Question

我想循环浏览XML格式的Wikipedia转储，并且对于每个修订我想要保存时间戳和注释，如果修订是由某个用户名进行的。这可能吗？我试图熟悉lxml。

<mediawiki xmlns="http://www.mediawiki.org/xml/export-0.10/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.mediawiki.org/xml/export-0.10/ http://www.mediawiki.org/xml/export-0.10.xsd" version="0.10" xml:lang="en">
    <siteinfo>
        <sitename>Wikipedia</sitename>
        <dbname>enwiki</dbname>
        <base>https://en.wikipedia.org/wiki/Main_Page</base>
        <generator>MediaWiki 1.27.0-wmf.18</generator>
        <case>first-letter</case>
        <namespaces>...</namespaces>
    </siteinfo>
    <page>
        <title>Zhuangzi</title>
        <ns>0</ns>
        <id>42870472</id>
        <revision>
            <id>610251969</id>
            <timestamp>2014-05-26T20:08:14Z</timestamp>
            <contributor>
                <username>White whirlwind</username>
                <id>8761551</id>
            </contributor>
            <comment>...</comment>
            <model>wikitext</model>
            <format>text/x-wiki</format>
            <text xml:space="preserve" bytes="41">#REDIRECT [[Zhuang Zhou]] {{R from move}}</text>
            <sha1>9l31fcd4fp0cfxgearifr7jrs3240xl</sha1>
        </revision>
        <revision>...</revision>
        <revision>...</revision>
        <revision>...</revision>
        <revision>...</revision>
        <revision>...</revision>

    </page>
    <page>...</page>
</mediawiki>

Answer 1

是的，这可以使用lxml。

您知道要查找的节点（以reivision的用户名开头），因此请编写代码以选择该节点，并将该值与您要查找的已知名称进行比较。

完成该部分后，保存时间戳和注释应该很简单。

您将在lxml文档中找到所需内容（http://lxml.de/）;看看＆＃34; XPath＆＃34;找出如何选择你想要的节点（这将包括将XML加载到你的脚本中的片段）

您可能还希望查阅lxml链接（http://effbot.org/zone/element.htm）的ElementTree教程，以了解如何使用您将使用XPath或其他方法找到的XML元素。这对于从元素中获取值非常有用。

Answer 2

import xmltodict 


xml_input = """
<mediawiki xmlns="http://www.mediawiki.org/xml/export-0.10/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.mediawiki.org/xml/export-0.10/ http://www.mediawiki.org/xml/export-0.10.xsd" version="0.10" xml:lang="en">
<siteinfo>
    <sitename>Wikipedia</sitename>
    <dbname>enwiki</dbname>
    <base>https://en.wikipedia.org/wiki/Main_Page</base>
    <generator>MediaWiki 1.27.0-wmf.18</generator>
    <case>first-letter</case>
    <namespaces>...</namespaces>
</siteinfo>
<page>
    <title>Zhuangzi</title>
    <ns>0</ns>
    <id>42870472</id>
    <revision>
        <id>610251969</id>
        <timestamp>2014-05-25T20:08:14Z</timestamp>
        <contributor>
            <username>Patric</username>
            <id>8761551</id>
        </contributor>
    </revision>
    <revision>
        <id>610251969</id>
        <timestamp>2014-05-26T20:08:14Z</timestamp>
        <contributor>
            <username>Don</username>
            <id>8761551</id>
        </contributor>
    </revision>
    <revision>
        <id>610251969</id>
        <timestamp>2014-05-27T20:08:14Z</timestamp>
        <contributor>
            <username>Patric</username>
            <id>8761551</id>
        </contributor>
    </revision>                
</page>
</mediawiki>
"""


dic_xml = xmltodict.parse(xml_input)

for rev in dic_xml['mediawiki']['page']['revision']:
    if rev['contributor']['username'] == 'Patric':
        print rev['id']
        print rev['timestamp']

