bug#526: Emacs 22, url package, problems with cache

bug#526: Emacs 22, url package, problems with cache

[Alexander Pohoyda]

The url-automatic-caching variable is nil by default, so cache is not written (even the cache directory is not created).  However, if I manually provide "If-Modified-Since" header in HTTP request and the server responds with "Not Modified 304", the cache file is expected to exists and is accessed -- which leads to error.

Possible solution -- before accessing the cache file, check whether it exists (url-is-cached).
Alternatively, do not expect a cache to exist if url-automatic-caching is set to nil.

-- 
Alexander Pohoyda <alexander.pohoyda@gmx.net>
PGP Key fingerprint:
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bug#526: Emacs 22, url package, problems with cache

[Magnus Henoch]

reassign 526 emacs,url
thanks

I keep meaning to clean up and fix various things in the url package,
but now I _definitely_ don't have time.  It would be nice if someone
else took a look at this.

Magnus

Processed: Re: bug#526: Emacs 22, url package, problems with cache

[Emacs bug Tracking System]

Processing commands for control@emacsbugs.donarmstrong.com:

> reassign 526 emacs,url
bug#526: Emacs 22, url package, problems with cache
Warning: Unknown package 'url'
bug reassigned from package `emacs' to `emacs,url'.

> thanks
Stopping processing here.

Please contact me if you need assistance.

Don Armstrong
(administrator, Emacs bugs database)

bug#526: Emacs 22, url package, problems with cache

[Julien Danjou]

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On Thu, Jul 03 2008, Alexander Pohoyda wrote:

> The url-automatic-caching variable is nil by default, so cache is not
> written (even the cache directory is not created). However, if I manually
> provide "If-Modified-Since" header in HTTP request and the server responds
> with "Not Modified 304", the cache file is expected to exists and is
> accessed -- which leads to error.
>
> Possible solution -- before accessing the cache file, check whether it exists (url-is-cached).
> Alternatively, do not expect a cache to exist if url-automatic-caching is set to nil.

I'm not sure this is really a bug after all. If you send a
"If-Modified-Since" header, you have to already own a copy of the
content. If what you propose is to return an empty buffer if there's no
cache, that does not seems like the good solution neither. And I would
not see the point to re-request the URL without the IMS header neither.

304 code is only returned if the client has done a conditional request,
which should be the case *only* if it has a cached copy. Otherwise it's
no sense.

-- 
Julien Danjou
❱ http://julien.danjou.info

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bug#526: Emacs 22, url package, problems with cache

[Lars Magne Ingebrigtsen]

"Alexander Pohoyda" <alexander.pohoyda@gmx.net> writes:

> However, if I manually provide "If-Modified-Since" header in HTTP
> request and the server responds with "Not Modified 304", the cache
> file is expected to exists and is accessed -- which leads to error.

I don't think this is a bug.  You've (manually) claimed to have a cached
copy of the item, and you don't -- so you should get an error, in my
opinion.

-- 
(domestic pets only, the antidote for overdose, milk.)
  bloggy blog http://lars.ingebrigtsen.no/