Re: ServerPageAction: XMLFragment reuse in XSL transformer
Sorry for the delay!
Thanks for your answer, Peter.
I must admit that I did not compare the performance
between the aggregation and the transformer approach. The aggregation is just
one additional component in the pipeline, that has to process the big document.
Apart from that the necessarykind of processing of the big document
requires the XSL-transformer to build an entire DOMDocument before doing the
transformations, I guess.
So what I have done is I have written a Transformer
for handling expandable data like the directory tree in the Windows' Explorer.
It requires all input elements to have a unique id attribute. According to the
tree status stored in the session, the transformer will only forward the visible
tags and drop everything else. It also supports URL commands for setting
upthe status tree (only root element is visible or all parent elements of
one particular one are visible),expanding and collapsing child elements.
Later transformers can then easily do thepresentation of the visible part
of the tree and setup URL links e.g. for expanding leaf nodes
futhermore.
In most cases all SAX processing is done on-the-fly
without intermediate storage of all SAX element.
The quality of the code is probably not very high,
as I am not working with Cocoon for very long, but at least its documented. Do
you think this transformer could be useful for other people? And do you know to
whom I should give it?
Thank you and best regards,
Christian
- Original Message -
From:
Hunsberger, Peter
To: '[EMAIL PROTECTED]'
Sent: Monday, October 21, 2002 2:56
PM
Subject: RE: ServerPageAction:
XMLFragment reuse in XSL transformer
That
should work. I don't know ifit is much (any?) more efficient
thanusing aggregation...
-Original Message-From: Christian Kurz
[mailto:[EMAIL PROTECTED]]Sent: Saturday, October 19, 2002 4:53
AMTo: [EMAIL PROTECTED]Subject:
Re: ServerPageAction: XMLFragment reuse in XSL
transformer
I'll try to implement a pipeline similar to
this:
FileGenerator -
"MyFilterTransformer" - other steps
The FileGenerator will read the big document
and is cacheable.
MyFilterTransformer will use the XMLFragment
from the session to forward only a small portion of the events from the
generator, following your idea. MyFilterTransformer is the first component
in the pipeline, which is NOT cacheable, as it returns different data on
every request.
To my understanding cocoon's caching strategy
should cache the pipeline as far as possible. In this particular case only
including the FileGenerator:
"The keys of all cacheable components are
chained, and together they build the cache key. The request is processed,
and the document is built. The cache stores the result of the _last_
component, indicating cacheablility. The next time this document is
requested, the key is built, and the cached content is fetched from the
cache.
Next, the cache asks all components of the
event pipeline, if their input has changed since the time the content was
cached. For example, the generator checks this by looking at the last
modification date of the xml document, the xslt transformer checksthe
date of the stylesheet, and so on. Only if all state that the content is
still valid it is used from the cache. Otherwise, the document is generated
from scratch. So the event pipeline tries to cache as much of the XML
processing pipeline as possible."
from New Riders, Cocoon: Building XML
Applications by Matthew Langham and Carsten Ziegeler, p. 182.
- Original Message -
From:
Hunsberger, Peter
To: '[EMAIL PROTECTED]'
Sent: Friday, October 18, 2002 4:23
PM
Subject: RE: ServerPageAction:
XMLFragment reuse in XSL transformer
Well, obviously, it something changes on every request then, by
definition, it isn't cacheable. However, I believe, with
aggregation, only the components that are marked as invalidated in the
cache are rebuilt on a new request; the rest of the data stays in it's
respective cache. This does mean that the aggregated document
is rebuilt each time (I have no idea what the impact of that would
be). But the "large" document source would stay not be retrieved
from scratch.
Perhaps using the document function as Olivier would avoid
this. At one point document did notcheck cache validity at all
and you would only get a newer version of the data if the main data was
invalidated in cache. I think this has been fixed in 2.0.3. The
problem is how to get the URI resolve for the document function to fund
the data in session. Someone else will have to tell you how to do
Re: ServerPageAction: XMLFragment reuse in XSL transformer
Salut Olivier,
thank you for your help! That sounds like a quick and easy solution. I'd
just need to use url-encoded session-ids to pass the session id to the
cocoon:/ request and in order to do so, I need to get it from the request
object. I'll see whether this is easily possible.
Thanks,
Christian
- Original Message -
From: ROSSEL Olivier [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Sent: Friday, October 18, 2002 8:49 AM
Subject: RE: ServerPageAction: XMLFragment reuse in XSL transformer
May be you can try to import a XML fragment via the document() XSL
function.
Calling a cocoon:/ URL, you will get the XML fragment in a variable inside
your XSL.
Neat and very efficient !!!
-Message d'origine-
De: Christian Kurz [mailto:crkurz;gmx.de]
Date: vendredi 18 octobre 2002 08:42
À: [EMAIL PROTECTED]
Objet: Re: ServerPageAction: XMLFragment reuse in XSL transformer
Thank you very much for the quick feed-back! The idea sounds great and is
a
lot cleaner, than fiddling something in some XSL extension.
I am not sure about the cachaebility: the XMLFragment specifying, which
nodes to filter from the big input document, changes everytime, so Cocoon
would need to parse the source file on every request (, if my
understanding
is right).
If I'd slidely change your approach to implementing the same approach into
a
transformer component. This transformer component will not be cacheable,
but
at least the generator in front of it would be.
Thanks again,
Christian
BTW, thanks also for the code snippet. It helps a lot, as soon as it comes
to thinks like the ObjectModel, I start feeling uncomfortable.
- Original Message -
From: Hunsberger, Peter mailto:Peter.Hunsberger;stjude.org
To: '[EMAIL PROTECTED]' mailto:'[EMAIL PROTECTED]'
Sent: Thursday, October 17, 2002 6:46 PM
Subject: RE: ServerPageAction: XMLFragment reuse in XSL transformer
There's probably about half a dozen ways to do this. Perhaps one of the
simplest is just to create your own caching generator and use aggregation
(with any other XML you may need) in the pipeline.
In the generator you'll need to implement the setup method to see the
objectModel, something like the following:
private gunk mySessionData = null;
public void setup( SourceResolver resolver, Map objectModel, String src,
Parameters parms )
throws ProcessingException, SAXException, IOException
{
if (mySessionData == null ) {
super.setup( resolver, objectModel, src, parms );
Request request =
(Request)ObjectModelHelper.getRequest(objectModel);
Session session = request.getSession(false);
if (session != null) {
// save a pointer to your session data for use in the generate
method
mySessionData =
}
}
}
Now in your generate method just pick up whatever data hangs off of
mySessionData and away you go
-Original Message-
From: Christian Kurz [mailto:crkurz;gmx.de]
Sent: Thursday, October 17, 2002 11:26 AM
To: [EMAIL PROTECTED]
Subject: ServerPageAction: XMLFragment reuse in XSL transformer
Hello cocoon-users,
I need to generate some tiny XML elements (XMLFragment) within a
ServerPageAction and I would like to use this XMLFragment later on in an
XSL
transformer, that is fed by an xml generator. The XMLFragment captured in
the ServerPageAction is basically saying, which nodes are to be returned
from the big input document.
From some other message in this group I have understood, that passing
objects is only possible through session or request objects, but not
through
sitemap variables. I don't like to use a request generator as the starting
point of the pipeline, as I'd loose cacheability at a very early step in
the
pipeline. With a quite big xml input document, this does not seem a good
idea to me.
So I am currently struggling how to get a piece of XML, that is attached
to
a session or request object, into the xsl transformer. Has anybody tried
this before e.g. using an XSL extension?
Any help or hints appreciated!
Thank you in advance,
Christian
This e-mail is intended only for the above addressee. It may contain
privileged information. If you are not the addressee you must not copy,
distribute, disclose or use any of the information in it. If you have
received it in error please delete it and immediately notify the sender.
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Please check that your question has not already been answered in the
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To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail
Re: ServerPageAction: XMLFragment reuse in XSL transformer
I'll try to implement a pipeline similar to
this:
FileGenerator -
"MyFilterTransformer" - other steps
The FileGenerator will read the big document and
is cacheable.
