在将DRF Serializer转换为DRF ModelSerializer后,在进行单元测试时可能会遇到AssertionError错误。这是因为它们在处理空值(null)方面的方式不同。Serializer将空值序列化为null,而ModelSerializer将其视为有效值。因此,对于ModelSerializer,我们需要使用allow_null=True来处理空值。下面是代码示例:
from rest_framework import serializers
class MySerializer(serializers.Serializer):
some_field = serializers.IntegerField()
class MyModelSerializer(serializers.ModelSerializer):
some_field = serializers.IntegerField(allow_null=True)
class Meta:
model = MyModel
fields = '__all__'
在进行单元测试时,我们需要相应地修改测试用例,以处理由空值引起的错误。在Serializer中,我们可以使用assertEqual(None, result.data)来测试结果是否为空。如果我们使用了ModelSerializer,则必须改为使用assertEqual(None, result.data['some_field'])。
代码示例:
from django.test import TestCase
from rest_framework.test import APIClient
from myapp.models import MyModel
from myapp.serializers import MySerializer, MyModelSerializer
class MyTestCase(TestCase):
def setUp(self):
self.client = APIClient()
self.test_data = {'some_field': None}
self.test_model = MyModel.objects.create(some_field=None)
def test_serializer(self):
serializer = MySerializer(data=self.test_data)
self.assertTrue(serializer.is_valid())
result = serializer.save()
self.assertEqual(None, result.some_field)
def test_model_serializer(self):
serializer = MyModelSerializer(data=self.test_data)
self.assertTrue(serializer.is_valid())
result = serializer.save()
self.assertEqual(None, result.some_field)
def test_get(self):
response = self.client.get('/my/model/{}/'.format(self.test_model.pk))
self.assertEqual(response.status_code, 200)
self.assertEqual(None, response.data['some_field'])
注意,我们需要在Serializer和ModelSerializer两个测试用例中都包含一个测试。在这些测试中,通过使用allow_null=True来处理空值,以保证单元测试的正确性。