在perl中,我如何循环这个结构？

Question

我正在创建一个xml来传递给API,API返回它(数据转储):

    (
    "Data::Dump",
    {
      SiteDevices => {
        "device"  => {
                       1102   => { address => "1.2.3.4", riskfactor => "1.0", riskscore => "0.0" },
                       1136   => { address => "1.2.3.5", riskfactor => "1.0", riskscore => "0.0" },
                       20491  => { address => "1.2.3.6", riskfactor => "1.0", riskscore => "0.0" },
                       129644 => { address => "1.2.3.7", riskfactor => "1.0", riskscore => "0.0" },
                       129645 => { address => "1.2.3.8", riskfactor => "1.0", riskscore => "0.0" },
                       130408 => { address => "1.2.3.9", riskfactor => "1.0", riskscore => "0.0" },
                       135975 => { address => "1.2.3.10", riskfactor => "1.0", riskscore => "0.0" },
                       137642 => { address => "1.2.3.11", riskfactor => "1.0", riskscore => "0.0" },
                     },
        "site-id" => 27,
      },
      success => 1,
    },
)

我想循环并打印与它们相关的设备和IP,而我在生活中无法想出任何代码来完成它.我错过了什么？!我试图循环哈希,散列哈希等等.永远不能让它工作.如果你们中的任何人有一秒钟并且可以提供答案,那么我可以羞愧地摇头,那真是棒极了.

我试过了:

foreach my $key (keys %{ $output->{‘SiteDevices’}->{‘device’} }) {
         print $key 
         print $key->{‘address’} 
}

和

foreach my $key (keys %{ $output{‘SiteDevices’}{‘device’} }) {
         print $key 
         print $key{‘address’} 
}

但都不起作用.

Answer 1

你提到这是解析的XML.它看起来像你与解析它XML::Simple和这只是不是一个好主意.

为什么不呢:

#!/usr/bin/env perl
use strict;
use warnings;

use XML::Twig; 

## get xml somehow here. parsefile if it's a file already. 
my $twig = XML::Twig -> new -> parse ( $your_xml );

foreach my $device ( $twig -> get_xpath('//devices' ) ) {
   print $device -> att('name'), " => "; 
   print $device -> att('address'),"\n";
}

这里有用的是xpath- 它不是正则表达式,但它有点类似 - 它适用于XML.在这种情况下,//device说' <device>在树中的任何地方找到一个节点.(然后我们提取属性).

这可能适用于您的方案,但您可以通过指定更长的路径来更具体:

• ./device - 直接位于当前节点下方.
• .//device - 当前节点下方的任何位置.
• /root/SiteDevices/device - 特定匹配此"树"的节点.

您还可以使用xpath搜索属性:

• .//device[@name="1136"] 会找到具有适当价值和属性的东西.

有关如何执行此操作的一些指南,请参阅XML Twig快速参考.