-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Geoff Davis wrote: > In testing all the new caching code, I ran into a fairly nasty IE bug: > > IE pays attention (more or less) to the Cache-Control header when it comes > to requesting new content from the server. The "more-or-less" part is > because IE 5.5+ introduces some proprietary Cache-Control tokens, > pre-check and post-check, that let IE ignore the headers to some extent (see > http://msdn.microsoft.com/workshop/author/perf/perftips.asp ). > Fortunately, this behavior can be turned off by setting Cache-Control: > pre-check=0, post-check=0 > > The problem is that after the page has been requested, IE doesn't > necessarily actually render it. If you have a page with a Last-Modified > tag, under some (all?) circumstances, IE will render what it has in cache > rather than what it has just requested. My guess is that there is a bug > in IE that causes its internal Last-Modified freshness heuristics to > override explicit Cache-Control freshness declarations and that it pulls > the cached page from the wrong place or at the wrong time. It was > difficult to track down, but straightforward to work around: I modified > CMFCore/CachingPolicyManager.py to allow you to disable the Last-Modified > header. To preserve backward compatibility, Last-Modified is on by > default, but you can now explicitly disable it. I have also added the > ability to set the pre-check and post-check tokens.
Thanks for the analysis, and the fix (sorry for the earlier, premature reply). > As an aside, a very useful tool for working with caching and IE is > Fiddler: http://www.fiddlertool.com/fiddler/ > It's basically the equivalent of LiveHTTPHeaders for IE. > > I am checking the fixes (with tests) into the 1.5 branch, and Sidnei has > volunteered to backport them to CMF 1.4. I *think* such a patch should apply cleanly to the trunk as well. Tres. - -- =================================================================== Tres Seaver +1 202-558-7113 [EMAIL PROTECTED] Palladion Software "Excellence by Design" http://palladion.com -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.5 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org iD8DBQFDOskJ+gerLs4ltQ4RAieeAKCvhbFD8SgeppjyqNSHliK/RWgzBACgguTW sP+pH39cbzoxSuH0S7+nAyE= =Zx3z -----END PGP SIGNATURE----- _______________________________________________ Zope-CMF maillist - Zope-CMF@lists.zope.org http://mail.zope.org/mailman/listinfo/zope-cmf See http://collector.zope.org/CMF for bug reports and feature requests