添加新的元素到XML使用ElementTree的

Question

我有以下的XML结构。（这是它的一部分）。实际上却TVEpisode”，‘TVShow’，‘电影’，‘TVSeries’，‘TVSeason’，我需要去通过XML文件并检查能解密元素。如果它不存在，需要根据上述类型的添加说明元件（mvoes，TVseries等）和插入影片，tvepisode等作为说明书的标题。

<TVSeries> 
<Provider>xxx</Provider> 
<Title>The World's Fastest Indian</Title> 
<Description> The World's Fastest Indian </Description> 
<SortTitle>World's Fastest Indian, The</SortTitle> 
</TvSeries> 

<Movies> 
<Provider>xxx</Provider> 
<Title>The World's Fastest Indian</Title> 
<Description> The World's Fastest Indian </Description> 
<SortTitle>World's Fastest Indian, The</SortTitle> 
</Movies> 

<TVShow> 
<Provider>xxx</Provider> 
<Title>The World's Fastest Indian</Title> 
<SortTitle>World's Fastest Indian, The</SortTitle> 
</TvShow> 

在tvshow没有描述元素，所以我需要插入以下到：

<Description> The World's Fastest Indian </Description> 

部分的XML文件：

<Feed xml:base="http://schemas.yyyy.com/xxxx/2011/06/13/ingestion" xmlns="http://schemas.yyy.com/xxxx/2011/06/13/ingestion"> 
<Movie> 
<Provider>xxx2</Provider> 
<Title>The World's Fastest Indian</Title> 
<SortTitle>World's Fastest Indian, The</SortTitle> 
</Movie> 
<TVSeries> 
<Provider>xxx</Provider> 
<Title>The World's Fastest Indian</Title> 
<Description> The World's Fastest Indian </Description> 
<SortTitle>World's Fastest Indian, The</SortTitle> 
</TvSeries> 

我需要步行通过xml文件并且需要插入元素“description”，如果描述不存在（并且还需要在描述中添加一些文本）。

这是我done.this可以给我这没有说明的标题。但是，当我尝试插入元素的结构它给了我下面的错误：

File "/usr/lib/python2.4/site-packages/elementtree/ElementTree.py", line 293, in insert 
    assert iselement(element) 
    AssertionError 

代码：

import elementtree.ElementTree as ET 
import sys 
import re 
output_namespace='http://schemas.yyy.com/xxx/2011/06/13/ingestion' 

types_to_remove=['TVEpisode','TVShow','Movie','TVSeries','TVSeason'] 

if ET.VERSION[0:3] == '1.2': 
#in ET < 1.3, this is a workaround for supressing prefixes 
def fixtag(tag, namespaces): 
    import string 
    # given a decorated tag (of the form {uri}tag), return prefixed 
    # tag and namespace declaration, if any 
    if isinstance(tag, ET.QName): 
     tag = tag.text 
    namespace_uri, tag = string.split(tag[1:], "}", 1) 
    prefix = namespaces.get(namespace_uri) 
    if namespace_uri not in namespaces: 
     prefix = ET._namespace_map.get(namespace_uri) 
     if namespace_uri not in ET._namespace_map: 
      prefix = "ns%d" % len(namespaces) 
     namespaces[namespace_uri] = prefix 
     if prefix == "xml": 
      xmlns = None 
     else: 
      if prefix is not None: 
       nsprefix = ':' + prefix 
      else: 
       nsprefix = '' 
      xmlns = ("xmlns%s" % nsprefix, namespace_uri) 
    else: 
     xmlns = None 
    if prefix is not None: 
     prefix += ":" 
    else: 
     prefix = '' 

    return "%s%s" % (prefix, tag), xmlns 

ET.fixtag = fixtag 
ET._namespace_map[output_namespace] = None 
else: 
    #For ET > 1.3, use register_namespace function 
     ET.register_namespace('', output_namespace) 



def descriptionAdd(root,type): 
    for child in root.findall('.//{http://schemas.yyy.com/xxx/2011/06/13/ingestion}%s' % type): 
     title=child.find('.//{http://schemas.yyy.com/xxx/2011/06/13/ingestion}Title').text 
     try: 
       if child.find('.//{http://schemas.yyy.com/xxx/2011/06/13 /ingestion}Description').text=="": 
       print("") 
     except: 
      print ' %s - couldn\'t find description' % (title) 
      print(child.tag) 
      child.insert(2,"Description") 

####Do the actual work and writing new changes to the new xml file. 

    tree = ET.parse(sys.argv[1]) 
    root = tree.getroot() 
    for type in types_to_remove: 

      descriptionAdd(root,type) 

    tree.write(sys.argv[2]) 

Answer 1

更新

我看你现在想要什么，我想。以下是我将如何做到这一点。请注意，您需要将其应用于包含电影，电视节目等的父元素。另请注意，该情况很重要（请参阅下面的代码中的注释）。

一，功能：

def insert_description(element): 
    '''Inserts the Title as a Description if Desscription not present.''' 
    for sub_e in element: 
     if sub_e.find('Description') is None: 
      title = sub_e.find('Title').text 
      new_desc = ET.Element('Description') 
      new_desc.text = title 
      sub_e.insert(2, new_desc) 

现在来测试功能：

>>> xml = ''' 
<Root> 
<Movie> 
    <Provider>xxx2</Provider> 
    <Title>The World's Fastest Indian</Title> 
    <SortTitle>World's Fastest Indian, The</SortTitle> 
</Movie> 
<TVSeries> 
    <Provider>xxx</Provider> 
    <Title>The World's Fastest Indian</Title> 
    <Description> The World's Fastest Indian </Description> 
    <SortTitle>World's Fastest Indian, The</SortTitle> 
    </TVSeries> // note that I changed the v to an upper-case V 
</Root>''' 
>>> root = ET.fromstring(xml) 
>>> insert_description(root) 
>>> print ET.tostring(root) 
<Root> 
<Movie> 
    <Provider>xxx2</Provider> 
    <Title>The World's Fastest Indian</Title> 
    <Description>The World's Fastest Indian</Description> 
    <SortTitle>World's Fastest Indian, The</SortTitle> 
</Movie> 
<TVSeries> 
    <Provider>xxx</Provider> 
    <Title>The World's Fastest Indian</Title> 
    <Description> The World's Fastest Indian </Description> 
    <SortTitle>World's Fastest Indian, The</SortTitle> 
</TVSeries> // note that I changed the v to an upper-case V 
</Root> 

我格式化与缩进后输出，以发生了什么事更清晰。