Github user rainerjung commented on the issue:
https://github.com/apache/tomcat/pull/115
Note that although the RFC demands to handle an invalid Expires header
(like Expires: 0) like one with a timestamp in the past, I coincidentally ran
into a problem yesterday, where the Apache web server with mod_cache only
complies to this in the default case. By default in both cases content is not
cached. But in the case of a valif timestamp in the past, more rules apply,
like being able to force caching by configuration and also evaluating
Cache-Control max-age and s-maxage. In the invalid Expires value case, the
decision to not cache currently happens unconditionally.
I applied a patch to the trunk of the Apache web server yesterday and
proposed it for 2.4, but it might serve as an example, why an explicit
timestamp in the past might be slightly more robust (while being a bit more
expensive) then just "Expires: 0" or any other invalid value.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]