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python-3.x - Python - 如何解析这个嵌套的 xml 文件？

问题描述

我正在尝试将此嵌套的 xml 文件解析为数据框。这是xml的示例：

    <?xml version='1.0' encoding='UTF-8'?>
<response xmlns="http://www...">
  <sensor-time timezone="America/New_York">2020-08-10T12:19:26-04:00</sensor-time>
  <status>
    <code>OK</code>
  </status>
  <content>
    <elements>
      <element>
        <element-id>0</element-id>
        <element-name>Line 0</element-name>
        <sensor-type>SINGLE_SENSOR</sensor-type>
        <data-type>LINE</data-type>
        <from>2020-08-10T10:00:00-04:00</from>
        <to>2020-08-10T12:00:00-04:00</to>
        <resolution>FIVE_MINUTES</resolution>
        <measurements>
          <measurement>
            <from>2020-08-10T10:00:00-04:00</from>
            <to>2020-08-10T10:05:00-04:00</to>
            <values>
              <value label="fw">0</value>
              <value label="bw">0</value>
            </values>
          </measurement>
          <measurement>
            <from>2020-08-10T10:05:00-04:00</from>
            <to>2020-08-10T10:10:00-04:00</to>
            <values>
              <value label="fw">0</value>
              <value label="bw">0</value>
            </values>
          </measurement>
          <measurement>
            <from>2020-08-10T10:10:00-04:00</from>
            <to>2020-08-10T10:15:00-04:00</to>
            <values>
              <value label="fw">0</value>
              <value label="bw">0</value>
            </values>
          </measurement>
          <measurement>
      </element>
      <element>
        <element-id>1</element-id>
        <element-name>GP Test CL.01</element-name>
        <sensor-type>SINGLE_SENSOR</sensor-type>
        <data-type>LINE</data-type>
        <from>2020-08-10T10:00:00-04:00</from>
        <to>2020-08-10T12:00:00-04:00</to>
        <resolution>FIVE_MINUTES</resolution>
        <measurements>
          <measurement>
            <from>2020-08-10T10:00:00-04:00</from>
            <to>2020-08-10T10:05:00-04:00</to>
            <values>
              <value label="fw">0</value>
              <value label="bw">0</value>
            </values>
          </measurement>
          <measurement>
            <from>2020-08-10T10:05:00-04:00</from>
            <to>2020-08-10T10:10:00-04:00</to>
            <values>
              <value label="fw">0</value>
              <value label="bw">0</value>
            </values>
          </measurement>
          <measurement>
            <from>2020-08-10T10:10:00-04:00</from>
            <to>2020-08-10T10:15:00-04:00</to>
            <values>
              <value label="fw">0</value>
              <value label="bw">0</value>
            </values>
          </measurement>
          <measurement>
      </element>
    </elements>
  </content>
  <sensor-info>
    <serial-number>D1:82:34:5Z:3Q:3D</serial-number>
    <ip-address>000.000.00.0</ip-address>
    <name>Demo</name>
    <group>Test Devices</group>
    <device-type>PC2</device-type>
  </sensor-info>
</response>

我尝试使用 xmltodict 库，并且可以提取单个元素，但是由于它是嵌套的并且在 xml 中具有多个元素和测量值，因此当我尝试循环遍历它时，我无法使其正常工作。这是我到目前为止的代码：

import pandas as pd
import glob
import xmltodict
# Look for all xml files in directory
result = []
for file in glob.glob('*.xml'):
    with open(file) as fd:
        # Load each xml file and append it
        doc = xmltodict.parse(fd.read())
        for element in doc['response']['content']['elements']['element']:
            for m in element['measurements']:
                data = {}
                for val in m['value']:
                    data['SERIAL_NUMBER'] = doc['response']['sensor-info']['serial-number']
                    data['IP'] = doc['response']['sensor-info']['ip-address']
                    data['name'] = doc['response']['sensor-info']['name']
                    data['Group'] = doc['response']['sensor-info']['group']
                    data['Device Type'] = doc['response']['sensor-info']['device-type']
                    data['element-id'] = element['element-id']
                    data['Line name'] = element['element-name']
                    data['From time'] = m['from']
                    data['to time'] = m['to']
                    data[val['label']] = val['value']
                result.append(data)
                df = pd.DataFrame(result)

我得到的错误是：“TypeError：字符串索引必须是整数”在元素中查找 m 的开头。

最终我想要得到的是这种格式的输出：

在此处输入图像描述

知道如何让它工作吗？

标签： python-3.xxml-parsingxmltodict

解决方案

为了让你至少接近我认为你想要去的地方，我会按照这些思路做一些事情（显然，你可以根据需要修改它）：

rows = []
for element in doc.xpath('//elements//element'):
    row = []
    row.extend([(doc.xpath('//sensor-info/ip-address/text()')[0]),
    (doc.xpath('//sensor-info/name/text()')[0]),
    (doc.xpath('//sensor-info/device-type/text()')[0]),
    (doc.xpath('//sensor-info/group/text()')[0]),
    (element.xpath('.//element-id/text()')[0]),
    (element.xpath('.//element-name/text()')[0]),
    (measurement.xpath('//to/text()')[0]),
    (measurement.xpath('//from/text()')[0]),
    (measurement.xpath('//values[1]/value[@label="fw"]/text()')[0]),
    (measurement.xpath('//values[1]/value[@label="bw"]/text()')[0])])
    rows.append(row)
pd.DataFrame(rows, columns = cols)

输出（基于问题中的示例 xml）：

ip  sensor name     device  group   elem id     elem name   to  from    fw  bw
0   000.000.00.0    Demo    PC2     Test Devices    0   Line 0  2020-08-10T12:00:00-04:00   2020-08-10T10:00:00-04:00   0   0
1   000.000.00.0    Demo    PC2     Test Devices    1   GP Test CL.01   2020-08-10T12:00:00-04:00   2020-08-10T10:00:00-04:00   0   0

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