In my Django application there is an endpoint that handles file upload. In the serializer I define the file size validation like below
extra_kwargs = {
"image_file": {
"validators": [
get_file_size_validator(1e8),
],
},
The validator function looks like this
def get_file_size_validator(file_size):
def validator_func(file):
if file_size < file.size:
raise ValidationError(f"Maximum file size is {file_size}")
return validator_func
I would like to write a test where I want to test that user cannot upload large files.
What I have tried so far.
SimpleUploadedFile("foo.pdf", b"aaaaa" * (9**10), content_type="image/jpeg")
InMemoryUploadedFile(BytesIO(b"large_content"), None, "foo.jpg", "image/jpeg", lambda: 1e9, None, None)
mock.patch.object(InMemoryUploadedFile, "size", return_value=1e9):
os.path.getsize
as recommended here https://stackoverflow.com/a/35246275/1847898The first solution gives me MemoryError and for all the others file size is returned as 13 in validator_func
Any ideas how I can achieve this?
You should mock the MemoryFileUploadHandler.file_complete
method instead of SimpleUploadedFile
or InMemoryUploadedFile
.
from unittest.mock import patch
from django.core.files.uploadedfile import InMemoryUploadedFile, SimpleUploadedFile
from rest_framework.test import APITestCase
class TestUploadAPI(APITestCase):
url = "/api/to/the/end-point/"
@patch("django.core.files.uploadhandler.MemoryFileUploadHandler.file_complete")
def test_validate_size(self, mock_file_complete):
file_name = "any-file-name"
file_content_type = "image/png"
max_size = 1e8
mock_file_complete.return_value = InMemoryUploadedFile(
file=b"",
field_name=None,
name=file_name,
content_type=file_content_type,
size=max_size + 1,
charset=None,
)
file = SimpleUploadedFile(
name=file_name,
content=b"",
content_type=file_content_type,
)
response = self.client.post(self.url, {"file": file})
self.assertEqual(response.status_code, 400)
self.assertEqual(
response.json(),
{
"file": ["Maximum file size is 100000000.0"],
},
)
mock_file_complete.assert_called_once()