Error 'failed to load external entity' when using Python lxml

elementtree, lxml, python, xml

Solution

In concert with what mzjn said, if you do want to pass a string to etree.parse(), just wrap it in a StringIO object.

Example (python2):

from lxml import etree
from StringIO import StringIO

myString = "<html><p>blah blah blah</p></html>"

tree = etree.parse(StringIO(myString))

Example (python3) import from `io` instead of `StringIO`:

from lxml import etree
from io import StringIO

myString = "<html><p>blah blah blah</p></html>"

tree = etree.parse(StringIO(myString))

This method is used in the lxml documentation.

Problem

I'm trying to parse an XML document I retrieve from the web, but it crashes after parsing with this error: ``` ': failed to load external entity "<?xml version="1.0" encoding="UTF-8"?> <?xml-stylesheet type="text/xsl" href="GreenButtonDataStyleSheet.xslt"?> ``` That is the second line in the XML that is downloaded. Is there a way to prevent the parser from trying to load the external entity, or another way to solve this? This is the code I have so far: ``` import urllib2 import lxml.etree as etree file = urllib2.urlopen("http://www.greenbuttondata.org/data/15MinLP_15Days.xml") data = file.read() file.close() tree = etree.parse(data) ```

Original source