python - Django Serializer Save models with foreign key relationships -

i trying save model object has foreign key referencing table. trying write serializer same, can't wrap head around how , can't seem find right documentation either. model objects:

class restaurant(models.model):      name = models.charfield(null=false, max_length=255)     min_order = models.charfield(null=false, max_length=255)     # , on  class rmenucategory(models.model):      category_name = models.charfield(null=false, max_length=255)     restaurant = models.foreignkey('restaurant') 

my serializer class rmenucategory model:

class restaurantmenuserializer(serializers.modelserializer):      restaurant = serializers.primarykeyrelatedfield()      class meta:         model = rmenucategory         fields = ('id', 'category_name', 'restaurant') 

making api call json as:

{ "category_name" : "italian", "restaurant_id" : 4} 

this not working when try out following in view:

menu_cat = restaurantmenuserializer(data=data)         if menu_cat.is_valid():             category = menu_cat.save()         else:             exit() 

change restaurant_id restaurant:

{ "category_name" : "italian", "restaurant" : 4}