Files replaced with same name + dimensions never regenerate

[josephlewisnz]

I've had an investigation and I believe this is due to the fact the variant remains the same and no hash check is done.

<source media="(max-width: 768px)" type="image/webp" srcset="$ScaleWidth(768).Format('webp').URL">

To Replicate

1. Upload a file with set dimensions
2. Using the "Replace the file" functionality upload a different image (same dimensions and name)
3. See front end still shows the "old" image

I will be investigating to see if there is a fix here, however, I also see a comment as to why the hash is not used, so maybe this is not possible and another approach is needed.

" * Stop caring about hash when checking for file collisions; This breaks many things.
* Specifically, the "original" image and the formatted image will have different hashes,
* but we cannot determine the formatted hash without generating it, or storing it somewhere. "

[tractorcow]

@josephlewisnz silverstripe image backend used to use the hash in all urls (even public image urls) but I believe in recent times the default has been changed to short urls sans-hash in the path for public images.

If you can re-configure your asset backend to route public images with hash you'll probably resolve the above issue.

It's all been rewritten since I have poked my head into the code (years ago haha), so unfortunately you may need to dig up and investigate the answer yourself.

[tractorcow]

yeah this is the new parser

https://github.com/silverstripe/silverstripe-assets/blob/2/src/FilenameParsing/NaturalFileIDHelper.php#L8

• Parsed Natural path URLs. Natural path is the same hashless path that appears in the CMS.

Reconfigure the public store to use this one instead and it'll probably fix it

https://github.com/silverstripe/silverstripe-assets/blob/2/src/FilenameParsing/HashFileIDHelper.php

• Parsed Hash path URLs. Hash paths group a file and its variant under a directory based on a hash generated from the
• content of the original file.

and config at

https://github.com/silverstripe/silverstripe-assets/blob/2/_config/asset.yml#L29-L33

best of luck

[josephlewisnz]

Thanks @tractorcow for the direction. I will update here if I make any progress!