如何使用iTunes ElementTree访问ElementTree中的值元素？

Question

我正在尝试将xml播放列表“导出”到html表以供共享。但是iTunes库文件使用一对键值，而不是更有意义的XML标记。是否有一种简单的方法也可以获得这些键/值对中的<value>？

这让我了解到了<key>的值，即轨道ID名、艺术家专辑艺术家等等，但是我似乎找不到一种方法也能得到下一个键的值，即<integer> 49924，或者<string> Ep。35你的..。我应该用ElementTree来完成这个任务吗?还是应该转到正则表达式或者其他库中呢？谢谢!

data = '''<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Major Version</key><integer>1</integer>
    <key>Minor Version</key><integer>1</integer>
    <key>Date</key><date>2019-01-21T07:31:15Z</date>
    <key>Application Version</key><string>12.8.0.150</string>
    <key>Features</key><integer>5</integer>
    <key>Show Content Ratings</key><true/>
    <key>Music Folder</key><string>file:///Users/Music/iTunes/iTunes%20Media/</string>
    <key>Library Persistent ID</key><string>75E62CF156F5AE1B</string>
    <key>Tracks</key>
    <dict>
        <key>49924</key>
        <dict>
            <key>Track ID</key><integer>49924</integer>
            <key>Name</key><string>Ep. 35 | What Do Your Morals Taste Like? | Guest: Jonathan Haidt</string>
            <key>Artist</key><string>Blaze Podcast Network</string>
            <key>Album Artist</key><string>Blaze Podcast Network</string>
            <key>Album</key><string>Something's Off with Andrew Heaton</string>
            <key>Genre</key><string>News &#38; Politics</string>
            <key>Kind</key><string>MPEG audio file</string>
            <key>Size</key><integer>48123940</integer>
            <key>Total Time</key><integer>3004133</integer>
            <key>Year</key><integer>2019</integer>
            <key>Date Modified</key><date>2019-01-13T01:10:30Z</date>
            <key>Date Added</key><date>2019-01-13T01:10:30Z</date>
            <key>Bit Rate</key><integer>128</integer>
            <key>Sample Rate</key><integer>44100</integer>
            <key>Release Date</key><date>2019-01-11T12:00:00Z</date>
            <key>Artwork Count</key><integer>1</integer>
            <key>Persistent ID</key><string>5FAE7186A09E5D3E</string>
            <key>Disabled</key><true/>
            <key>Track Type</key><string>File</string>
            <key>Purchased</key><true/>
            <key>Podcast</key><true/>
            <key>Unplayed</key><true/>
            <key>Location</key><string>file:///Users/Music/iTunes/iTunes%20Media/Podcasts/Something's%20Off%20with%20Andrew%20Heaton/Ep.%2035%20_%20What%20Do%20Your%20Morals%20Taste%20Like_%20_%20Guest_%20Jonathan%20Haidt.mp3</string>
            <key>File Folder Count</key><integer>4</integer>
            <key>Library Folder Count</key><integer>1</integer>
        </dict>
    </dict>
</dict>
</plist>'''
from xml.etree import ElementTree as ET
xml = ET.fromstring(data)
lst = xml.findall('dict/dict/dict/key')
for item in lst:
    print(item.text)

Answer 1

问题：如何访问iTunes xml中的值元素

下面使用lxml.etree.iterparse的解决方案将一个<key>标记附加到下面的<value>标记中，以构建<value> dict {key:value}。

已使用的模块和内置函数：

• lxml.etree.iterparse
• object.__iter__(self)
• 收益率表

from lxml import etree
import io

class Playlist:
    def __init__(self, fh):
        """
        Initialize 'iterparse' to generate 'start' and 'end' events on all tags

        :param fh: File Handle from the XML File to parse
        """
        self.context = etree.iterparse(fh, events=("start", "end",))

    def _parse(self):
        """
        Yield only at 'end' event, except 'start' from tag 'dict'
        :return: yield current Element
        """
        for event, elem in self.context:
            if elem.tag == 'plist' or \
                    (event == 'start' and not elem.tag == 'dict'):
                continue
            yield elem

    def _parse_key_value(self, key=None):
        _dict = {}
        for elem in self._parse():
            if elem.tag == 'key':
                key = elem.text
                continue

            if elem.tag in ['integer', 'string', 'date']:
                if not key is None:
                    _dict[key] = elem.text
                    key = None
                else:
                    print('Missing key for value {}'.format(elem.text))

            elif elem.tag in ['true', 'false']:
                _dict[key] = elem.tag == 'true'

            elif elem.tag == 'dict':
                if not key is None:
                    _dict[key] = self._parse_dict(key)
                    key = None
                else:
                    return elem, _dict
            else:
                print('Unknow tag {}'.format(elem.tag))

    def _parse_dict(self, key=None):
        elem = next(self._parse())
        elem, _dict = self._parse_key_value(elem.text)
        return _dict

    def __iter__(self):
        for elem in self._parse():
            if elem.tag == 'dict':
                yield self._parse_dict()
            else:
                print('Unknow tag {}'.format(elem.tag))

if __name__ == "__main__":

    data = b'''<?xml...'''

    with io.BytesIO(data) as in_xml:
        for record in Playlist(in_xml):
            print("record:{}".format(record))

            for key, value in record.items():
                print("{}:{}".format(key, value))

输出： 记录：{“主要版本”：“1”，“次要版本”：“1”主要版本:1个次要版本:1个日期:2019-01-24T10:31:15z曲目：{‘99244’：{‘轨道ID'：'99244'，’艺术家‘：’火焰播客网络‘，(为了简洁而省略)}}

用Python3.5测试：