# $Id: Utils.pm,v 1.5 2006-11-01 11:46:10 mike Exp $ package ZOOM::IRSpy::Utils; use 5.008; use strict; use warnings; use Exporter 'import'; our @EXPORT_OK = qw(xml_encode irspy_xpath_context modify_xml_document inheritance_tree); use XML::LibXML; use XML::LibXML::XPathContext; our $IRSPY_NS = 'http://indexdata.com/irspy/1.0'; # Utility functions follow, exported for use of web UI # I can't -- just can't, can't, can't -- believe that this function # isn't provided by one of the core XML modules. But the evidence all # says that it's not: among other things, XML::Generator and # Template::Plugin both roll their own. So I will do likewise. D'oh! # sub xml_encode { my ($text) = @_; $text =~ s/&/&/g; $text =~ s//>/g; $text =~ s/['']/'/g; $text =~ s/[""]/"/g; return $text; } sub irspy_xpath_context { my($zoom_record) = @_; my $xml = $zoom_record->render(); my $parser = new XML::LibXML(); my $doc = $parser->parse_string($xml); my $root = $doc->getDocumentElement(); my $xc = XML::LibXML::XPathContext->new($root); $xc->registerNs(e => 'http://explain.z3950.org/dtd/2.0/'); $xc->registerNs(i => $IRSPY_NS); return $xc; } sub modify_xml_document { my($xc, $fieldsByKey, $data) = @_; my $nchanges = 0; foreach my $key (keys %$data) { my $value = $data->{$key}; my $ref = $fieldsByKey->{$key} or die "no field '$key'"; my($name, $nlines, $caption, $xpath, @addAfter) = @$ref; #print "Considering $key='$value' ($xpath)
\n"; my @nodes = $xc->findnodes($xpath); if (@nodes) { warn scalar(@nodes), " nodes match '$xpath'" if @nodes > 1; my $node = $nodes[0]; if ($node->isa("XML::LibXML::Attr")) { if ($value ne $node->getValue()) { $node->setValue($value); $nchanges++; print "Attr $key: '", $node->getValue(), "' -> '$value' ($xpath)
\n"; } } elsif ($node->isa("XML::LibXML::Element")) { # The contents could be any mixture of text and # comments and maybe even other crud such as processing # instructions. The simplest thing is just to throw it all # away and start again, making a single Text node the # canonical representation. But before we do that, # we'll check whether the element is already # canonical, to determine whether our change is a # no-op. my $old = "???"; my @children = $node->childNodes(); if (@children == 1) { my $child = $node->firstChild(); if (ref $child && ref $child eq "XML::LibXML::Text") { $old = $child->getData(); next if $value eq $old; } } $node->removeChildNodes(); my $child = new XML::LibXML::Text($value); $node->appendChild($child); $nchanges++; print "Elem $key: '$old' -> '$value' ($xpath)
\n"; } else { warn "unexpected node type $node"; } } else { next if !$value; # No need to create a new empty node my($ppath, $element) = $xpath =~ /(.*)\/(.*)/; dom_add_element($xc, $ppath, $element, $value, @addAfter); print "Add $key ($xpath) = '$value'
\n"; $nchanges++; } } return $nchanges; } sub dom_add_element { my($xc, $ppath, $element, $value, @addAfter) = @_; print "Adding '$value' at '$ppath' after (", join(", ", map { "'$_'" } @addAfter), ")
\n"; my @nodes = $xc->findnodes($ppath); if (@nodes == 0) { # Oh dear, the parent node doesn't exist. We could make it, # but for now let's not and say we did. warn "no parent node '$ppath': not adding '$element'='$value'"; return; } warn scalar(@nodes), " nodes match parent '$ppath'" if @nodes > 1; my $node = $nodes[0]; if (1) { my $text = xml_encode(inheritance_tree($xc)); $text =~ s/\n/$1/sg; print "
$text
\n"; } } sub inheritance_tree { my($type, $level) = @_; $level = 0 if !defined $level; return "Woah! Too deep, man!\n" if $level > 20; $type = ref $type if ref $type; my $text = ""; $text = "--> " if $level == 0; $text .= ("\t" x $level) . "$type\n"; my @ISA = eval "\@${type}::ISA"; foreach my $superclass (@ISA) { $text .= inheritance_tree($superclass, $level+1); } return $text; } #print "Loaded ZOOM::IRSpy::Utils.pm"; 1;