Question

我正在比较两个XML文件。如果我发现其中一个文件中缺少某个节点，我想将其插入另一个文件中。以下是我一直在尝试的方法：

my $out_file = 'fbCI_report.xml';
open my $fh_out, '>>', $out_file or die "Can't open $out_file for writing: $!";

my $currentReport = XML::Twig->new( pretty_print => 'indented' );
$currentReport->parsefile($path_to_currentReport);
print "Loaded current report.\n";

my $newReport = XML::Twig->new( pretty_print => 'indented' );
$newReport->parsefile($path_to_newReport);
print "Loaded new report.\n";

my $currentRoot   = $currentReport->root;             # get the root
my $currentBuilds = $currentRoot->first_child();      # get the builds node
my $currentXCR    = $currentBuilds->first_child();    # get the xcr node

my $newRoot   = $newReport->root;                     # get the root
my $newBuilds = $newRoot->first_child();              # get the builds node
my $newXCR    = $newBuilds->first_child();            # get the xcr node

my @currentXCRarray = $currentBuilds->children('xcr');
my @newXCRarray     = $newBuilds->children('xcr');
my $numberOfxcr     = $newBuilds->children_count();

foreach my $currentXCRmod ( @currentXCRarray ) {

    my $currentID = $currentXCRmod->att("id");

    foreach my $newXCRmod (@newXCRarray) {

        my $newID = $newXCRmod->att("id");

        if ( $newID == $currentID ) {
            last;
        }
        elsif ( $count == $numberOfxcr && $newID != $currentID ) {
            my $insert = $currentBuilds->insert_new_elt($newXCRmod);
            print "XCR does not exist in current report, adding it..\n";
        }

        $count++;
    }
}

print $fh_out $currentReport->sprint();
close $fh_out;

但是，这不会插入具有相应子节点的节点，但我猜是对节点的引用：<XML::Twig::Elt=HASH(0x326efe0)/>。有没有办法正确插入节点？我还没有在CPAN网站上找到任何东西。

示例数据，current.xml：

<project>
  <builds>
    <xcr id="13367" buildable="false">
        <artifact name="rb"/>
        <artifact name="syca"/>
    </xcr>
    <xcr id="13826" buildable="false">
        <artifact name="dcs"/>
    </xcr>
  <\builds>
<\project>

new.xml：

<project>
<builds>
    <xcr id="13367" buildable="false">
        <artifact name="rb"/>
        <artifact name="syca"/>
    </xcr>
    <xcr id="13826" buildable="false">
        <artifact name="dcs"/>
    </xcr>
    <xcr id="10867" buildable="true">
        <artifact name="smth"/>
        <artifact name="top"/>
        <artifact name="tree"/>
    </xcr>
<\builds>
<\project>

Answer 1

您应该移动节点（我不记得当您尝试插入已经属于树的元素时会发生什么）。所以写$newXCRmo->move( first_child( $currentBuilds))，看看这是否会改善这种情况。

我没有太多时间查看您的代码，因此可能存在其他问题。

Answer 2

你是对的 - 这是XML::Twig::Elt的字符串化文本。

问题是 - insert_new_elt 创建新元素。所以你正在做的就是有效地“打印”元素id（XML::Twig::Elt=HASH(0x326efe0)）并创建一个名为that的新节点。

但你不想这样做 - 你想要复制一个现有的。

所以我建议你想做的是：

my $copied_elt = $currentXCRmod -> copy;
$copied_elt -> paste ( last_child => $currentBuilds );

将传递元素（进入'last_child'位置）。

虽然我建议你的循环也许你也可以改进 - 我建议你看一下twig_handler，检查解析文件中存在哪个ID：

my %seen_id; 
sub collect_ids {
   my ( $twig, $element ) = @_;
   $seen_id { $element->att('id') } ++; 
}

然后在解析时调用它：

my $currentReport = XML::Twig->new(twig_handlers => { 'xcr' => \&collect_ids}, 
                                   pretty_print=>'indented');
$currentReport->parsefile($path_to_currentReport);

这将让您轻松比较/复制哪些存在或不存在。

或者（基于您目前的XML样本）：

#!/usr/bin/env perl

use strict;
use warnings 'all';

use Data::Dumper;
use XML::Twig;

my $current = XML::Twig -> new ( ) -> parsefile ('test1.xml');
my $new = XML::Twig -> new (  ) -> parsefile ( 'test2.xml'); 

my $cur_builds = $current -> root -> get_xpath('./builds',0);

foreach my $xcr ( $new -> findnodes('//xcr') ) {
   my $id = $xcr -> att('id'); 
   if ( not $current -> findnodes("//xcr[\@id=\"$id\"]") ) {
      print "$id not in current, copying\n"; 
      my $copy = $xcr -> copy; 
      $copy -> paste ( last_child => $cur_builds ); 
   }
}

$current -> set_pretty_print('indented_a');
$current -> print;

Answer 3

你有比较循环＆＃34;在里面＆＃34;

此外，测试$count == $numberOfxcr永远不会成功，因为循环foreach my $newXCRmod (@newXCRarray)将在真实之前终止

这是代码的改进版本，它使用XPath表达式以及any中的List::Util来使循环更简洁

use strict;
use warnings 'all';

use XML::Twig;
use List::Util 'any';

my ( $path_to_curr_report, $path_to_new_report ) = qw/ current.xml  new.xml /;
my $out_file = 'fbCI_report.xml';


my $curr_report = XML::Twig->new->parsefile($path_to_curr_report);
my $new_report  = XML::Twig->new->parsefile($path_to_new_report);

my ($curr_builds) = $curr_report->findnodes('/project/builds');

for my $new_xcr_mod ( $new_report->findnodes('/project/builds/xcr') ) {

    my $new_id = $new_xcr_mod->att('id');

    next if any { $new_id eq $_->att('id') } $curr_report->findnodes('/project/builds/xcr');

    print qq{XCR with ID "$new_id" does not exist in current report. Adding it.\n};
    $new_xcr_mod->copy->paste( last_child => $curr_builds );
}

{
    $curr_report->set_pretty_print('indented');
    open my $fh, '>', $out_file or die "Can't open $out_file for writing: $!";
    $curr_report->print($fh);
    close $fh;
}

输出

XCR with ID "10867" does not exist in current report. Adding it.

<project>
  <builds>
    <xcr buildable="false" id="13367">
      <artifact name="rb"/>
      <artifact name="syca"/>
    </xcr>
    <xcr buildable="false" id="13826">
      <artifact name="dcs"/>
    </xcr>
    <xcr buildable="true" id="10867">
      <artifact name="smth"/>
      <artifact name="top"/>
      <artifact name="tree"/>
    </xcr>
  </builds>
</project>

Perl：使用XML :: Twig插入XML :: Twig节点

3 个答案:

输出