Re:Re:Re: A question about "clientProcessExpired" function.

Thanks, Henrik pal!

You have clarified all my doubts.

George, Ma

----- Original Message -----
From: Henrik Nordstrom
To: maer727@sohu.com
Cc: squid-dev@squid-cache.org
Subject: Re:Re: A question about "clientProcessExpired" function.
Sent: Tue Apr 09 22:34:12 CST 2002

> Correct.
>
> And yes, there may be other more structured manners to do this than how it is
> currently done. The code in both client_side.c and peer_select.c is somewhat
> messy due to have been grown on for many years with new feature after new
> feature added. The processing of only-if-cached is one such feature simply
> added to the existing code where this was not originally thought of in the
> design.
>
> Regards
> Henrik
>
> maer727@sohu.com wrote:
> > Hi, Henrik pal!
> >
> > Thanks for your reply. I have known the aim of the function. But why should
> > we use such statements in this function? Such are my opinions:
> >
> > ///////////////////////////////////////////////////////////////////////////
> >/////////////////////////////////////// In file "client_side.c", line 355,
> > there are such statements,
> > if (clientOnlyIfCached(http)) {
> > clientProcessOnlyIfCachedMiss(http);
> > return;
> > }
> > ///////////////////////////////////////////////////////////////////////////
> >///////////////////////////////////////
> >
> > I think if "(clientOnlyIfCached(http))" returns true, it means the client
> > only want to get the object from cache. But the aim of the function is to
> > used for revalidation for expired objects. So if clients want to get object
> > only from cache, we should use "clientProcessOnlyIfCachedMiss(http)" to
> > retuen an error. (Since the object is out of date.)
> >
> > Am I correct? :-)
> >
> > Best regards,
> > Geoege, Ma
> >
> > ----- Original Message -----
> > From: Henrik Nordstrom
> > To: maer727@sohu.com ;squid-dev@squid-cache.org
> > Cc: squid-dev@squid-cache.org
> > Subject: Re: A question about "clientProcessExpired" function.
> > Sent: Tue Apr 09 17:05:54 CST 2002
> >
> > > On Tuesday 09 April 2002 06:03, maer727@sohu.com wrote:
> > > > 1. After reading for several times, I can not find the goal the
> > > > function "clientProcessExpired". What is it used for?
> > >
> > > Processing of requests where the cached entry has expired and needs
> > > to be revalidated before given to the user.
> > >
> > > > 2. In file "client_side.c", line 355, there are such statements,
> > > > if (clientOnlyIfCached(http)) {
> > > > clientProcessOnlyIfCachedMiss(http);
> > > > return;
> > > > }
> > > >
> > > > I think the "clientOnlyIfCached" is used to check whether an object
> > > > coule be taken from cache. "clientProcessOnlyIfCachedMiss" is used
> > > > to return an error when the specific object is not in cache. But I
> > > > think the above four lines of the statements do not conform the
> > > > following comments.
> > >
> > > clientOnlyIfCached checks if the client requested to have the object
> > > only satisfied from cache, disallowing any network retreivals.
> > >
> > > See the meaning of "Cache-control: only-if-cached" in RFC2616.
> > >
> > > > The comments are,
> > > > /*
> > > > * check if we are allowed to contact other servers
> > > > * @?@: Instead of a 504 (Gateway Timeout) reply, we may want
> > > > to return * a stale entry *if* it matches client requirements
> > > > */
> > >
> > > Yes. This looks correct.
> > >
> > > Regards
> > > Henrik
Received on Tue Apr 09 2002 - 20:44:00 MDT