RachelByTheBay has been testing feed readers for conformance to HTTP semantics and general good behavior. To participate, she asks that feed reader maintainers reach out.
I request BazQux do so. It’d be nice to know the reader I use is well-behaved towards sites I subscribe to.
Rachel has identified one issue with BazQux If-None-Match, just by watching normal subscribers to her feed. But that cannot provide comprehensive validation.
I have reached out for more details.
I can only see that this could happen if “Not Modified” was received or the feed content had the same hash. In both cases I don’t update the URL data at all and use the same If-None-Match / If-Modified-Since as before.
This might not be ideal, but should work fine with correctly configured sites. And if the site is badly configured (and many sites are), I would rather get extra full downloads than miss the update.
If-None-Match contains a hash. If it has changed but the hash of the feed content has not, it means the site is badly configured.