MyFilterTransformer will use the XMLFragment from
the session to forward only a small portion of the events from the generator,
following your idea. MyFilterTransformer is the first component in the pipeline,
which is NOT cacheable, as it returns different data on every
request.
To my understanding cocoon's caching strategy
should cache the pipeline as far as possible. In this particular case only
including the FileGenerator:
"The keys of all cacheable components are
chained, and together they build the cache key. The request is processed, and
the document is built. The cache stores the result of the _last_ component,
indicating cacheablility. The next time this document is requested, the key is
built, and the cached content is fetched from the cache.
Next, the cache asks all components of the event
pipeline, if their input has changed since the time the content was cached. For
example, the generator checks this by looking at the last modification date of
the xml document, the xslt transformer checksthe date of the stylesheet,
and so on. Only if all state that the content is still valid it is used from the
cache. Otherwise, the document is generated from scratch. So the event pipeline
tries to cache as much of the XML processing pipeline as possible."
from New Riders, Cocoon: Building XML
Applications by Matthew Langham and Carsten Ziegeler, p. 182.
- Original Message -
From:
Hunsberger, Peter
To: '[EMAIL PROTECTED]'
Sent: Friday, October 18, 2002 4:23
PM
Subject: RE: ServerPageAction:
XMLFragment reuse in XSL transformer
Well, obviously, it something changes on every request then, by
definition, it isn't cacheable. However, I believe, with aggregation,
only the components that are marked as invalidated in the cache are rebuilt on
a new request; the rest of the data stays in it's respective
cache. This does mean that the aggregated document is rebuilt each
time (I have no idea what the impact of that would be). But the "large"
document source would stay not be retrieved from scratch.
Perhaps using the document function as Olivier would avoid this.
At one point document did notcheck cache validity at all and you would
only get a newer version of the data if the main data was invalidated in
cache. I think this has been fixed in 2.0.3. The problem is how to get
the URI resolve for the document function to fund the data in session.
Someone else will have to tell you how to do that (and if it's even
possible)...
-Original
Message-From: Christian Kurz
[mailto:[EMAIL PROTECTED]]Sent: Friday, October 18, 2002 1:42
AMTo: [EMAIL PROTECTED]Subject: Re:
ServerPageAction: XMLFragment reuse in XSL transformer
Thank you very much for the quick feed-back!
The idea sounds great and is a lot cleaner,
than fiddling something in someXSL extension.
I am not sure about the cachaebility: the
XMLFragment specifying, which nodes to filter from the big input document,
changes everytime, so Cocoon would need to parse the source file on every
request (, if my understanding is right).
If I'd slidely change your approach to
implementing the same approach into a transformer component. This
transformer component will not be cacheable, but at least the generator in
front of it would be.
Thanks again,
Christian
BTW, thanks also for the code snippet. It helps
a lot, as soon as it comes to thinks like the ObjectModel, I start feeling
uncomfortable.
- Original Message -
From:
Hunsberger, Peter
To: '[EMAIL PROTECTED]'
Sent: Thursday, October 17, 2002 6:46
PM
Subject: RE: ServerPageAction:
XMLFragment reuse in XSL transformer
There's probably about half a dozen ways to do this. Perhaps
one of the simplest is just to create your own caching generator and use
aggregation (with any other XML you may need)in the
pipeline.
In the generator you'll need to implement the setup method to see
the objectModel, something like the following:
private gunk mySessionData = null;
public void setup( SourceResolver resolver, Map objectModel, String
src, Parameters parms ) throws
ProcessingException, SAXException,
IOException {
if (mySessionData == null )
{
super.setup(
resolver, objectModel, src, parms );
Request
request =
(Request)ObjectModelHelper.getRequest(objectModel);
Session session =
request.getSession(false);
if (session != null) {
// save a pointer to your sessio
Re: ServerPageAction: XMLFragment reuse in XSL transformer
Thank you very much for the quick feed-back!
The idea sounds great and is a lot cleaner, than
fiddling something in someXSL extension.
