Validators

Django Menu Generator uses validators to allow the displaying of menu items.

A validator is a function that receives the request as arg and returns a boolean indicating if the check has passed

for Django Menu Generator the validators must always be a list containing at least one callable or python path to a callable. If there is more than one validator, all of them will be evaluated using the AND connector.

Built-in validators

Django Menu Generator has the following built-in validators:

• is_superuser:

  A validator to check if the authenticated user is a superuser

  Usage:

  "validators": ['menu_generator.validators.is_superuser']
  

• is_staff:

  A validator to check if the authenticated user is member of the staff

  Usage:

  "validators": ['menu_generator.validators.is_staff']
  

• is_authenticated:

  A validator to check if user is authenticated

  Usage:

  "validators": ['menu_generator.validators.is_authenticated']
  

• is_anonymous:

  A validator to check if the user is not authenticated

  Usage:

  "validators": ['menu_generator.validators.is_anonymous']
  

• user_has_permission:

  A validator to check if the user has the given permission

  Usage:

  "validators": [
      ('menu_generator.validators.user_has_permission', 'app_label.permission_codename')
  ]
  

• More than one validator:

  You can pass more than one validator to evaluate using the AND connector

  "validators": [
      'menu_generator.validators.is_staff',
      ('menu_generator.validators.user_has_permission', 'some_app.some_permission')
      ...
  ]
  

Custom validators

You can build your own validators and use them with Django Menu Generator

Let’s build a validator that checks if the user have more than one pet (dummy example) assuming the user has a many to many relation called pets

Assuming we build the function inside your_project/app1 on a menu_validators.py we have:

# Remember you always must to past the request as first parameter
def has_more_than_one_pet(request):

    return request.user.pets.count() > 0

So we can use it as a validator

"validators": ['your_project.app1.menu_validators.has_more_than_one_pet']

Now let’s build a validator that checks if the user’s pet belongs to a specific type to illustrate the validators with parameters.

Assuming we build the function inside the same path and the user have a foreign key called pet

def has_a_pet_of_type(request, type):

    return request.user.pet.type == type

So we use the validator like this:

"validators": [
    ('your_project.app1.menu_validators.has_a_pet_of_type', 'DOG')
]

As you can see, we use tuples to pass parameters to the validators, where the first position is the validator and the rest are the function parameters