python - xmltodict 将非类型输出转换为列表

Question

我有一个来自 xmltodict 的基本示例，它与项目 github 页面上给出的示例非常相似。

def handle(_, book):
    print(book['title'])
    return True

with open(r'C:\Users\u369811\books.xml', 'r') as f:
    FILE = f.read()
    OUTPUT = xmltodict.parse((FILE), item_depth=2, item_callback=handle)
    print(OUTPUT)

对于这个 xml

<?xml version="1.0"?>
<catalog>
   <book id="bk101">
      <author>Gambardella, Matthew</author>
      <title>XML Developer's Guide</title>
      <genre>Computer</genre>
      <price>44.95</price>
      <publish_date>2000-10-01</publish_date>
      <description>An in-depth look at creating applications 
      with XML.</description>
   </book>
   <book id="bk102">
      <author>Ralls, Kim</author>
      <title>Midnight Rain</title>
      <genre>Fantasy</genre>
      <price>5.95</price>
      <publish_date>2000-12-16</publish_date>
      <description>A former architect battles corporate zombies, 
      an evil sorceress, and her own childhood to become queen 
      of the world.</description>
   </book>
   <book id="bk103">
      <author>Corets, Eva</author>
      <title>Maeve Ascendant</title>
      <genre>Fantasy</genre>
      <price>5.95</price>
      <publish_date>2000-11-17</publish_date>
      <description>After the collapse of a nanotechnology 
      society in England, the young survivors lay the 
      foundation for a new society.</description>
   </book>
   <book id="bk104">
      <author>Corets, Eva</author>
      <title>Oberon's Legacy</title>
      <genre>Fantasy</genre>
      <price>5.95</price>
      <publish_date>2001-03-10</publish_date>
      <description>In post-apocalypse England, the mysterious 
      agent known only as Oberon helps to create a new life 
      for the inhabitants of London. Sequel to Maeve 
      Ascendant.</description>
   </book>
   <book id="bk105">
      <author>Corets, Eva</author>
      <title>The Sundered Grail</title>
      <genre>Fantasy</genre>
      <price>5.95</price>
      <publish_date>2001-09-10</publish_date>
      <description>The two daughters of Maeve, half-sisters, 
      battle one another for control of England. Sequel to 
      Oberon's Legacy.</description>
   </book>
   <book id="bk106">
      <author>Randall, Cynthia</author>
      <title>Lover Birds</title>
      <genre>Romance</genre>
      <price>4.95</price>
      <publish_date>2000-09-02</publish_date>
      <description>When Carla meets Paul at an ornithology 
      conference, tempers fly as feathers get ruffled.</description>
   </book>
   <book id="bk107">
      <author>Thurman, Paula</author>
      <title>Splish Splash</title>
      <genre>Romance</genre>
      <price>4.95</price>
      <publish_date>2000-11-02</publish_date>
      <description>A deep sea diver finds true love twenty 
      thousand leagues beneath the sea.</description>
   </book>
   <book id="bk108">
      <author>Knorr, Stefan</author>
      <title>Creepy Crawlies</title>
      <genre>Horror</genre>
      <price>4.95</price>
      <publish_date>2000-12-06</publish_date>
      <description>An anthology of horror stories about roaches,
      centipedes, scorpions  and other insects.</description>
   </book>
   <book id="bk109">
      <author>Kress, Peter</author>
      <title>Paradox Lost</title>
      <genre>Science Fiction</genre>
      <price>6.95</price>
      <publish_date>2000-11-02</publish_date>
      <description>After an inadvertant trip through a Heisenberg
      Uncertainty Device, James Salway discovers the problems 
      of being quantum.</description>
   </book>
   <book id="bk110">
      <author>O'Brien, Tim</author>
      <title>Microsoft .NET: The Programming Bible</title>
      <genre>Computer</genre>
      <price>36.95</price>
      <publish_date>2000-12-09</publish_date>
      <description>Microsoft's .NET initiative is explored in 
      detail in this deep programmer's reference.</description>
   </book>
   <book id="bk111">
      <author>O'Brien, Tim</author>
      <title>MSXML3: A Comprehensive Guide</title>
      <genre>Computer</genre>
      <price>36.95</price>
      <publish_date>2000-12-01</publish_date>
      <description>The Microsoft MSXML3 parser is covered in 
      detail, with attention to XML DOM interfaces, XSLT processing, 
      SAX and more.</description>
   </book>
   <book id="bk112">
      <author>Galos, Mike</author>
      <title>Visual Studio 7: A Comprehensive Guide</title>
      <genre>Computer</genre>
      <price>49.95</price>
      <publish_date>2001-04-16</publish_date>
      <description>Microsoft Visual Studio 7 is explored in depth,
      looking at how Visual Basic, Visual C++, C#, and ASP+ are 
      integrated into a comprehensive development 
      environment.</description>
   </book>
</catalog>