使用您的文件：

import xmltodict
with open('/home/jurkij/Downloads/testarticles.xml') as xml_file:
    dic_xml = xmltodict.parse(xml_file.read())
    for page in dic_xml['mediawiki']['page']:
        for rev in  page['revision']:
            if 'username' in rev['contributor'] and rev['contributor']['username'] == 'Aristophanes68':
                print rev['timestamp']
                print rev['id']

Answer 3

从last question继续，您可以使用 lxml 和xpath表达式轻松完成：

from lxml.etree import parse

tree = parse("test.xml")

ns = {"wiki": "http://www.mediawiki.org/xml/export-0.10/"}
revs = tree.xpath("//wiki:revision[.//wiki:username='White whirlwind']",namespaces=ns)

print([(rev.xpath(".//wiki:timestamp//text()", namespaces=ns)[0],rev.xpath(".//wiki:username//text()", namespaces=ns)[0]) for rev in revs])

对于以下xml：

<mediawiki xmlns="http://www.mediawiki.org/xml/export-0.10/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.mediawiki.org/xml/export-0.10/ http://www.mediawiki.org/xml/export-0.10.xsd" version="0.10" xml:lang="en">
    <siteinfo>
        <sitename>Wikipedia</sitename>
        <dbname>enwiki</dbname>
        <base>https://en.wikipedia.org/wiki/Main_Page</base>
        <generator>MediaWiki 1.27.0-wmf.18</generator>
        <case>first-letter</case>
        <namespaces>...</namespaces>
    </siteinfo>
    <page>
        <title>Zhuangzi</title>
        <ns>0</ns>
        <id>42870472</id>
        <revision>
            <id>610251969</id>
            <timestamp>2014-05-26T20:08:14Z</timestamp>
            <contributor>
                <username>White whirlwind</username>
                <id>8761551</id>
            </contributor>
            <comment>...</comment>
            <model>wikitext</model>
            <format>text/x-wiki</format>
            <text xml:space="preserve" bytes="41">#REDIRECT [[Zhuang Zhou]] {{R from move}}</text>
            <sha1>9l31fcd4fp0cfxgearifr7jrs3240xl</sha1>
        </revision>
        <revision>
                 <id>610251969</id>
            <timestamp>2014-06-26T20:08:14Z</timestamp>
            <contributor>
                <username>White whirlwind</username>
                <id>8761551</id>
            </contributor>
            <comment>...</comment>
            <model>wikitext</model>
            <format>text/x-wiki</format>
            <text xml:space="preserve" bytes="41">#REDIRECT [[Zhuang Zhou]] {{R from move}}</text>
            <sha1>9l31fcd4fp0cfxgearifr7jrs3240xl</sha1>
        </revision>
        <revision>     <id>610251969</id>
            <timestamp>2014-07-26T20:08:14Z</timestamp>
            <contributor>
                <username>foobar</username>
                <id>8761551</id>
            </contributor>
            <comment>...</comment>
            <model>wikitext</model>
            <format>text/x-wiki</format>
            <text xml:space="preserve" bytes="41">#REDIRECT [[Zhuang Zhou]] {{R from move}}</text>
            <sha1>9l31fcd4fp0cfxgearifr7jrs3240xl</sha1></revision>
        <revision>...</revision>
        <revision>...</revision>
        <revision>...</revision>

        </page>

输出：

 [[('2014-05-26T20:08:14Z', 'White whirlwind'), ('2014-06-26T20:08:14Z', 'White whirlwind')]

//wiki:revision[.//wiki:username='White whirlwind']找到包含用户名且用户名值为White whirlwind的所有修订代码，您会看到它返回2，因为foo不匹配，您只需要提取来自每个过滤修订版的时间戳和用户名值。

对于file in google drive，它会返回：

[('2014-05-26T20:08:14Z', 'White whirlwind'), 
('2014-05-26T20:12:49Z', 'White whirlwind'),
 ('2014-05-26T20:13:04Z', 'White whirlwind'),
('2014-05-31T21:14:15Z', 'White whirlwind'), 
('2015-10-11T19:24:46Z', 'White whirlwind'),
 ('2015-10-11T19:26:31Z', 'White whirlwind')]

如果你检查你的文件是正确的。

如果参数具有特定值，则从XML文件中提取数据

3 个答案: