Browsable API shows error message on successful image upload.

[LilyFoote]

The code I used to test this can be found at image-upload-test.

[tomchristie]

This is most likely to be a PIL/codec issue? (Eg we've had problems with sorl-thumbnail when users upload certain images with thumbnailing those images, but the problem has never been to do with sorl-thumbnail itself, just with the codecs that happened to be installed on the system not supporting the uploaded image)

Marked as easy pickings, as it's not too much work to figure out if we can mark this ticket as resolved. Set up a model with an image field, and create a basic view for editing it. Can you upload any images or not. If so then I believe we can close this issue. If not then this needs more attention.

[LilyFoote]

Just to clarify: The image upload itself succeeds. The problem is the incorrectly displayed error message.

[tomchristie]

Ah gotcha. Occurring for all cases, or just some images?

[LilyFoote]

It occurs for all the jpg and png images I've tested with.

[kevin-brown]

This sounds like an issue with the Django form and how the data is populated, not with the core of DRF.

[koepked]

I have this too and did some poking around. I don't think it's in Django form, I think it's in rest_framework.fields.ImageField.from_native():

try:
            # load() could spot a truncated JPEG, but it loads the entire
            # image in memory, which is a DoS vector. See #3848 and #18520.
            # verify() must be called immediately after the constructor.
            Image.open(file).verify()
        except ImportError:
            # Under PyPy, it is possible to import PIL. However, the underlying
            # _imaging C module isn't available, so an ImportError will be
            # raised. Catch and re-raise.
            raise
        except Exception:  # Python Imaging Library doesn't recognize it as an image
            print 'Here it is...'
            raise ValidationError(self.error_messages['invalid_image'])

If I upload the photo using django-admin instead, the form validates fine. I don't know if it matters or not, but from_native() gets called twice on upload and the exception occurs on the 2nd.

[kevin-brown]

The serializer is used to generate the Django form automatically. During the process I believe from_native is called, which would explain the errors that occur in one place and not the other.

[koepked]

On the second call, file in Image.open(file).verify() appears to be empty.

[tomchristie]

Should be resolved as part of 3.0

[carltongibson]

Can we close this? #1681 — which addresses this was confirmed as fixed in 3.0.