#2 is the only really viable option. If we have to put caching logic in 10 different places we'll screw it up 9 different times :).
On Tue, Sep 9, 2008 at 12:11 PM, John Hjelmstad <[EMAIL PROTECTED]> wrote: > As discussed on a few threads and tracked in JIRA issue ( > http://issues.apache.org/jira/browse/SHINDIG-579), we need to move > rewriting > logic out of AbstractHttpCache. Yet we should maintain rewritten content > caching capability. The question is where to put it. > I see two options, at a high level: > 1. In code that calls ContentRewriterRegistry.rewrite(HttpResponse|Gadget). > Eg. MakeRequestHandler, ProxyHandler, ViewContentFetcher, GadgetServer, and > the near-future Renderer and Preloader. This allows finer-grained control > over caching behavior in context, at the cost of distributing caching logic > in various places. > 2. In ContentRewriterRegistry.rewrite(HttpResponse|Gadget) itself, if so > chosen. Caching logic can be consolidated in > CachingContentRewriterRegistry, > for instance (which will no longer subclass CachingWebRetrievalFactory), > and > be considered an optimization to rewriting. > > I'm inclined to go #2. Rewriters themselves can be augmented with caching > hints if necessary, and be assumed deterministic for a given cache key in > the meantime. Consolidating rewriting logic makes it easier to share the > cache itself. > > Still, I might be missing situations in which additional context inherent > to > the calling context is needed to make a caching decision. > > --John >
