dashboard.snapcraft.io image collision

[Francisco Jimenez Cabrera]

Hi,

Could you investigate an issue with the following image?

https://dashboard.snapcraft.io/site_media/appmedia/2021/08/logo.png

Apparently, it contained a completely different image at some point, we can still see the previous one because Cloudinary:
https://res.cloudinary.com/canonical/image/fetch/f_auto,q_auto,fl_sanitize,w_60,h_60/https://dashboard.snapcraft.io/site_media/appmedia/2021/08/logo.png

How is it possible that someone is reporting their snap to have a completely different image?

I tried to upload images with the same for different snaps but I couldn't reproduce this issue.

For more info please take a look into the issue reported on the snapcraft.io repo:

https://github.com/canonical-web-and-design/snapcraft.io/issues/3622

Thank you!

[Maximiliano Bertacchini (maxiberta)]

I'm unable to reproduce, but I suspect it's a race condition at django's storage layer.

When a file is uploaded, django's storage (django-storage-swift, in our case) takes a filename, checks if it already exists, and if so it appends and underscore and 7 random alphanumeric chars to it [0]. I think it's possible that if two identically named files (e.g. "logo.png") are uploaded at the same time, and if the storage layer (swift) is slow enough, the 2nd one might end up winning and overwriting the first one. The store could proactively "randomize" filenames to prevent this. But, we've only seen it happen once, and are unable reproduce, so this is not urgent imho.

Please let us know if you see this again.

[0] https://docs.djangoproject.com/en/2.2/howto/custom-file-storage/#django.core.files.storage.get_available_name

[Launchpad Janitor (janitor)]

[Expired for Snap Store Server because there has been no activity for 60 days.]