* * * * *
                                        
       Oh, it's a bug on my side that prevents full conditional requests
                                        
I'm still pouring through web sever log files [1] and I'm noticing that many
of the feed readers fetching my various feeds files aren't using conditional
requests. I was in the process of writing to the author of one of them [2]
describing the oversight when I noticed that particular feed reader using
both methods of conditional requests: the If-Modified-Since: header and the
If-None-Match header in conjunction with a HEAD request. I thought I should
test that with my web server, just to make sure it was not a bug on my side.

It's a bug on my side [3]!

Specifically, an Apache bug where compressed output interferes with the If-
None-Match method. There is a workaround though:

-----[ Apache ]-----
RequestHeader edit "If-None-Match" '^"((.*)-gzip)"$' '"$1", "$2"'
-----[ END OF LINE ]-----

That rewrites the incoming If-None-Match header to work around the bug. Now
maybe that whole conditional request thang with my webserver will now work
properly.

Sigh.

[1] gopher://gopher.conman.org/0Phlog:2025/09/26.1
[2] https://artemis.jamesg.blog/bot
[3] https://flameeyes.blog/2017/08/22/apache-etag-and-not-modified/

Email Sean Conner at sean@conman.org

.