What methods are used to verify user rights in the system?

User rights verification in the system can be carried out in several ways:

1. Authentication and Authorization:

   • Authentication is confirming the user's identity (login, password, tokens).
   • Authorization checks whether the user has rights to perform an action or access a resource.

2. Role-Based Access Control (RBAC):

   • Users are assigned roles (admin, user, guest).
   • Each role has a set of permissions.

3. Discretionary Access Control (DAC):

   • The resource owner determines who can perform what actions.

4. Mandatory Access Control (MAC):

   • The system itself determines access rights based on security policies.

5. Code-level rights checking:

   • Using decorators or middleware to check permissions before executing a function.

Example of rights checking in Python using a decorator:

def requires_admin(func):
    def wrapper(user, *args, **kwargs):
        if not user.is_admin:
            raise PermissionError("Access denied")
        return func(user, *args, **kwargs)
    return wrapper

@requires_admin
def delete_user(user, user_id):
    print(f"User {user_id} has been deleted")

class User:
    def __init__(self, is_admin):
        self.is_admin = is_admin

admin = User(is_admin=True)
user = User(is_admin=False)

delete_user(admin, 123)  # Works
# delete_user(user, 123)  # Will raise PermissionError

Thus, rights verification is a comprehensive measure that includes user identification and permission checks for specific actions.