Custom TastyPie resource that returns the correct HTTP status code when

api.py

from tastypie import http
from tastypie.exceptions import ImmediateHttpResponse
from tastypie.resources import ModelResource

class CustomModelResource(ModelResource):
	def obj_get(self, request=None, **kwargs):
		try:
			return super(CustomModelResource, self).obj_get(request=request, **kwargs)
		except ObjectDoesNotExist:
			# only branch if kwargs were supplied, which indicates filtering
			# should be applied. If there's no search parameters (not even a pk),
			# then testing for existence is pointless and can cause incorrect
			# returning of http.HttpUnauthorized() (sometimes this method is
			# called on a related resource without any kwargs).
			if kwargs:
				exists = self.get_object_list(request).filter(**kwargs).exists()
				# If the object exists but this particular user doesn't have access,
				# then we should let users know they're unauthorized instead of 
				# saying the object doesn't exist. Also, if TastyPie thinks the
				# object doesn't exist, sometimes it'll try to recreate it (such
				# as during a PUT request), resulting in a DB integrity error
				# from trying to insert an existing primary key, and this snippet
				# prevents that.
				if exists:
					raise ImmediateHttpResponse(response=http.HttpUnauthorized())
			raise