[Zope] how to invalidate an object in the cache?

[Marco Mariani]

I am working with photo rotating/resizing, via PIL on external
method.

All the images are kept on LocalFS.

There is a thumbnail bonanza page, when I select a thumbnail a
form is shown, and I can adjust rotation/contrast/brightness.
Upon submit, the new image+thumbnail is calculated and written
to the filesystem.

Then the method calls RESPONSE.redirect to show the index page again.

When I go back to the index thumbnail page, the
image I've just rotated is displayed with the right size (which means
that Zope gets it right), but not rotated (which means that Netscape
reads the old image from the cache). I mean, if it was 320x200 and is
now 200x320, the browser displays the old 320x200 image stretched to
200x320.

I'm not digging into contrast and brightness, but the same happens.

Is there a way to force the browser to discard the cache for that
image? If I go "right-button, view image, shift+reload" the new
image is displayed.

Any idea? I'm not very knowledgeable on this matter, I don't design
pages for a living.

Might javascript help?


Thank you.

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