使用lxml解析XML时出现问题

Question

我一直在尝试将XML提要解析为Pandas数据帧，但无法找出我要去哪里。

import pandas as pd
import requests
import lxml.objectify
path = "http://www2.cineworld.co.uk/syndication/listings.xml"

xml = lxml.objectify.parse(path)
root = xml.getroot()

代码的下一部分是解析我想要的部分，并创建显示词典列表。

shows_list = []
for r in root.cinema:
    rec = {}
    rec['name'] = r.attrib['name']
    rec['info'] = r.attrib["root"] + r.attrib['url']
    listing = r.find("listing")
    for f in listing.film:
        film = rec
        film['title'] = f.attrib['title']
        film['rating'] = f.attrib['rating']
        shows = f.find("shows")
        for s in shows['show']:
            show = rec
            show['time'] = s.attrib['time']
            show['url'] = s.attrib['url']
            #print show
            shows_list.append(rec)

df = pd.DataFrame(show_list)

当我运行代码时，电影和时间字段似乎在行中被多次复制。 但是，如果我在代码中添加了一条打印语句（已将其注释掉），则字典将如我所愿。

我究竟做错了什么？ 请随时让我知道是否还有更Python化的解析过程。

编辑：澄清：

如果我使用print语句检查遍历时发生的情况，则这些是数据的最后五行。

{'info': 'http://cineworld.co.uk/cinemas/107/information', 'rating': 'TBC', 'name': 'Cineworld Stoke-on-Trent', 'title': "Dad's Army", 'url': '/booking?performance=4729365&seats=STANDARD', 'time': '2016-02-07T20:45:00'}
{'info': 'http://cineworld.co.uk/cinemas/107/information', 'rating': 'TBC', 'name': 'Cineworld Stoke-on-Trent', 'title': "Dad's Army", 'url': '/booking?performance=4729366&seats=STANDARD', 'time': '2016-02-08T20:45:00'}
{'info': 'http://cineworld.co.uk/cinemas/107/information', 'rating': 'TBC', 'name': 'Cineworld Stoke-on-Trent', 'title': "Dad's Army", 'url': '/booking?performance=4729367&seats=STANDARD', 'time': '2016-02-09T20:45:00'}
{'info': 'http://cineworld.co.uk/cinemas/107/information', 'rating': 'TBC', 'name': 'Cineworld Stoke-on-Trent', 'title': "Dad's Army", 'url': '/booking?performance=4729368&seats=STANDARD', 'time': '2016-02-10T20:45:00'}
{'info': 'http://cineworld.co.uk/cinemas/107/information', 'rating': 'TBC', 'name': 'Cineworld Stoke-on-Trent', 'title': "Dad's Army", 'url': '/booking?performance=4729369&seats=STANDARD', 'time': '2016-02-11T20:45:00'}
{'info': 'http://cineworld.co.uk/cinemas/107/information', 'rating': 'PG', 'name': 'Cineworld Stoke-on-Trent', 'title': 'Autism Friendly Screening - Goosebumps', 'url': '/booking?performance=4782937&seats=STANDARD', 'time': '2016-02-07T11:00:00'}

这是列表的结尾：...

{'info': 'http://cineworld.co.uk/cinemas/107/information',
  'name': 'Cineworld Stoke-on-Trent',
  'rating': 'PG',
  'time': '2016-02-07T11:00:00',
  'title': 'Autism Friendly Screening - Goosebumps',
  'url': '/booking?performance=4782937&seats=STANDARD'},
 {'info': 'http://cineworld.co.uk/cinemas/107/information',
  'name': 'Cineworld Stoke-on-Trent',
  'rating': 'PG',
  'time': '2016-02-07T11:00:00',
  'title': 'Autism Friendly Screening - Goosebumps',
  'url': '/booking?performance=4782937&seats=STANDARD'},
 {'info': 'http://cineworld.co.uk/cinemas/107/information',
  'name': 'Cineworld Stoke-on-Trent',
  'rating': 'PG',
  'time': '2016-02-07T11:00:00',
  'title': 'Autism Friendly Screening - Goosebumps',
  'url': '/booking?performance=4782937&seats=STANDARD'},
 {'info': 'http://cineworld.co.uk/cinemas/107/information',
  'name': 'Cineworld Stoke-on-Trent',
  'rating': 'PG',
  'time': '2016-02-07T11:00:00',
  'title': 'Autism Friendly Screening - Goosebumps',
  'url': '/booking?performance=4782937&seats=STANDARD'}]

Answer 1

您的代码只有一个不断更新的对象： rec 。 尝试这个：

from copy import copy
shows_list = []
for r in root.cinema:
    rec = {}
    rec['name'] = r.attrib['name']
    rec['info'] = r.attrib["root"] + r.attrib['url']
    listing = r.find("listing")
    for f in listing.film:
        film = copy(rec) # New object
        film['title'] = f.attrib['title']
        film['rating'] = f.attrib['rating']
        shows = f.find("shows")
        for s in shows['show']:
            show = copy(film) # New object, changed reference
            show['time'] = s.attrib['time']
            show['url'] = s.attrib['url']
            #print show
            shows_list.append(show) # Changed reference

df = pd.DataFrame(show_list)

利用这种结构，在数据rec被复制到每个film ，并且在每个数据film被复制到每个show 。 然后，最后将show添加到shows_list 。

您可能需要阅读这篇文章，以了解更多有关line film = rec ，即您film = rec原始字典起另一个名字，而不是创建一个新的字典。