cocoon-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Grzegorz Kossakowski (JIRA)" <j...@apache.org>
Subject [jira] Commented: (COCOON-2044) servlet: protocol URIs have to be globally unique for use as cache-keys
Date Wed, 18 Apr 2007 14:27:15 GMT

    [ https://issues.apache.org/jira/browse/COCOON-2044?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12489753
] 

Grzegorz Kossakowski commented on COCOON-2044:
----------------------------------------------

I'm not so sure how XSLT processor handles URIs inside stylesheets. While I was testing caching
of ServletSource I remember that I've encountered XSLT processor's weirdnesses but did not
dig into this any further. Could you find out (I mean: check the code) what are the current
limitations of XSLT URI handling? This knowledge would be very useful not only while dealing
with this very issue.

I ask for it, because I really don't like adding any additional parameter. Even more I don't
like identityHashCode() hack ;)
What's more, I think you address the issue wrong way because your proposed change makes URI
unique but only by including information about the entity asking for the resource what breaks
another contract.
This way, if servlet A and B ask servlet C for *exactly* the same resource X we would end
up with two different cache entries:
X?servlet-services-id=identityHashCode(A)
X?servlet-services-id=identityHashCode(A)
instead of one:
X?servlet-services-id=identityHashCode(C)

In ServletSource constructor there is ServletConnection available that in turn has the access
for all needed properties. Even more, there is FIXME mark already related to this:
        // FIXME: This will not be a system global id, as the blockName is block local.
        String ssp = (new URI(this.blockName, null, path, queryString, null)).toString();

What do you think, now? Are you willing to provide a patch for this?

> servlet: protocol URIs have to be globally unique for use as cache-keys
> -----------------------------------------------------------------------
>
>                 Key: COCOON-2044
>                 URL: https://issues.apache.org/jira/browse/COCOON-2044
>             Project: Cocoon
>          Issue Type: Bug
>          Components: - Servlet service framework
>    Affects Versions: 2.2-dev (Current SVN)
>            Reporter: Alexander Klimetschek
>         Assigned To: Grzegorz Kossakowski
>            Priority: Critical
>
> All servlet protocol URIs like servlet:/some/thing or servlet:super:/foo/bar or servlet:myblock:/another/path
have to be globally unique because they are used in the cache, of which there is only one
global with globally acting keys.
> There are two caches in standard Cocoon configuration (the only ones I know of ;-), both
with a different key generation. Here are ideas how to make the keys global:
> a) EHDefaultStore for caching resources of caching pipelines: they use the uriPrefix
of the Enviroment in the key, so providing a uriPrefix (eg. the mount path of the servlet)
works here.
> b) DefaultTransientStore which caches XSLT and JX generator sources (don't know why this
is different from a)): they do not use the uriPrefix and much worse, they need correct URIs
because they are read by the XSLT processor, who does not like things like servlet:uniqueID34:/xsl/stylesheet.xsl
containing arbitrary schemes at the beginning. Appending an ID via a query parameter seems
the only working solution (tried it already): servlet:/xsl/stylesheet.xsl?servlet-services-id=12345
> Another solution would be to have one cache per sitemap, so that the keys don't have
to be unique anymore. But I don't know how to configure that and if this is feasible.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


Mime
View raw message