wrap-multipart-params creates an empty file when an empty file input is submitted about ring HOT 4 CLOSED

Is there a way of reliably determining, for all browsers, whether the file has been omitted from the input, or whether a zero-byte file has been submitted?

from ring.

Hadn't thought about that, but it looks like that can be determined from the filename:

-----------------------------264040574727381079401146929549
Content-Disposition: form-data; name="image"; filename="zerobytes.png"
Content-Type: image/png


-----------------------------264040574727381079401146929549

VS

-----------------------------6155252271109589944108876070
Content-Disposition: form-data; name="image"; filename=""
Content-Type: application/octet-stream


-----------------------------6155252271109589944108876070

This behaviour is the same for Firefox, Chrome and Safari.

But going into the nitty grittys, I can't find a canonical reference for how you can determine this.
RFC2388 seems to say the filename is optional.

So I'd suggest to only nil it when the filename is empty?

from ring.

I suspect there isn't a foolproof way of determining this, so I think the current behavior of Ring will have to remain. However, what you could do is to make some additional middleware in your project to update zero-byte files to nil responses.

from ring.

ok thats fair! just wasted an hour on this, so thought i would ask about it to save someone else the time. But you're likely right in that it cant be 100% accurately determined.

Thanks for the quick reply!

from ring.