Django- Get Foreign Key Model

Question

How can I Get A Foreign Key Model Type?

For Example:

class Category(models.Model):
    name = models.CharField(max_length = 100)

class SubCategory(models.Model):
    category = models.ForeignKey(Category)
    title = models.CharField(max_length = 100)

I Want To Get category Model In SubCategory.

How Can I Do It?

Solution 1

Try:

subcategory = SubCategory.objects.get(pk=given_pk)
subcategory.category

EDIT:

subcategory._meta.get_field('category').rel.to

Solution 2

For Django>=2.0

>>> SubCategory._meta.get_field('category').remote_field.model
>>> 'my_app.models.Category'

To get the model name use the __name__ class property.

>>> SubCategory._meta.get_field('category').remote_field.model.__name__ 
>>> 'Category'

Solution 3

ForeignKeys are ReverseSingleRelatedObjectDescriptor objects. So that's what you are really working with. You'll get that if you run type(SubCategory.category). From here you can use two ways to get the actual Class/Model referred to.

SubCategory.category.field.rel.to  # <class 'path.to.Model'>
SubCategory.category.field.rel.to.__name__  # 'Category'

# or these will do the same thing

SubCategory._meta.get_field('category').rel.to
SubCategory._meta.get_field('category').rel.to.__name__

If you don't know the attribute name until run-time, then use getattr(SubCategory, attributeNameVariable) to get your ReverseSingleRelatedObjectDescriptor object for that ForeignKey field.

Solution 4

also for django > = 2.0

>>> SubCategory._meta.get_field('category').related_model
>>> <class 'my_app.models.Category'>
>>> SubCategory._meta.get_field('category').related_model._meta.model_name
>>> 'category'

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Comments

[Tomek Paczkowski]

Oh... Then is very simple: always Category.

[Admin]

Kidding Me? It's A Sample. I Want The To Get The Foreign Key Dynamically!

[Admin]

You Say True. Thank You Very Very Much :-)

[AnonymousUser]

How to do category = Category.objects.get(pk=given_pk) category.subcategory ? I wanna do it this way, but it's not working.