XMLStarlet：每个项目打印一行，同时使用来自父元素的数据

Question

我有 XML 数据以这种方式格式化：

<XML>
    <Waveforms Time="01/01/2009 3:00:02 AM">
        <WaveformData Channel="I">1, 2, 3, 4, 5, 6 </WaveformData>
        <WaveformData Channel="II">9, 8, 7, 6, 5, 4 </WaveformData>
    </Waveforms>
    <Waveforms Time="01/01/2009 3:00:04 AM">
        <WaveformData Channel="I">1, 2, 3, 4, 5, 6 </WaveformData>
        <WaveformData Channel="II">9, 8, 7, 6, 5, 4 </WaveformData>
    </Waveforms>
</XML>

我正在尝试使用 xmlstarlet 将此数据解析为文本文件（以逗号分隔）。所需的输出如下所示：

Time Attribute, Channel Attribute, Data
01/01/2009 3:00:02 AM, I, 1, 2, 3, 4, 5, 6
01/01/2009 3:00:02 AM, II, 9, 8, 7, 6, 5, 4
01/01/2009 3:00:02 AM, I, 1, 2, 3, 4, 5, 6
01/01/2009 3:00:02 AM, II, 9, 8, 7, 6, 5, 4

我能想到的最好的是：

 xmlstarlet sel -T -t -m //XML/Waveforms -v @Time -o "," -m Waves -v WaveformData/@Channel -o "," -v WaveformData -o "," -b -n testwave2.xml > testwave.txt

结果如下：

 01/01/2009 3:00:02 AM, I, 1, 2, 3, 4, 5, 6, II, 9, 8, 7, 6, 5, 4
 01/01/2009 3:00:04 AM, I, 1, 2, 3, 4, 5, 6, II, 9, 8, 7, 6, 5, 4

很清楚如何为每个 Waveforms 打印一行，但不清楚如何为每个 WaveformData 打印一行如果我想包含其父项的时间属性。这可以做到吗？或者，我是否应该变通并进行一些切片和粘贴以在之后将其修复到后端？

Answer 1

搜索 WaveformData——因为它是你想要的，每行一行——然后在树中向上遍历以找到你的时间元素。

$ xmlstarlet sel -T -t -m /XML/Waveforms/WaveformData \
     -v ../@Time -o "," \
     -v @Channel -o "," \
     -v . -n <in.xml
01/01/2009 3:00:02 AM,I,1, 2, 3, 4, 5, 6 
01/01/2009 3:00:02 AM,II,9, 8, 7, 6, 5, 4 
01/01/2009 3:00:04 AM,I,1, 2, 3, 4, 5, 6 
01/01/2009 3:00:04 AM,II,9, 8, 7, 6, 5, 4

或者，如果您知道每个 Waveforms 将恰好有两个 WaveformData 子项，您可以执行以下操作：

$ xmlstarlet sel -T -t -m /XML/Waveforms \
    -v ./@Time -o ",I,"  -v './WaveformData[@Channel="I"]' -n \
    -v ./@Time -o ",II," -v './WaveformData[@Channel="II"]' -n <in.xml
01/01/2009 3:00:02 AM,I,1, 2, 3, 4, 5, 6
01/01/2009 3:00:02 AM,II,9, 8, 7, 6, 5, 4
01/01/2009 3:00:04 AM,I,1, 2, 3, 4, 5, 6
01/01/2009 3:00:04 AM,II,9, 8, 7, 6, 5, 4

Answer 2

为了对 Charles Duffy 的回答稍作修改，您可以使用 concat() 函数稍微简化它，并使用初始模板来提供 CSV header:

$ xmlstarlet sel \
    -t -o 'Time Attribute, Channel Attribute, Data' -n \
    -t -m '//Waveforms/WaveformData' \
       -v 'concat(../@Time, ", ", @Channel, ", ", text())' -n \
  waveforms.xml
Time Attribute, Channel Attribute, Data
01/01/2009 3:00:02 AM, I, 1, 2, 3, 4, 5, 6
01/01/2009 3:00:02 AM, II, 9, 8, 7, 6, 5, 4
01/01/2009 3:00:04 AM, I, 1, 2, 3, 4, 5, 6
01/01/2009 3:00:04 AM, II, 9, 8, 7, 6, 5, 4

XMLStarlet：每个项目打印一行，同时使用来自父元素的数据

XMLStarlet: Printing one line per item, while using datum from parent element

xml

bash

xpath

parsing

xmlstarlet