Usually users' profiles are stored in single model. When there are multiple user types, separation is made by some field like user_type.
Situation is a little more complicated when different data is needed for each user type.
Of course it's better when all users have same type and are granted different permissions. But since we got task to have separate user types - we'll have to solve it.
Simple solution
The most obvious solution is to make base profile with type identifier, which will pull needed model instance:
request.user.get_profile().get_final_profile()But I don't really like this solution. Firstly, get_final_profile method is basically a big switch-case. Secondly - we must not forget to call extra method.
I wanted to simply write request.user.profile ans get needed profile instance. This is possible by combining two known tricks - Upcast and AutoOneToOneField.
Upcast
Allows to get sublass instance from base class instance.
AutoOneToOneField
Allows creating related objects on request. This field is not needed per se, only idea. Taking AutoOneToOneField as a base, it's easy to create a new one that calls upcast when related objects is requested.
Solution
class UpCastModel(models.Model):
"""
Base class for models that are ment to be inherited.
Introduces upcast method that returns child instance.
"""
final_type = models.ForeignKey(ContentType, editable=False)
def save(self, args, **kwargs):
if not self.pk:
self.final_type = ContentType.objects.get_for_model(type(self))
super(UpCastModel, self).save(args, **kwargs)
def upcast(self):
if not hasattr(self, '_upcast'):
if self.final_type.model_class == self.class:
self._upcast = self
else:
self._upcast = self.final_type.get_object_for_this_type(id=self.pk)
return self._upcast
class Meta:
abstract = True
class UpCastSingleRelatedObjectDescriptor(SingleRelatedObjectDescriptor):
def get(self, instance, instance_type=None):
parent = super(
UpCastSingleRelatedObjectDescriptor, self
).get(instance, instance_type)
return parent.upcast()
class UpCastOneToOneField(models.OneToOneField):
"""
UpCastOneToOneField gets child of related object.
"""
def contribute_to_related_class(self, cls, related):
setattr(
cls, related.get_accessor_name(),
UpCastSingleRelatedObjectDescriptor(related)
)
Now profile looks like this:
class BaseProfile(UpcastModel):
user = UpCastOneToOneField(User)
class BoyProfile(BaseProfile):
pass
class GirlProfile(CitizenProfile):
passIn order to get users, profile, we just need to write requst.user.profile.
Subscribe for the news and updates
This article explores Figma’s Dev Mode, a tool that streamlines design-to-code translation by enabling precise inspection, automated code generation, and seamless integration with design systems.
Tired of boring programming courses where you're forced to read thick textbooks and write code that's never used? Need a platform that makes learning fun and exciting? Then you're in the right place!
In our article, you will find the best JavaScript framework comparison so that you know for sure how to choose the right one for your project.
We have reviewed the top web frameworks for server and client-side development and compared their pros and cons. Find out which one can be a great fit for your next project.
There was a task to submit form with ajax, with server side validation of course. Obvious solution is to do validation and return json with erros. I didn't like idea of writing separate view for validation and then inserting errors in form html on client side. Especially since I already had a generic template for django form with errors display. In this article I'll describe how I solved the task.
In UNIX way, each view should solve single task. This is good idea, but sometimes we need to mix logic of different views on same page. Filter, sort, paginate, or, for example, add comment on product page. In this article I'll show how we can mix such multiple views.