I am not sure about the cachaebility: the
XMLFragment specifying, which nodes to filter from the big input document,
changes everytime, so Cocoon would need to parse the source file on every
request (, if my understanding is right).
If I'd slidely change your approach to implementing
the same approach into a transformer component. This transformer component will
not be cacheable, but at least the generator in front of it would
be.
Thanks again,
Christian
BTW, thanks also for the code snippet. It helps a
lot, as soon as it comes to thinks like the ObjectModel, I start feeling
uncomfortable.
- Original Message -
From:
Hunsberger, Peter
To: '[EMAIL PROTECTED]'
Sent: Thursday, October 17, 2002 6:46
PM
Subject: RE: ServerPageAction:
XMLFragment reuse in XSL transformer
There's probably about half a dozen ways to do this. Perhaps one
of the simplest is just to create your own caching generator and use
aggregation (with any other XML you may need)in the
pipeline.
In
the generator you'll need to implement the setup method to see the
objectModel, something like the following:
private gunk mySessionData = null;
public void setup( SourceResolver resolver, Map objectModel, String
src, Parameters parms ) throws
ProcessingException, SAXException,
IOException {
if (mySessionData == null )
{
super.setup(
resolver, objectModel, src, parms );
Request request
=
(Request)ObjectModelHelper.getRequest(objectModel);
Session session =
request.getSession(false);
if (session != null) {
//
save a pointer to your session data for use in the generate
method
mySessionData =
}
} }
Now
in your generate method just pick up whatever data hangs off of
"mySessionData" and away you go
-Original Message-From:
Christian Kurz [mailto:[EMAIL PROTECTED]]Sent: Thursday, October 17,
2002 11:26 AMTo: [EMAIL PROTECTED]Subject:
ServerPageAction: XMLFragment reuse in XSL transformerHello cocoon-users,
I need to generate some tiny XML elements
(XMLFragment) within a ServerPageAction and I would like to use this
XMLFragment later on in an XSL transformer, that is fed by an xml generator.
The XMLFragment captured in the ServerPageAction is
basically saying, which nodes are to be returned from the big input
document.
From some other message in this group I have
understood, that passing objects is only possible through session or request
objects, but not through sitemap variables. I don't like to use a request
generator as the starting point of the pipeline, as I'd loose cacheability
at a very early step in the pipeline.With a quite bigxml input
document,this does not seem a good idea to me.
So I am currently struggling how to get a piece
of XML, that isattached to a session or request object, into the xsl
transformer. Has anybody tried this before e.g. using an XSL
extension?
Any help or hints appreciated!
Thank you in advance,
Christian
RE: ServerPageAction: XMLFragment reuse in XSL transformer
May be you can try to import a XML fragment via the document() XSL function.
Calling a cocoon:/ URL, you will get the XML fragment in a variable inside
your XSL.
Neat and very efficient !!!
-Message d'origine-
De: Christian Kurz [mailto:crkurz;gmx.de]
Date: vendredi 18 octobre 2002 08:42
À: [EMAIL PROTECTED]
Objet: Re: ServerPageAction: XMLFragment reuse in XSL transformer
Thank you very much for the quick feed-back! The idea sounds great and is a
lot cleaner, than fiddling something in some XSL extension.
I am not sure about the cachaebility: the XMLFragment specifying, which
nodes to filter from the big input document, changes everytime, so Cocoon
would need to parse the source file on every request (, if my understanding
is right).
If I'd slidely change your approach to implementing the same approach into a
transformer component. This transformer component will not be cacheable, but
at least the generator in front of it would be.
Thanks again,
Christian
BTW, thanks also for the code snippet. It helps a lot, as soon as it comes
to thinks like the ObjectModel, I start feeling uncomfortable.
- Original Message -
From: Hunsberger, Peter mailto:Peter.Hunsberger;stjude.org
To: '[EMAIL PROTECTED]' mailto:'[EMAIL PROTECTED]'
Sent: Thursday, October 17, 2002 6:46 PM
Subject: RE: ServerPageAction: XMLFragment reuse in XSL transformer
There's probably about half a dozen ways to do this. Perhaps one of the
simplest is just to create your own caching generator and use aggregation
(with any other XML you may need) in the pipeline.
