Saving StringIO using custom storage class may result in empty content written to file

[Maxim Novikov]

​https://github.com/django/django/blob/master/django/core/files/storage.py#L50

class Storage(object):

    def save(self, name, content, max_length=None):
        ...
        if not hasattr(content, 'chunks'):
            content = File(content)

For example if custom storage uses requests with post query and we are saving StringIO object.

from StringIO import StringIO

from django.core.files.storage import Storage
import requests

class CustomStorage(Storage):
    def _save(self, name, content, max_length=None):
          requests.post('http://testhost.org/upload', data=content)
custom_storage = CustomStorage()
custom_storage.save('new_name', StringIO('content'))

But it will result in empty upload as bool(content) is False.
Possibly better to pass a name to File object. To ensure bool(content) is True

    if not hasattr(content, 'chunks'):
        content = File(content, name=name)

[Tim Graham]

It's not clear to me how to reproduce the issue. In particular I'm not sure what the store method refers to (I don't see anything in Django itself with that name). Please try to include more details such as a test for Django's test suite (ideally) or a sample project.

[Tim Graham]

Thanks for updating the description. It's still not entirely clear to me where the problem lies or how the proposed change will fix it. Any chance you could offer a tested patch? Otherwise, I'm not too sure how to proceed here.

[Maxim Novikov]

Patch ​https://github.com/django/django/pull/6448

[Tim Graham]

It's a bit odd to me that bool(file) is based on the file's name, but in light of that, I guess this makes sense.

[Tim Graham <timograham@…>]

In 4d1c229e:

Fixed #26495 -- Added name arg to Storage.save()'s File wrapping.