这可以很好地打印出所有书籍，但是，书名是 NoneType，我无法迭代输出或将它们强制到列表中。

如何将返回的输出作为字符串列表？

Answer 1

我对 xmltodict 也有类似的问题，所以我修改了 this片段，这是我得到的:

#!/usr/bin/env python3
# -*- coding: utf8 -*-
import xml.etree.cElementTree as ElementTree


class Parser:

    def __init__(self, file):
        self.root = ElementTree.parse(file).getroot()

    class Dict(dict):

        def __init__(self, parent_element, **kwargs):
            super().__init__(**kwargs)
            if parent_element.items():
                self.update(dict(parent_element.items()))
            for element in parent_element:
                if element:
                    # treat like dict - we assume that if the first two tags
                    # in a series are different, then they are all different.
                    if len(element) == 1 or element[0].tag != element[1].tag:
                        item = Parser.Dict(element)
                    # treat like list - we assume that if the first two tags
                    # in a series are the same, then the rest are the same.
                    else:
                        # here, we put the list in dictionary; the key is the
                        # tag name the list elements all share in common, and
                        # the value is the list itself
                        item = {element[0].tag: Parser.List(element)}
                    # if the tag has attributes, add those to the dict
                    if element.items():
                        item.update(dict(element.items()))
                    self.update({element.tag: item})
                # this assumes that if you've got an attribute in a tag,
                # you won't be having any text. This may or may not be a
                # good idea -- time will tell. It works for the way we are
                # currently doing XML configuration files...
                elif element.items():
                    self.update({element.tag: dict(element.items())})
                # finally, if there are no child tags and no attributes, extract
                # the text
                else:
                    self.update({element.tag: element.text})

    class List(list):
        def __init__(self, item):
            super().__init__()
            for element in item:
                if element:
                    # treat like dict
                    if len(element) == 1 or element[0].tag != element[1].tag:
                        self.append(Parser.Dict(element))
                    # treat like list
                    elif element[0].tag == element[1].tag:
                        self.append(Parser.List(element))
                elif element.text:
                    text = element.text.strip()
                    if text:
                        self.append(text)
                elif element.items():
                    self.append(dict(element.items()))

    @property
    def parsed(self):
        if self.root.items():
            return Parser.Dict(self.root)
        else:
            return {self.root.tag: Parser.List(self.root)}

if __name__ == "__main__":
    import pprint
    pprint.pprint(Parser('PATH_TO_YOUR_XML.xml').parsed)

您的示例输出将是:

{'catalog': [{'author': 'Gambardella, Matthew',
              'description': 'An in-depth look at creating applications \n'
                             '      with XML.',
              'genre': 'Computer',
              'id': 'bk101',
              'price': '44.95',
              'publish_date': '2000-10-01',
              'title': "XML Developer's Guide"},
             {'author': 'Ralls, Kim',
              'description': 'A former architect battles corporate zombies, \n'
                             '      an evil sorceress, and her own childhood '
                             'to become queen \n'
                             '      of the world.',
              'genre': 'Fantasy',
              'id': 'bk102',
              'price': '5.95',
              'publish_date': '2000-12-16',
              'title': 'Midnight Rain'},
             {'author': 'Corets, Eva',
              'description': 'After the collapse of a nanotechnology \n'
                             '      society in England, the young survivors '
                             'lay the \n'
                             '      foundation for a new society.',
              'genre': 'Fantasy',
              'id': 'bk103',
              'price': '5.95',
              'publish_date': '2000-11-17',
              'title': 'Maeve Ascendant'},
             {'author': 'Corets, Eva',
              'description': 'In post-apocalypse England, the mysterious \n'
                             '      agent known only as Oberon helps to create '
                             'a new life \n'
                             '      for the inhabitants of London. Sequel to '
                             'Maeve \n'
                             '      Ascendant.',
              'genre': 'Fantasy',
              'id': 'bk104',
              'price': '5.95',
              'publish_date': '2001-03-10',
              'title': "Oberon's Legacy"},
             {'author': 'Corets, Eva',
              'description': 'The two daughters of Maeve, half-sisters, \n'
                             '      battle one another for control of England. '
                             'Sequel to \n'
                             "      Oberon's Legacy.",
              'genre': 'Fantasy',
              'id': 'bk105',
              'price': '5.95',
              'publish_date': '2001-09-10',
              'title': 'The Sundered Grail'},
             {'author': 'Randall, Cynthia',
              'description': 'When Carla meets Paul at an ornithology \n'
                             '      conference, tempers fly as feathers get '
                             'ruffled.',
              'genre': 'Romance',
              'id': 'bk106',
              'price': '4.95',
              'publish_date': '2000-09-02',
              'title': 'Lover Birds'},
             {'author': 'Thurman, Paula',
              'description': 'A deep sea diver finds true love twenty \n'
                             '      thousand leagues beneath the sea.',
              'genre': 'Romance',
              'id': 'bk107',
              'price': '4.95',
              'publish_date': '2000-11-02',
              'title': 'Splish Splash'},
             {'author': 'Knorr, Stefan',
              'description': 'An anthology of horror stories about roaches,\n'
                             '      centipedes, scorpions  and other insects.',
              'genre': 'Horror',
              'id': 'bk108',
              'price': '4.95',
              'publish_date': '2000-12-06',
              'title': 'Creepy Crawlies'},
             {'author': 'Kress, Peter',
              'description': 'After an inadvertant trip through a Heisenberg\n'
                             '      Uncertainty Device, James Salway discovers '
                             'the problems \n'
                             '      of being quantum.',
              'genre': 'Science Fiction',
              'id': 'bk109',
              'price': '6.95',
              'publish_date': '2000-11-02',
              'title': 'Paradox Lost'},
             {'author': "O'Brien, Tim",
              'description': "Microsoft's .NET initiative is explored in \n"
                             "      detail in this deep programmer's "
                             'reference.',
              'genre': 'Computer',
              'id': 'bk110',
              'price': '36.95',
              'publish_date': '2000-12-09',
              'title': 'Microsoft .NET: The Programming Bible'},
             {'author': "O'Brien, Tim",
              'description': 'The Microsoft MSXML3 parser is covered in \n'
                             '      detail, with attention to XML DOM '
                             'interfaces, XSLT processing, \n'
                             '      SAX and more.',
              'genre': 'Computer',
              'id': 'bk111',
              'price': '36.95',
              'publish_date': '2000-12-01',
              'title': 'MSXML3: A Comprehensive Guide'},
             {'author': 'Galos, Mike',
              'description': 'Microsoft Visual Studio 7 is explored in depth,\n'
                             '      looking at how Visual Basic, Visual C++, '
                             'C#, and ASP+ are \n'
                             '      integrated into a comprehensive '
                             'development \n'
                             '      environment.',
              'genre': 'Computer',
              'id': 'bk112',
              'price': '49.95',
              'publish_date': '2001-04-16',
              'title': 'Visual Studio 7: A Comprehensive Guide'}]}