Graham Leggett wrote: > Hi Brian, > > You mentioned at Apachecon that one of the things you needed from the > server (and built) was an offline module. > > Thinking about it, in order to achieve the goal of a cache mimicking an > origin server, is the following true: > > - Cache-Control and Pragma headers must be stripped from requests into > the cache.
Why? Just because you are in offline mode doesn't mean other proxies between you and the client (or the client itself) are. > > - mod_cache must, if the backend response is 5xx, deliver the latest > cached data the server has present, regardless of whether the cached > entry is stale or not. I worked on an offline implementation recently. I only delivered the cached response regardless of staleness (and, indeed, all other checks beyond its existence), on a 502/504. My logic was that those are the only codes being generated by the "client" end of the server (eg, mod_proxy), and anything else could be considered a fresh response. I think I can get permission to send a patch of what we did so far, if there's interest; it's crude and still not fully tested (and we haven't merged in the recent mod_disk_cache changes), but it's simple and may be a helpful starting point. > > Is there anything else it would need to do? > > Regards, > Graham > --
