Python 3x : 使用 python xml.etree 解析带有命名空间的 xml 文件

Question

我正在尝试使用 xml.etree 解析大型 xml 文件。它具有以下结构。

我对提取带有标题和出版商的参考文献特别感兴趣，如下图所示。

以下是我试过的代码示例。它不打印任何东西。感谢任何帮助。

import xml.etree.ElementTree as et

data = """<exist:result xmlns:exist="http://exist.sourceforge.net/NS/exist" exist:hits="1" exist:start="1" exist:count="1" exist:compilation-time="0" exist:execution-time="0">
    <events>
        <paging page="9" pageNumberOfRecords="20" totalNumberOfRecords="215"/>
        <WeatherEvent xmlns="http://hwe.niwa.co.nz/schema/2011" xmlns:gml="http://www.opengis.net/gml" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://hwe.niwa.co.nz/schema/2011 ../hwe.xsd">
    <Identifier>November_2019_Timaru_Hail</Identifier>
    <Title> November 2019 Timaru Hail</Title>
    <StartDate>2019-11-20</StartDate> 
        <Abstract>A severe hailstorm over Timaru, with golf ball-sized hail stones, caused extensive damage to buildings and vehicles.</Abstract>
        <Notes/>
        <Regions>
            <Region name="Canterbury">
                <Hazards>
                    <Hazard type="Hail">
                        <Location name="Timaru">
                            <gml:Point gml:id="Timaru_1" srsName="urn:ogc:def:crs:EPSG:6.6:4326" srsDimension="2">
                                <gml:pos>-44.398445 171.255200</gml:pos>
                            </gml:Point>
                        </Location>
                        <Impacts>
                            <Impact type="InsuranceClaim" unit="$" value="130700000">Insurance claims totalled 0.7 million.</Impact>
                            
                            <Impact type="GeneralComment">Large hail stones smashed windows, pelted holes in roofs, damaged vehicles and forced the closure of businesses.</Impact>
                            <Impact type="GeneralComment">The Fire and Emergency NZ Mid-South Canterbury area commander said they had received 30 call-outs between noon and 2.40pm. Twenty one  of them were for hail or rain damage.</Impact>
                            <Impact type="GeneralComment">The South Canterbury Chamber of Commerce said there had been considerable damage and flooding with a number of businesses forced to close until their premises were secure and safe to open.  The Timaru library and the Aigantighe Art Gallery were both closed due to damage sustained.</Impact>
                            <Impact type="GeneralComment">A Timaru panel beating business estimated there were at least 10,000 vehicles in Timaru that were damaged by the hail.  Vehicles had dents, broken windscreens and broken wing mirrors.  The structural integrity of many of the damaged vehicles was found to be compromised.</Impact>
                            <Impact type="GeneralComment">An Australian-based team of hail damage repairers set up a base in Timaru to fix cars damaged in the hailstorm.  They anticipated that repairing hail-damaged cars in Timaru would take at least six months.</Impact>
                        </Impacts>
                    </Hazard>
                    <Hazard type="Hail">
                        <Location name="St Andrews">
                            <gml:Point gml:id="St_Andrews_1" srsName="urn:ogc:def:crs:EPSG:6.6:4326" srsDimension="2">
                                <gml:pos>-44.5301 171.1909</gml:pos>
                            </gml:Point>
                        </Location>
                        <Impacts>
                            <Impact type="GeneralComment">Federated Farmers reported there had been significant crop damage near St Andrews.</Impact>
                        </Impacts>
                    </Hazard>
                </Hazards>
            </Region>
        </Regions>
        <References>
            <Reference>
                <Title>Insurance Council of New Zealand (https://www.icnz.org.nz/natural-disasters/cost-of-natural-disasters/)</Title>
                <Type>Reference</Type>
            </Reference>            
            <Reference>
                <Title>Headline:  Giant hail stones hammer Timaru as storm moves up the country.</Title>
                <Type>Reference</Type>
                <Publisher>www.stuff.co.nz, 20 November 2019.  </Publisher>
            </Reference>
            <Reference>
                <Title>Headline:  Insurance companies face deluge of hail damage claims.</Title>
                <Type>Reference</Type>
                <Publisher>www.stuff.co.nz, 21 November 2019.  </Publisher>
            </Reference>
            <Reference>
                <Title>Headline:  Cars damaged in severe Timaru hailstorm failing warrents of fitness.</Title>
                <Type>Reference</Type>
                <Publisher>www.stuff.co.nz, 4 December 2019.  </Publisher>
            </Reference>
            <Reference>
                <Title>Headline:  Record insurance repairs for cars smashed by hail in Timaru.</Title>
                <Type>Reference</Type>
                <Publisher>www.stuff.co.nz, 23 December 2019.  </Publisher>
            </Reference>
            
        </References>
</WeatherEvent>
</events>
</exist:result>
"""

root = et.fromstring(data)

ns = {'exist':'http://exist.sourceforge.net/NS/exist', 'niwa':'http://hwe.niwa.co.nz/schema/2011'}


results = root.findall('exist:result', ns)
for event in results:
    weatherEvnt = event.find('niwa: events', ns)
    for WE in weatherEvnt:
        Ref = WE.find('niwa: WeatherEvent', ns)
        for x in Ref.find('niwa: References', ns):
            print(x.text)

Answer 1

问题至少包括：

根已经是exist:result，所以初始
```
results = root.findall('exist:result', ns)
```
returns 一个空列表，因为 exist:result 没有这样的 children.
名称space 前缀及其local-name 后的冒号后不应有space。例如。 niwa: events 应该是 niwa:events 等。其他
没有 niwa:References 的文本 children。

不确定您的最终目标是什么，但是这段代码，

import xml.etree.ElementTree as et

data = "" # As specified in question.

root = et.fromstring(data)
ns = {'exist':'http://exist.sourceforge.net/NS/exist',
      'niwa':'http://hwe.niwa.co.nz/schema/2011'}

for ref in root.findall('.//niwa:Title', ns):
  print('Title='+ref.text)

将演示成功选择namespaced XML中的文本，并输出：

Title= November 2019 Timaru Hail
Title=Insurance Council of New Zealand (https://www.icnz.org.nz/natural-disasters/cost-of-natural-disasters/)
Title=Headline:  Giant hail stones hammer Timaru as storm moves up the country.
Title=Headline:  Insurance companies face deluge of hail damage claims.
Title=Headline:  Cars damaged in severe Timaru hailstorm failing warrents of fitness.
Title=Headline:  Record insurance repairs for cars smashed by hail in Timaru.

Python 3x : 使用 python xml.etree 解析带有命名空间的 xml 文件

Python 3x : Parse an xml file with namespaces using python xml.etree

python

python-3.x

xml

xml-parsing

xml-namespaces