-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Martin Aspeli wrote: > Laurence Rowe wrote: >> 2009/12/31 Martin Aspeli<optilude+li...@gmail.com>: >>> Hi, >>> >>> A few of us are playing with some caching tools, trying to get to a more >>> sane and less monkey patch-laden approach than CacheFu >>> (Products.CacheSetup), for use with Zope 2.12. >>> >>> It is relatively easy to set response headers, e.g. in an >>> IPubBeforeCommit event handler. >>> >>> However, we also need to be able to intercept a request to send a 304 >>> response if the underlying object has not been modified. >>> >>> CacheFu monkey patches ZPT rendering to avoid the actual rendering if a >>> 304 response is being sent, returning an empty string instead. I'd >>> rather not have such patches, though, and anyway this only work with >>> things rendered as ZPTs. It also doesn't avoid any pre-work that a view >>> may do before rendering its template, if indeed it has one. >>> >>> Another thought was to use IPubAfterTraversal, at which point we have >>> the object to publish and security checks have been completed. However, >>> ZPublisher.Publish goes straight from that into mapply(). >>> >>> Can anyone think of a good way to do this? Maybe we need to add some >>> kind of condition around mapply(), e.g. to do not nothing if there's a >>> 304 response header, or some other marker? >> I think this is analogous to 404 Not Found errors. It should be >> possible to handle them with the combination of: >> >> * raise a NotModified exception in an IPubAfterTraversal handler >> * in a NotModified exception view, setStatus 304 Not Modified an >> return an empty string. > > Yep, I actually got there in the end on my own. The way that the > exception *type/class name* is used to determine the status is pretty > evil,
bobo was trying really hard back in 1996. ;) > but so long as the exception is actually called NotModified, it > works. Setting it explicitly doesn't, since it gets overridden. You can "lock" the status and body of the response, which causes subsequent attempts to set them to fail silently. Tres. - -- =================================================================== Tres Seaver +1 540-429-0999 tsea...@palladion.com Palladion Software "Excellence by Design" http://palladion.com -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAktEURoACgkQ+gerLs4ltQ6RxQCgm1F5fZCEVo7e3HWknAN8FyLB pXkAnA+7pUvamS2SAaKnARI5LYRXcGem =p7ah -----END PGP SIGNATURE----- _______________________________________________ Zope-Dev maillist - Zope-Dev@zope.org https://mail.zope.org/mailman/listinfo/zope-dev ** No cross posts or HTML encoding! ** (Related lists - https://mail.zope.org/mailman/listinfo/zope-announce https://mail.zope.org/mailman/listinfo/zope )
