Question

对于一个项目，我应该增强一些XML并将其存储在一个文件中。我遇到的问题是我不断收到以下错误：

Traceback (most recent call last):
  File "C:\Python27\lib\multiprocessing\process.py", line 258, in _bootstrap
    self.run()
  File "C:\Python27\lib\multiprocessing\process.py", line 114, in run
    self._target(*self._args, **self._kwargs)
  File "C:\Users\Bart\Dropbox\Studie\2013-2014\BSc-KI\cite_parser\parser.py", line 193, in parse_references
    outputXML = ET.tostring(root, encoding='utf8', method='xml')
  File "C:\Python27\lib\xml\etree\ElementTree.py", line 1126, in tostring
    ElementTree(element).write(file, encoding, method=method)
  File "C:\Python27\lib\xml\etree\ElementTree.py", line 820, in write
    serialize(write, self._root, encoding, qnames, namespaces)
  File "C:\Python27\lib\xml\etree\ElementTree.py", line 939, in _serialize_xml
    _serialize_xml(write, e, encoding, qnames, None)
  File "C:\Python27\lib\xml\etree\ElementTree.py", line 939, in _serialize_xml
    _serialize_xml(write, e, encoding, qnames, None)
  File "C:\Python27\lib\xml\etree\ElementTree.py", line 939, in _serialize_xml
    _serialize_xml(write, e, encoding, qnames, None)
 ECLI:NL:RVS:2012:BY1564
 File "C:\Python27\lib\xml\etree\ElementTree.py", line 937, in _serialize_xml
    write(_escape_cdata(text, encoding))
  File "C:\Python27\lib\xml\etree\ElementTree.py", line 1073, in _escape_cdata
    return text.encode(encoding, "xmlcharrefreplace")
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 80: ordinal not in range(128)

该错误产生于：

outputXML = ET.tostring(root, encoding='utf8', method='xml')

在寻找这个问题的解决方案时，我发现了一些建议，说我应该在函数中添加.decode('utf-8')，但这会导致写入函数出现编码错误（首先是解码），这样就无法正常工作...

编码错误：

Traceback (most recent call last):
  File "C:\Python27\lib\multiprocessing\process.py", line 258, in _bootstrap
    self.run()
  File "C:\Python27\lib\multiprocessing\process.py", line 114, in run
    self._target(*self._args, **self._kwargs)
  File "C:\Users\Bart\Dropbox\Studie\2013-2014\BSc-KI\cite_parser\parser.py", line 197, in parse_references
    myfile.write(outputXML)
UnicodeEncodeError: 'ascii' codec can't encode character u'\xeb' in position 13559: ordinal not in range(128)

它由以下代码生成：

outputXML = ET.tostring(root, encoding='utf8', method='xml').decode('utf-8')

来源（或至少相关部分）：

# URL encodes the parameters
encoded_parameters = urllib.urlencode({'id':ecli})

# Opens XML file
feed = urllib2.urlopen("http://data.rechtspraak.nl/uitspraken/content?"+encoded_parameters, timeout = 3)

# Parses the XML
ecliFile = ET.parse(feed)

# Fetches root element of current tree
root = ecliFile.getroot()

# Write the XML to a file without any extra indents or newlines
outputXML = ET.tostring(root, encoding='utf8', method='xml')

# Write the XML to the file
with open(file, "w") as myfile:
    myfile.write(outputXML)

最后但并非最不重要的是XML示例的URL：http://data.rechtspraak.nl/uitspraken/content?id=ECLI:NL:RVS:2012:BY1542

Answer 1

异常是由字节字符串值引起的。

回溯中的

text应该是一个unicode值，但如果它是一个普通的字节字符串，Python将隐式地首先将它（使用ASCII编解码器）解码为Unicode，这样你就可以再次编码。

解码失败了。

因为您没有真正向我们展示您在XML树中插入的内容，所以除了确保在插入文本时始终使用Unicode值时，很难告诉您要修复的内容。

演示：

>>> root.attrib['oops'] = u'Data with non-ASCII codepoints \u2014 (em dash)'.encode('utf8')
>>> ET.tostring(root, encoding='utf8', method='xml')
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/Users/mj/Development/Library/buildout.python/parts/opt/lib/python2.7/xml/etree/ElementTree.py", line 1126, in tostring
    ElementTree(element).write(file, encoding, method=method)
  File "/Users/mj/Development/Library/buildout.python/parts/opt/lib/python2.7/xml/etree/ElementTree.py", line 820, in write
    serialize(write, self._root, encoding, qnames, namespaces)
  File "/Users/mj/Development/Library/buildout.python/parts/opt/lib/python2.7/xml/etree/ElementTree.py", line 932, in _serialize_xml
    v = _escape_attrib(v, encoding)
  File "/Users/mj/Development/Library/buildout.python/parts/opt/lib/python2.7/xml/etree/ElementTree.py", line 1090, in _escape_attrib
    return text.encode(encoding, "xmlcharrefreplace")
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 31: ordinal not in range(128)
>>> root.attrib['oops'] = u'Data with non-ASCII codepoints \u2014 (em dash)'
>>> ET.tostring(root, encoding='utf8', method='xml')
'<?xml version=\'1.0\' encoding=\'utf8\'?> ...'

设置包含ASCII范围之外的字节的bytestring属性会触发异常;使用unicode值可以确保产生结果。

ElementTree Unicode编码/解码错误

1 个答案: