
        while True:
            password = raw_input("Password      : ")
            if password != "":
                password = password.encode("hex")
                break
        usr = database_get_user_details(username_table_name, username, "username")
        print usr
        if (usr != "None") or (usr != None):
            print usr
            print "Username already taken!"
            pause()
        else:
            database_create_user(username_table_name, user_ID, username, password, "250")
            print "Successfully created %s with password: %s" %(username, password.decode("hex"))
            pause()
            break

Please note, I have not included the actual password encryption algorithm for security – I have just set it to encode to hex in this example.

Edit: Forgot to explain

It is almost as though I am calling random.choice(), I can’t find any consistency relating to whether or not the function creates a new user, or tells me that username has already been used.

Answer 1

Your code for existing users will always trigger because at least one of the inequalities will be true.

if (usr != "None") or (usr != None):
        print usr
        print "Username already taken!"
        pause()

The condition should be

if (usr != "None") and (usr != None):