Re: Comments on draft-v10-03a.

Larry Masinter writes:
 > > Though I generally agree with what you're saying, there's a slight
 > > problem with this, I think.  If the first GET on a URL has side
 > > effects necessary to the semantics intended by the server, then it has
 > > to avoid being served from a cache.
 > 
 > How'd it get into the cache if it was never GET-ed in the first place?
 > Immaculate HTML?

Close.

Here are three ways I can think of:

1. A prior POST on the same URI as the subsequent GET can leave
something in a cache.

2. Any prior response that returned a Location header with the same URI
as the subsequent GET, in a 2xx response, can leave something in the
cache.

3. If the cache is a public cache, it might have been
another GET.  The side effect might be one that you want to cause the
first time a given *user* GETs a certain resource, not just the first time
anyone behind a cache requested it.

1. and 2. are extremely useful features, not bugs.

--Shel