首页 > 解决方案 > 如何在 Linux shell 脚本中仅提取 xml 树响应中的顶级元素?

问题描述

下面是显示名称列表和 manager_add 的 shell 脚本

name=($(grep -oP '(?<=name>)[^<]+' <<< "$vsppProxy_res"))

for i in ${!name[*]}
do
  echo "$i" "${name[$i]}"
  done

managers=($(grep -oP '(?<=manager_addr>)[^<]+' <<< "$vsppProxy_res"))

for i in ${!managers[*]}
do
  echo "$i" "${managers[$i]}"
  done

到目前为止的输出是:

0 名称0 1 名称1 2 名称2 3 名称3 .................................... ……………………………………………………………………………………………………………………………………………………………… .... 0 manager_add0 1 manager_add1 2 manager_add2 ................................... ...........

xml 响应包含 3 个顶级元素,例如, <elem id="0">每个顶级元素都包含子元素,例如<elem id="0">,具体取决于大小。但是,要求只需要提取顶级元素<elem id="0">

示例 xml 如下所示:

<X>
<regs>
<elem id="0">
<id>1</id>
<name>name0</name>
<warn>1</warn>
<manager_addr>manager_addr0</manager_addr>
<warn_desc>
<size>14</size>
<elem id="0">
<sev>2</sev>
<description>description</description>
<warning_id>1</warning_id>
<deployment_id>1</deployment_id>
<context_id>00</context_id>
<num_of_occurrences>1</num_of_occurrences>
<deployment_name>prod1</deployment_name>
</elem>
<elem id="1">
<sev>2</sev>
<description>description</description>
<warning_id>1</warning_id>
<deployment_id>1</deployment_id>
<context_id>00</context_id>
<num_of_occurrences>1</num_of_occurrences>
<deployment_name>prod1</deployment_name>
</elem>
</warn_desc>
</elem>
<elem id="1">
<id>2</id>
<name>name1</name>
<warn>1</warn>
<manager_addr>manager_addr1</manager_addr>
<warn_desc>
<size>1</size>
<elem id="0">
<sev>3</sev>
<description>description</description>
<warning_id>2</warning_id>
<context_id>00</context_id>
<num_of_occurrences>1</num_of_occurrences>
</elem>
</warn_desc>
</elem>
</regs>
</X>

预期的输出应该是:

经理:name0 manager_add0 ................................................... ……………………………………………………………………………………………………

请提供您的建议。谢谢你。

标签: xmllinuxshell

解决方案


尝试使用正则表达式解析 XML 是个坏主意。您应该使用支持 XML 的工具。转换 XML 文档的一个明显选择是XSLT

考虑以下 shell 脚本,它将 XSLT 样式表应用于在命令行中传递给它的文件:

#!/bin/sh

# Use a temporary file for the XSLT stylesheet
stylesheet=$(mktemp)
cat >"$stylesheet" <<'EOF'
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
  <xsl:output method="text" encoding="UTF-8" />
  <xsl:variable name="newline"><xsl:text>
</xsl:text></xsl:variable>
  <xsl:template match="/X">
    <xsl:for-each select="regs/elem">
      <xsl:value-of
          select="concat('Manager: ', name, ' ', manager_addr, $newline)" />
    </xsl:for-each>
  </xsl:template>
</xsl:stylesheet>
EOF

# Adjust as needed for whichever xslt processor you want to use
xsltproc "$stylesheet" "$1"
# xalan -xsl "$stylesheet" -in "$1"
# xmlstarlet tr "$stylesheet" "$1"

rm -f "$stylesheet"

用法:

$ ./transform.sh input.xml
Manager: name0 manager_addr0
Manager: name1 manager_addr1

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