如何从Shell执行XPath单行？ [英] How to execute XPath one-liners from shell?

问题描述

是否有针对Ubuntu和/或CentOS的软件包，该软件包具有可以执行XPath单一代码的命令行工具，如 foo // element @ attribute filename.xml 或 foo // element @ attribute< filename.xml 并逐行返回结果？

我正在寻找可以让我 apt-get install foo 或 yum install foo ，即可直接使用，无需包装或其他修改。 / p>

以下是一些接近的例子：

Nokogiri。如果我编写此包装器，则可以按上述方式调用包装器：

 ＃！/ usr / bin / ruby​​ 
 
需要'nokogiri'
 
 Nokogiri :: XML（STDIN）.xpath（ARGV [0]）。each | row | 
放置行
结束
  

XML :: XPath。可以与此包装一起使用：

 ＃！/ usr / bin / perl 
 
 use strict; 
使用警告； 
使用XML :: XPath; 
 
 my $ root = XML :: XPath-> new（ioref =>'STDIN'）;我的$ node的
（$ root-> find（$ ARGV [0]）-> get_nodelist）{
 print（$ node-> getData， \n）; 
} 
  

xpath :: XPath返回太多噪音，-NODE-和 attribute = value 。

来自XML :: Twig的

xml_grep 无法处理不返回元素的表达式，因此不能用于未经进一步处理而提取属性值。

编辑：

echo cat // element / @ attribute | xmllint --shell filename.xml 返回类似于 xpath 的噪声。

xmllint --xpath // element / @ attribute filename.xml 返回 attribute = value 。

xmllint --xpath'string（// element / @ attribute）'filename.xml 返回我想要的内容，但仅针对第一个

对于另一个几乎可以解决该问题的解决方案，这是一个XSLT，可用于评估任意XPath表达式（需要在XSLT处理器中使用dyn：evaluate支持）：

 <？xml version = 1.0？> 
< xsl：stylesheet xmlns：xsl = http://www.w3.org/1999/XSL/Transform version = 1.0 
 xmlns：dyn = http：// exslt。 org / dynamic extension-element-prefixes = dyn> 
< xsl：output omit-xml-declaration = yes indent = no method = text /> 
< xsl：template match = /> 
< xsl：for-each select = dyn：evaluate（$ pattern）> 
< xsl：value-of select = dyn：evaluate（$ value） /> 
< xsl：value-of select =’&＃10;’ /> 
< / xsl：for-each> 
< / xsl：template> 
< / xsl：stylesheet> 
  

运行 xsltproc --stringparam pattern // element / @ attribute- stringparam值。任意-xpath.xslt filename.xml 。

解决方案

您应该尝试以下工具：

• xmlstarlet ：可以编辑，选择，转换...默认未安装，xpath1


• xmllint ：通常默认情况下与 libxml2-utils ，xpath1一起安装（检查我的包装，使-xpath 可以在非常老的发行版上启用和换行符分隔输出（v <2.9.9）


• xpath ：通过perl的模块 XML安装： ：XPath ，xpath1


• xml_grep ：通过perl的模块 XML ::安装嫩枝，xpath1（有限的xpath使用）


• xidel ：xpath3


• saxon-lint ：我自己的项目，@Michael Kay的Saxon-HE Java库的包装，xpath3

xmllint 随附 libxml2-utils （可以用作interacti带有-shell 开关的ve shell）

xmlstarlet 是 xmlstarlet 。

xpath 随附perl的模块 XML :: Xpath

xml_grep 随perl的模块 一起提供XML :: Twig

xidel 是 xidel

saxon-lint 使用 SaxonHE 9.6 ， XPath 3.x （+复古兼容性）

Ex：

  xmllint --xpath'// element / @ attribute 'file.xml 
 xmlstarlet sel -t -v // element / @ attribute; file.xml 
 xpath -q -e'// element / @ attribute'file.xml 
 xidel -se'// element / @ attribute'file.xml 
 saxon-lint- xpath'// element / @ attribute'file.xml 
  

• xmlstarlet页面


• man xmllint


• xpath页面


• xml_grep


• xidel


• saxon-lint

。

Is there a package out there, for Ubuntu and/or CentOS, that has a command-line tool that can execute an XPath one-liner like foo //element@attribute filename.xml or foo //element@attribute < filename.xml and return the results line by line?

I'm looking for something that would allow me to just apt-get install foo or yum install foo and then just works out-of-the-box, no wrappers or other adaptation necessary.

Here are some examples of things that come close:

Nokogiri. If I write this wrapper I could call the wrapper in the way described above:

#!/usr/bin/ruby

require 'nokogiri'

Nokogiri::XML(STDIN).xpath(ARGV[0]).each do |row|
  puts row
end

XML::XPath. Would work with this wrapper:

#!/usr/bin/perl

use strict;
use warnings;
use XML::XPath;

my $root = XML::XPath->new(ioref => 'STDIN');
for my $node ($root->find($ARGV[0])->get_nodelist) {
  print($node->getData, "\n");
}

xpath from XML::XPath returns too much noise, -- NODE -- and attribute = "value".

xml_grep from XML::Twig cannot handle expressions that do not return elements, so cannot be used to extract attribute values without further processing.

EDIT:

echo cat //element/@attribute | xmllint --shell filename.xml returns noise similar to xpath.

xmllint --xpath //element/@attribute filename.xml returns attribute = "value".

xmllint --xpath 'string(//element/@attribute)' filename.xml returns what I want, but only for the first match.

For another solution almost satisfying the question, here is an XSLT that can be used to evaluate arbitrary XPath expressions (requires dyn:evaluate support in the XSLT processor):

<?xml version="1.0"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"
    xmlns:dyn="http://exslt.org/dynamic" extension-element-prefixes="dyn">
  <xsl:output omit-xml-declaration="yes" indent="no" method="text"/>
  <xsl:template match="/">
    <xsl:for-each select="dyn:evaluate($pattern)">
      <xsl:value-of select="dyn:evaluate($value)"/>
      <xsl:value-of select="'&#10;'"/>
    </xsl:for-each> 
  </xsl:template>
</xsl:stylesheet>

Run with xsltproc --stringparam pattern //element/@attribute --stringparam value . arbitrary-xpath.xslt filename.xml.

解决方案

You should try these tools :

• xmlstarlet : can edit, select, transform... Not installed by default, xpath1
• xmllint : often installed by default with libxml2-utils, xpath1 (check my wrapper to have --xpath switch on very old releases and newlines delimited output (v < 2.9.9)
• xpath : installed via perl's module XML::XPath, xpath1
• xml_grep : installed via perl's module XML::Twig, xpath1 (limited xpath usage)
• xidel: xpath3
• saxon-lint : my own project, wrapper over @Michael Kay's Saxon-HE Java library, xpath3

xmllint comes with libxml2-utils (can be used as interactive shell with the --shell switch)

xmlstarlet is xmlstarlet.

xpath comes with perl's module XML::Xpath

xml_grep comes with perl's module XML::Twig

xidel is xidel

saxon-lint using SaxonHE 9.6 ,XPath 3.x (+retro compatibility)

Ex :

xmllint --xpath '//element/@attribute' file.xml
xmlstarlet sel -t -v "//element/@attribute" file.xml
xpath -q -e '//element/@attribute' file.xml
xidel -se '//element/@attribute' file.xml
saxon-lint --xpath '//element/@attribute' file.xml

• xmlstarlet page
• man xmllint
• xpath page
• xml_grep
• xidel
• saxon-lint

.

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