def test_invalid_field_by_order(self):
        ItemFactory.create_batch(4)
        ItemFactory.create(title='title_0')

        got = self.client.get('/posts', {'order': 'invalid_field'})

        self.assertListEqual([item['title'] for item in got.data],
                             [i.title for i in Item.objects.order_by('id')])
    def test_response(self):
        item = ItemFactory.create()

        got = self.client.get('/posts')

        data = got.data[0]

        self.assertEqual(data['id'], item.id)
        self.assertEqual(data['title'], item.title)
        self.assertEqual(data['url'], item.url)
        self.assertEqual(data['created'],
                         item.created.strftime('%Y-%m-%dT%H:%M:%S.%f'))