Reference data everybody reads

A list of branches, the kinds of loan: everybody signed in reads them, to choose one, and few change them. Gating the reads protects nothing and makes every form refuse a choice.

The rows

from clearance.querysets import SignedInReadQuerySet


class Branch(models.Model):
    name = models.CharField(max_length=80)

    objects = SignedInReadQuerySet.as_manager()

Every row, for anybody signed in, whatever they hold - so a serializer's or a form's field choosing a branch offers every branch. Somebody signed out, or switched off, reaches none.

The writes

Who may change a branch is still a permission: change_branch, given like any other. For an API that lists branches to anybody signed in, give the model a policy that reads the same way:

from clearance.policies import SignedInReadPolicy
from clearance.registry import registry


class BranchPolicy(SignedInReadPolicy):
    model = Branch


registry.register(BranchPolicy)

Reading is open to anybody signed in; creating, editing and deleting ask the permissions.