Question

我有一个Django应用程序，其视图接受要上载的文件。使用Django REST框架我将APIView子类化并实现post（）方法，如下所示：

class FileUpload(APIView):
    permission_classes = (IsAuthenticated,)

    def post(self, request, *args, **kwargs):
        try:
            image = request.FILES['image']
            # Image processing here.
            return Response(status=status.HTTP_201_CREATED)
        except KeyError:
            return Response(status=status.HTTP_400_BAD_REQUEST, data={'detail' : 'Expected image.'})

现在我正在尝试编写几个单元测试，以确保需要进行身份验证，并且实际处理了上载的文件。

class TestFileUpload(APITestCase):
    def test_that_authentication_is_required(self):
        self.assertEqual(self.client.post('my_url').status_code, status.HTTP_401_UNAUTHORIZED)

    def test_file_is_accepted(self):
        self.client.force_authenticate(self.user)
        image = Image.new('RGB', (100, 100))
        tmp_file = tempfile.NamedTemporaryFile(suffix='.jpg')
        image.save(tmp_file)
        with open(tmp_file.name, 'rb') as data:
            response = self.client.post('my_url', {'image': data}, format='multipart')
            self.assertEqual(status.HTTP_201_CREATED, response.status_code)

但是当REST框架尝试对请求进行编码时，这会失败

Traceback (most recent call last):
  File "/home/vagrant/.virtualenvs/myapp/lib/python3.3/site-packages/django/utils/encoding.py", line 104, in force_text
    s = six.text_type(s, encoding, errors)
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xff in position 118: invalid start byte

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/vagrant/webapp/myproject/myapp/tests.py", line 31, in test_that_jpeg_image_is_accepted
    response = self.client.post('my_url', { 'image': data}, format='multipart')
  File "/home/vagrant/.virtualenvs/myapp/lib/python3.3/site-    packages/rest_framework/test.py", line 76, in post
    return self.generic('POST', path, data, content_type, **extra)
  File "/home/vagrant/.virtualenvs/myapp/lib/python3.3/site-packages/rest_framework/compat.py", line 470, in generic
    data = force_bytes_or_smart_bytes(data, settings.DEFAULT_CHARSET)
  File "/home/vagrant/.virtualenvs/myapp/lib/python3.3/site-packages/django/utils/encoding.py", line 73, in smart_text
    return force_text(s, encoding, strings_only, errors)
  File "/home/vagrant/.virtualenvs/myapp/lib/python3.3/site-packages/django/utils/encoding.py", line 116, in force_text
    raise DjangoUnicodeDecodeError(s, *e.args)
django.utils.encoding.DjangoUnicodeDecodeError: 'utf-8' codec can't decode byte 0xff in position 118: invalid start byte. You passed in b'--BoUnDaRyStRiNg\r\nContent-Disposition: form-data; name="image"; filename="tmpyz2wac.jpg"\r\nContent-Type: image/jpeg\r\n\r\n\xff\xd8\xff[binary data omitted]' (<class 'bytes'>)

如何让测试客户端发送数据而不尝试将其解码为UTF-8？

Answer 1

在测试文件上传时，您应该将流对象传递给请求，而不是数据。

@arocks

的评论指出了这一点

传递{'image'：file}而不是

但这并没有完全解释为什么需要它（也与问题不符）。对于这个具体问题，你应该做

class TestFileUpload(APITestCase):

    def test_file_is_accepted(self):
        self.client.force_authenticate(self.user)

        image = Image.new('RGB', (100, 100))

        tmp_file = tempfile.NamedTemporaryFile(suffix='.jpg')
        image.save(tmp_file)

        response = self.client.post('my_url', {'image': tmp_file}, format='multipart')

       self.assertEqual(status.HTTP_201_CREATED, response.status_code)

这将匹配标准的Django请求，其中文件作为流对象传入，Django REST Framework处理它。当您传入文件数据时，Django和Django REST Framework将其解释为字符串，这会导致问题，因为它期待流。

对于那些来这里寻找另一个常见错误的人，为什么文件上传不起作用，但正常的表单数据会：确保在创建请求时设置format="multipart" 。< / p>

这也提出了类似的问题，@RobinElvin在评论中指出了

这是因为我缺少format ='multipart'

Answer 2

Python 3用户：确保open中的文件mode='rb'（读取，二进制）。否则，当Django在文件上调用read时，utf-8编解码器将立即开始阻塞。该文件应解码为二进制而不是utf-8，ascii或任何其他编码。

# This won't work in Python 3
with open(tmp_file.name) as fp:
        response = self.client.post('my_url', 
                                   {'image': fp}, 
                                   format='multipart')

# Set the mode to binary and read so it can be decoded as binary
with open(tmp_file.name, 'rb') as fp:
        response = self.client.post('my_url', 
                                   {'image': fp}, 
                                   format='multipart')

Answer 3

对于Windows中的用户，答案有点不同。我必须做以下事情：

resp = None
with tempfile.NamedTemporaryFile(suffix='.jpg', delete=False) as tmp_file:
    image = Image.new('RGB', (100, 100), "#ddd")
    image.save(tmp_file, format="JPEG")
    tmp_file.close()

# create status update
with open(tmp_file.name, 'rb') as photo:
    resp = self.client.post('/api/articles/', {'title': 'title',
                                               'content': 'content',
                                               'photo': photo,
                                               }, format='multipart')
os.remove(tmp_file.name)

正如此答案（https://stackoverflow.com/a/23212515/72350）中所指出的那样，该文件在Windows中关闭后无法使用。在Linux下，@ Meistro的答案应该有效。

Answer 4

如果你想使用PATCH方法，理解如何做到这一点并不是那么简单，但我在this question中找到了解决方案。

from django.test.client import BOUNDARY, MULTIPART_CONTENT, encode_multipart

with open(tmp_file.name, 'rb') as fp:
    response = self.client.patch(
        'my_url', 
        encode_multipart(BOUNDARY, {'image': fp}), 
        content_type=MULTIPART_CONTENT
    )

Answer 5

您可以使用内置的Django SimpleUploadedFile：

from django.core.files.uploadedfile import SimpleUploadedFile

class TestFileUpload(APITestCase):
...

    def test_file_is_accepted(self):
        ...

       tmp_file = SimpleUploadedFile(
                      "file.jpg", "file_content", content_type="image/jpg")

       response = self.client.post(
                      'my_url', {'image': tmp_file}, format='multipart')
       self.assertEqual(response.status_code, status.HTTP_201_CREATED)

如何使用django-rest-framework的测试客户端测试二进制文件上传？

5 个答案: