function-decorator , which is checking an access according to USERNAME

[Liki]

Hallo,

I'm asking for help for followed task:

"""
Realize a function-decorator , which is checking an access according to USERNAME
All USERNAMEs are saved as global in the List USERS
If User is agree for authorisation - he should input his username (saved as global)
Funktion should use two decorators: one for checking of authorisation, second - for check of access
"""

Why is error outputed?:

USERS = ['admin', 'guest', 'director', 'root', 'superstar']

yesno = input(""" Input Y if you want to authorisate yourself or input N if you want to work as an anonyme User """)

auth = yesno == "Y"

if auth:
    username = input("Input your username:")



def is_auth(func):
    def wrapper():
        if auth:
            print("User is authorised")
            func()
        else:
            print("User is not authorised. Function will not performed")
    return wrapper




@is_auth
@has_access
def from_db():
    print("some data from database")

from_db()


###:

def has_access(func):
    def wrapper():
        if username in USERS:
            print("Authorised as", username)
            func()
        else:
            print("Access for user", username, "is not allowed")
    return wrapper

I would like to ask for helping to correct the code

[DPaul]

Without checking the results, you call def has_access(func)
before you have defined it.
P.

[deanhystad]

This code belongs inside your is_auth() decorator

yesno = input(""" Input Y if you want to authorisate yourself or input N if you want to work as an anonyme User """)
 
auth = yesno == "Y"
 
if auth:
    username = input("Input your username:")

This code should be checking if the entered username is in the list of authorized users.

def is_auth(func):
    def wrapper():
        if auth:
            print("User is authorised")
            func()
        else:
            print("User is not authorised. Function will not performed")
    return wrapper

[Liki]

Without checking the results, you call def has_access(func)
before you have defined it.
P.

Thank you.

the error

 Input Y if you want to authorisate yourself or input N if you want to work as an anonyme User Y
Input your username:admin
Traceback (most recent call last):
  File "C:/Users/..........py", line 35, in <module>
    @has_access
NameError: name 'has_access' is not defined

I'm trying to check the results:
a)
I inputed "Y" to autorise myself. The code taked it and

b)
goes to futher step: I inputed username from the list "admin"
and the error-message shows on line 35: @has_access


In the following code-variante I'm placing

def has_access(func):

before I calling

@has_access

:

USERS = ['admin', 'guest', 'director', 'root', 'superstar']

yesno = input(""" Input Y if you want to authorisate yourself or iput N if you want to work as an anonyme User """)

auth = yesno == "Y"


def is_auth(func):
    def wrapper():
        if auth:
            print("User is authorised")
            func()
        else:
            print("User is not authorised. Function will not performed")
    return wrapper


if auth:
    username = input("Input your username:")


###:

def has_access(func):
    def wrapper():
        if username in USERS:
            print("Authorised as", username)
            func()
        else:
            print("Access for user", username, "don't allowed")
    return wrapper
    

@is_auth
@has_access
def from_db():
    print("some data from database")

from_db()

Is the code now correct ? The code is performed:

Input Y if you want to authorisate yourself or iput N if you want to work as an anonyme User Y
Input your username:admin
User is authorised
Authorised as admin
some data from database

To unterstand in full... my futher question to

def from_db():
    print("some data from database")

from_db()

what should hier happen? Should this function output an symbolical text as if some data from database was printed after authorisation "Y" and after input of username "admin" from the list?

[deanhystad]

No, this code really needs to be in your is_auth() decorator.

yesno = input(""" Input Y if you want to authorisate yourself or iput N if you want to work as an anonyme User """)
 
auth = yesno == "Y"

if auth:
    username = input("Input your username:")

The only code that should not be in your decorator is this:

USERS = ['admin', 'guest', 'director', 'root', 'superstar']
 
@is_auth
@has_access
def from_db():
    print("some data from database")
 
from_db()

I would drop the prompt asking if the user wants to enter a username. I would write is_auth to ask the user to enter a username. They can give consent by entering a name or decline by not entering a name. The is_auth decorator only calls the wrapped function if a username is entered.

[Liki]

This code belongs inside your is_auth() decorator

yesno = input(""" Input Y if you want to authorisate yourself or input N if you want to work as an anonyme User """)
 
auth = yesno == "Y"
 
if auth:
    username = input("Input your username:")

This code should be checking if the entered username is in the list of authorized users.

def is_auth(func):
    def wrapper():
        if auth:
            print("User is authorised")
            func()
        else:
            print("User is not authorised. Function will not performed")
    return wrapper

Thank you.

this code works correct also if it is outside of is_auth() decorator
Isn't it?:

USERS = ['admin', 'guest', 'director', 'root', 'superstar']

yesno = input(""" Input Y if you want to authorisate yourself or iput N if you want to work as an anonyme User """)

auth = yesno == "Y"



def is_auth(func):
    def wrapper():
        if auth:
            print("User is authorised")
            func()
        else:
            print("User is not authorised. Function will not performed")
    return wrapper




if auth:
    username = input("Input your username:")


###:

def has_access(func):
    def wrapper():
        if username in USERS:
            print("Authorised as", username)
            func()
        else:
            print("Access for user", username, "don't allowed")
    return wrapper
    

@is_auth
@has_access
def from_db():
    print("some data from database")

from_db()

 Input Y if you want to authorisate yourself or iput N if you want to work as an anonyme User Y
Input your username:root
User is authorised
Authorised as root
some data from database

[deanhystad]

No, it does not work correctly. Try this:

@is_auth
@has_access
def from_db():
    print("some data from database")
 
@has_access
def open_forum():
    print("log onto the forum")
 
from_db()
open_forum()

calling from_db() and open_forum() should each ask if you want to enter credentials. Your code works for one test, it needs to work for all tests.