Cool. Nice example. Thanks.

From: David Cook <dcook@prosentient.com.au>
Sent: Monday, March 11, 2024 12:27 AM
To: Marcel de Rooy <M.de.Rooy@rijksmuseum.nl>; 'Koha Devel' <koha-devel@lists.koha-community.org>
Subject: RE: [Koha-devel] Random XSLT knowledge

Hi Marcel,

Sure!

Before Koha started using “http://exslt.org/strings” to encode URIs, I used to use register_function to add my own function to do that.

vi C4/XSLT.pm
Add a line near the top like:

XML::LibXSLT->register_function("http://wwww.prosentient.com.au/xsltperl", "uri-escape",\&Koha::Prosentient::Biblio::Urls::xslt_uri_escape);

Write a function like this:

sub xslt_uri_escape {

my ($uri) = @_;

#$uri should always be a XML::LibXML::Nodelist, even if that Nodelist just contains 1 URI

if (ref $uri eq "XML::LibXML::NodeList"){

$uri->foreach(

sub {

my ( $node ) = @_;

#If the node has child (text) nodes

if ($node->hasChildNodes()){

my @childNodes = $node->childNodes();

if (@childNodes){

foreach my $childNode (@childNodes){

if (my $textdata = $childNode->data){

#Trim whitespace

$textdata =~ s/^\s+|\s+$//g;

my $encoded_url = URI::Encode::uri_encode($textdata, { encode_reserved => 0 });

if ($encoded_url){

#Replace the existing URI data with the encoded URI data

$childNode->setData($encoded_url);

}

);

}

return $uri;

}

Add the namespace at the top of your XSLT:

xmlns:pro="http://wwww.prosentient.com.au/xsltperl"

Call the function on some XML:

<xsl:value-of select="pro:uri-escape(//marc:datafield[@tag=856]/marc:subfield[@code='u'])"/>

More recently, I’ve done more complicated things like looking up item urls for that biblio record, deduplicating them against the 856$u, and adding them to the online access in the search results. I continue to take into account OpacHiddenItems and its associated preferences. Since it’s operating at the Perl level, I’m able to check the C4::Context->userenv for the patron details as well.

David Cook

Senior Software Engineer

Prosentient Systems

Suite 7.03

6a Glen St

Milsons Point NSW 2061

Australia

Office: 02 9212 0899

Online: 02 8005 0595

From: Marcel de Rooy <M.de.Rooy@rijksmuseum.nl>
Sent: Friday, 8 March 2024 6:13 PM
To: 'Koha Devel' <koha-devel@lists.koha-community.org>; David Cook <dcook@prosentient.com.au>
Subject: Re: [Koha-devel] Random XSLT knowledge

Hi David,

Thanks for sharing.

Would you have an example of how you use register_function with Koha functions to share?

Marcel

Van: Koha-devel <koha-devel-bounces@lists.koha-community.org> namens David Cook via Koha-devel <koha-devel@lists.koha-community.org>
Verzonden: vrijdag 8 maart 2024 03:02
Aan: 'Koha Devel' <koha-devel@lists.koha-community.org>
Onderwerp: [Koha-devel] Random XSLT knowledge

Hi all,

I’ve been working on performance issues, and in the process I got looking at XSLTs.

I just wanted to share that it’s possible to pass strings to the XSLT’s transform() method:

- return $engine->transform($xmlrecord, $xslfilename ); #file or URL

+ return $engine->transform({

+ xml => $xmlrecord,

+ file => $xslfilename,

+ parameters => {

+ test => "'$test_str'",

+ },

+ }); #file or URL

It’s somewhat limited in that you can only pass strings and I think there’s a small limit on the number of parameters you can pass (not sure if it’s 32 or 255), but I thought it was interesting. It would allow you to pass some data that you have at hand on a per-XML record basis without having to mangle the XML record (like we do with items and system preferences).

In the end, I didn’t end up using it though. Instead, I use XML::LibXSLT->register_function() to provide access to Koha functions from the XSLT, and in this case that meets my needs.

Anyway, back to it..