Clear Image Cache Without Clearing Browser Cache [#2424695]

When you update an image style, you need to clear your browser cache in order to see the updated image style take effect. There may be cases that you need to update the image ASAP and you can't rely on users clearing their browser cache.

Steps to reproduce:

View Image in Safari
Look at the image url: /sites/default/files/styles/river_thumbnails_teaser/public/field/image/my_image.jpg?itok=U5XXDilb
In Chrome log in and update the image style
Make sure to press the "Update Style" button
Flush All Cache
Refresh the page in Safari
Look at the image url: /sites/default/files/styles/river_thumbnails_teaser/public/field/image/my_image.jpg?itok=U5XXDilb

The only way I can see the image take in effect right away is the clear my browser cache.

Do you think it would be a good idea to update the itok parameter value every time an image style is updated?

Comments

Comment #1

elijah lynn

Portland, Oregon

commented 23 March 2016 at 21:18

Just ran into this issue because we are using Upload Replace module that will rename the new uploaded file to be the same name. The itok is generated with image_style_path_token() and will always generate the same token and the code in image_style_deliver() will always check the itok with the same algorithm for incoming image derivative generation requests.

So the logical option of having the itok param change is not that realistic and it would appear that the only option if we are using the same file name is to use Cache-control headers and pass a no-store along to the browser for those images.

Or maybe add a second query param onto the image to bust the cache...

Comment #2

elijah lynn

Portland, Oregon

commented 23 March 2016 at 21:22

Comment #3

23 March 2016 at 21:22

Version:

7.34

» 7.x-dev

Core issues are now filed against the dev versions where changes will be made. Document the specific release you are using in your issue comment. More information about choosing a version.