In the generator you'll need to implement the setup method to see the
objectModel, something like the following:
private gunk mySessionData = null;
public void setup( SourceResolver resolver, Map objectModel, String src,
Parameters parms )
throws ProcessingException, SAXException, IOException
{
if (mySessionData == null ) {
super.setup( resolver, objectModel, src, parms );
Request request =
(Request)ObjectModelHelper.getRequest(objectModel);
Session session = request.getSession(false);
if (session != null) {
// save a pointer to your session data for use in the generate
method
mySessionData =
}
}
}
Now in your generate method just pick up whatever data hangs off of
mySessionData and away you go
-Original Message-
From: Christian Kurz [mailto:crkurz;gmx.de]
Sent: Thursday, October 17, 2002 11:26 AM
To: [EMAIL PROTECTED]
Subject: ServerPageAction: XMLFragment reuse in XSL transformer
Hello cocoon-users,
I need to generate some tiny XML elements (XMLFragment) within a
ServerPageAction and I would like to use this XMLFragment later on in an XSL
transformer, that is fed by an xml generator. The XMLFragment captured in
the ServerPageAction is basically saying, which nodes are to be returned
from the big input document.
From some other message in this group I have understood, that passing
objects is only possible through session or request objects, but not through
sitemap variables. I don't like to use a request generator as the starting
point of the pipeline, as I'd loose cacheability at a very early step in the
pipeline. With a quite big xml input document, this does not seem a good
idea to me.
So I am currently struggling how to get a piece of XML, that is attached to
a session or request object, into the xsl transformer. Has anybody tried
this before e.g. using an XSL extension?
Any help or hints appreciated!
Thank you in advance,
Christian
This e-mail is intended only for the above addressee. It may contain
privileged information. If you are not the addressee you must not copy,
distribute, disclose or use any of the information in it. If you have
received it in error please delete it and immediately notify the sender.
Security Notice: all e-mail, sent to or from this address, may be
accessed by someone other than the recipient, for system management and
security reasons. This access is controlled under Regulation of
Investigatory Powers Act 2000, Lawful Business Practises.
-
Please check that your question has not already been answered in the
FAQ before posting. http://xml.apache.org/cocoon/faq/index.html
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
RE: ServerPageAction: XMLFragment reuse in XSL transformer
There's probably about half a dozen ways to do this. Perhaps one of
the simplest is just to create your own caching generator and use aggregation
(with any other XML you may need)in the pipeline.
In the
generator you'll need to implement the setup method to see the objectModel,
something like the following:
private gunk mySessionData = null;
public
void setup( SourceResolver resolver, Map objectModel, String src, Parameters
parms ) throws ProcessingException,
SAXException, IOException {
if (mySessionData == null )
{
super.setup(
resolver, objectModel, src, parms );
Request request =
(Request)ObjectModelHelper.getRequest(objectModel);
Session session =
request.getSession(false);
if (session != null) {
//
save a pointer to your session data for use in the generate
method
mySessionData =
}
} }
Now in
your generate method just pick up whatever data hangs off of "mySessionData" and
away you go
-Original Message-From:
Christian Kurz [mailto:[EMAIL PROTECTED]]Sent: Thursday, October 17, 2002
11:26 AMTo: [EMAIL PROTECTED]Subject:
ServerPageAction: XMLFragment reuse in XSL transformerHello cocoon-users,
I need to generate some tiny XML elements
(XMLFragment) within a ServerPageAction and I would like to use this
XMLFragment later on in an XSL transformer, that is fed by an xml generator.
The XMLFragment captured in the ServerPageAction is
basically saying, which nodes are to be returned from the big input
document.
From some other message in this group I have
understood, that passing objects is only possible through session or request
objects, but not through sitemap variables. I don't like to use a request
generator as the starting point of the pipeline, as I'd loose cacheability at
a very early step in the pipeline.With a quite bigxml input
document,this does not seem a good idea to me.
So I am currently struggling how to get a piece
of XML, that isattached to a session or request object, into the xsl
transformer. Has anybody tried this before e.g. using an XSL
extension?
Any help or hints appreciated!
Thank you in advance,
Christian
RE: ServerPageAction: XMLFragment reuse in XSL transformer
Well,
obviously, it something changes on every request then, by definition, it isn't
cacheable. However, I believe, with aggregation, only the components that
are marked as invalidated in the cache are rebuilt on a new request; the rest of
the data stays in it's respective cache. This does mean that the
aggregated document is rebuilt each time (I have no idea what the impact of that
would be). But the "large" document source would stay not be retrieved
from scratch.
Perhaps using the document function as Olivier would avoid this. At
one point document did notcheck cache validity at all and you would only
get a newer version of the data if the main data was invalidated in cache. I
think this has been fixed in 2.0.3. The problem is how to get the URI
resolve for the document function to fund the data in session. Someone
else will have to tell you how to do that (and if it's even
possible)...
-Original
Message-From: Christian Kurz
[mailto:[EMAIL PROTECTED]]Sent: Friday, October 18, 2002 1:42
AMTo: [EMAIL PROTECTED]Subject: Re:
ServerPageAction: XMLFragment reuse in XSL transformer
Thank you very much for the quick feed-back!
The idea sounds great and is a lot cleaner,
than fiddling something in someXSL extension.
I am not sure about the cachaebility: the
XMLFragment specifying, which nodes to filter from the big input document,
changes everytime, so Cocoon would need to parse the source file on every
request (, if my understanding is right).
If I'd slidely change your approach to
implementing the same approach into a transformer component. This transformer
component will not be cacheable, but at least the generator in front of it
would be.
Thanks again,
Christian
BTW, thanks also for the code snippet. It helps a
lot, as soon as it comes to thinks like the ObjectModel, I start feeling
uncomfortable.
- Original Message -
From:
Hunsberger, Peter
To: '[EMAIL PROTECTED]'
Sent: Thursday, October 17, 2002 6:46
PM
Subject: RE: ServerPageAction:
XMLFragment reuse in XSL transformer
There's probably about half a dozen ways to do this. Perhaps
one of the simplest is just to create your own caching generator and use
aggregation (with any other XML you may need)in the
pipeline.
In
the generator you'll need to implement the setup method to see the
objectModel, something like the following:
private gunk mySessionData = null;
public void setup( SourceResolver resolver, Map objectModel, String
src, Parameters parms ) throws
ProcessingException, SAXException,
IOException {
if (mySessionData == null )
{
super.setup(
resolver, objectModel, src, parms );
Request
request =
(Request)ObjectModelHelper.getRequest(objectModel);
Session session =
request.getSession(false);
if (session != null) {
//
save a pointer to your session data for use in the generate
method
mySessionData =
}
} }
Now in your generate method just pick up whatever data hangs off of
"mySessionData" and away you go
-Original Message-From:
Christian Kurz [mailto:[EMAIL PROTECTED]]Sent: Thursday, October 17,
2002 11:26 AMTo: [EMAIL PROTECTED]Subject:
ServerPageAction: XMLFragment reuse in XSL transformerHello cocoon-users,
I need to generate some tiny XML elements
(XMLFragment) within a ServerPageAction and I would like to use this
XMLFragment later on in an XSL transformer, that is fed by an xml
generator. The XMLFragment captured in the
ServerPageAction is basically saying, which nodes are to be returned from
the big input document.
From some other message in this group I have
understood, that passing objects is only possible through session or
request objects, but not through sitemap variables. I don't like to use a
request generator as the starting point of the pipeline, as I'd loose
cacheability at a very early step in the pipeline.With a quite
bigxml input document,this does not seem a good idea to
me.
So I am currently struggling how to get a
piece of XML, that isattached to a session or request object, into
the xsl transformer. Has anybody tried this before e.g. using an XSL
extension?
Any help or hints appreciated!
Thank you in advance,
Christian
