lxml etree解析失败(IOError)

Question

我在试着运行这个程序。直到今天都很好。在我的代码中没有任何改变。

import lxml.etree
import urlparse
import re

def parse_url(url):
    return lxml.etree.parse(url, lxml.etree.HTMLParser())

urlivv = "http://finance.yahoo.com/q?s=IVV"
docivv = parse_url(urlivv)

这是我的错误信息：

IOError: Error reading file 'http://finance.yahoo.com/q?s=IVV': failed to load external entity "http://finance.yahoo.com/q?s=IVV"

站点上有一些关于将StringIO添加到参数中的文档(见下文)。但我觉得很奇怪我以前从没这么做过。

tree = etree.parse(StringIO(myString))

编辑:更完整的堆栈跟踪。

>>> import lxml.etree
>>> tree = lxml.etree.parse('http://finance.yahoo.com/q?s=IVV', parser=lxml.etree.HTMLParser())
Traceback (most recent call last):
  File "<interactive input>", line 1, in <module>
  File "src\lxml\lxml.etree.pyx", line 3427, in lxml.etree.parse (src\lxml\lxml.etree.c:81100)
  File "src\lxml\parser.pxi", line 1811, in lxml.etree._parseDocument (src\lxml\lxml.etree.c:117831)
  File "src\lxml\parser.pxi", line 1837, in lxml.etree._parseDocumentFromURL (src\lxml\lxml.etree.c:118178)
  File "src\lxml\parser.pxi", line 1741, in lxml.etree._parseDocFromFile (src\lxml\lxml.etree.c:117090)
  File "src\lxml\parser.pxi", line 1138, in lxml.etree._BaseParser._parseDocFromFile (src\lxml\lxml.etree.c:111636)
  File "src\lxml\parser.pxi", line 595, in lxml.etree._ParserContext._handleParseResultDoc (src\lxml\lxml.etree.c:105092)
  File "src\lxml\parser.pxi", line 706, in lxml.etree._handleParseResult (src\lxml\lxml.etree.c:106800)
  File "src\lxml\parser.pxi", line 633, in lxml.etree._raiseParseError (src\lxml\lxml.etree.c:105611)
OSError: Error reading file 'http://finance.yahoo.com/q?s=IVV': failed to load external entity "http://finance.yahoo.com/q?s=IVV"

Answer 1

如果你想找一个解释，你现在就可以停止阅读了。另一方面，如果你寻求一种补救，那么这可能就是它。

>>> page = requests.get('http://finance.yahoo.com/q?s=IVV').text
>>> lxml.etree.fromstring(page) #fails
>>> tree = lxml.etree.fromstring(page, parser=lxml.etree.HTMLParser())
>>> tree.xpath('.//table[@class="W(100%)"]')
[<Element table at 0x607dc08>]

简而言之，使用requests作为字符串获取页面，用lxml解析该字符串，然后像往常一样继续。

编辑:在运行此代码之前，您将需要import requests和import lxml.etree。