how to unit test file upload in django

Question

In my django app, I have a view which accomplishes file upload.The core snippet is like this

...
if  (request.method == 'POST'):
    if request.FILES.has_key('file'):
        file = request.FILES['file']
        with open(settings.destfolder+'/%s' % file.name, 'wb+') as dest:
            for chunk in file.chunks():
                dest.write(chunk)

I would like to unit test the view.I am planning to test the happy path as well as the fail path..ie,the case where the request.FILES has no key 'file' , case where request.FILES['file'] has None..

How do I set up the post data for the happy path?Can somebody tell me?

Answer 1

I used to do the same with open('some_file.txt') as fp: but then I needed images, videos and other real files in the repo and also I was testing a part of a Django core component that is well tested, so currently this is what I have been doing:

from django.core.files.uploadedfile import SimpleUploadedFile

def test_upload_video(self):
    video = SimpleUploadedFile("file.mp4", "file_content", content_type="video/mp4")
    self.client.post(reverse('app:some_view'), {'video': video})
    # some important assertions ...

In Python 3.5+ you need to use bytes object instead of str. Change "file_content" to b"file_content"

It's been working fine, SimpleUploadedFile creates an InMemoryFile that behaves like a regular upload and you can pick the name, content and content type.