Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:81620
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: softfail (pb1.pair.com: domain tekwire.net does not designate 212.27.42.2 as permitted sender)
Reply-To: <francois@tekwire.net>
To: "'Rasmus Lerdorf'" <rasmus@lerdorf.com>,
	<internals@lists.php.net>
References: <008b01d03f06$bc8e9940$35abcbc0$@tekwire.net> <54CFAAA5.6050700@lerdorf.com>
In-Reply-To: <54CFAAA5.6050700@lerdorf.com>
Date: Mon, 2 Feb 2015 18:31:11 +0100
Message-ID: <00ac01d03f0e$09a0ce90$1ce26bb0$@tekwire.net>
MIME-Version: 1.0
Content-Type: text/plain;
	charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Thread-Index: AQFX7Xg2OtZN3lyuxp3N4vgO3eqARwHgw/C+nb8y2vA=
Content-Language: fr
Subject: RE: [PHP-DEV] [VOTE] Add is_cacheable() stream-wrapper operation
From: francois@tekwire.net (=?iso-8859-1?Q?Fran=E7ois_Laupretre?=)

> De=A0: Rasmus Lerdorf [mailto:rasmus@lerdorf.com]
> Doesn't this imply that "path" is the one true cache key? There are =
some
> issues with that which we will have to address at some point. For
> example, when running fpm chrooted you need more than the path. We'll
> likely need a more APC-like option here to use the device+inode for =
the
> key. It seems like a generic mechanism like you are proposing needs to
> take this into account and provide some mechanism that tells the =
opcode
> cache how to determine uniqueness. Perhaps that is simply encoded into
> the path parameter, but then maybe it should have a more appropriate
> name.

Yes, it implies that the path is the cache key. It implies that the =
stream
wrapper has a way to build unique and reproducible paths (PHK, for =
instance,
builds a unique ID from (dev/inode/mtime) when opening a package and =
builds
its paths from this ID).

My first idea was to add a 'cache_key' element in the stream_stat() =
result.
This element would be a binary string to use as key. This way, the =
stream
wrapper can return a path, a dev/inode/mtime concatenation, etc. If we =
don't
want to modify the stat() result, we can define a 'cache_key' hook in
php_stream_wrapper_ops.

I reverted to a system where path is considered as unique because I =
thought
my original idea would be considered as too complex. And using the path =
as
key was enough for phar and phk. But I agree, it is not a good solution =
for
'file:', which should be cached  by dev/inode/mtime.

I put the vote in standby.

Cheers

Fran=E7ois