Suppressing namespace prefixes in ElementTree 1.2

Question

In python 2.7 (with etree 1.3), I can suppress the XML prefixes on elements like this:

Python 2.7.1 (r271:86832, Jun 16 2011, 16:59:05)  [GCC 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2335.15.00)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>> import xml.etree.ElementTree as etree >>> etree.VERSION '1.3.0' >>> something = etree.Element('{http://some.namespace}token') >>> etree.tostring(something) '<ns0:token xmlns:ns0="http://some.namespace" />' >>> etree.register_namespace('', 'http://some.namespace') >>> etree.tostring(something) '<token xmlns="http://some.namespace" />' 

The register_namespace function was added in 1.3. I'm trying to remove the prefix in a way that is compatible with python 2.6's etree at version 1.2.6. Here's what I've tried:

Python 2.6.7 (r267:88850, Jul 31 2011, 19:30:54)  [GCC 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2335.15.00)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>> import xml.etree.ElementTree as etree >>> etree.VERSION '1.2.6' >>> something = etree.Element('{http://some.namespace}token') >>> etree.tostring(something) '<ns0:token xmlns:ns0="http://some.namespace" />' >>> etree._namespace_map['http://some.namespace'] = '' >>> etree.tostring(something) '<:token xmlns:="http://some.namespace" />' 

This is not what I want. The prefixes are still there but are blank. Is there any way to remove them completely?

Answer 1

After looking at the source code for ElementTree in python2.6, the : is hard coded in the fixtag function. As a workaround, here's what I did:

from xml.etree import ElementTree as etree  if etree.VERSION[0:3] == '1.2':     #in etree < 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, etree.QName):             tag = tag.text         namespace_uri, tag = string.split(tag[1:], "}", 1)         prefix = namespaces.get(namespace_uri)         if namespace_uri not in namespaces:             prefix = etree._namespace_map.get(namespace_uri)             if namespace_uri not in etree._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      etree.fixtag = fixtag     etree._namespace_map['http://some.namespace'] = None else:     #For etree > 1.3, use register_namespace function     etree.register_namespace('', 'http://some.namespace') 

In case this post ever gets out of date, the code is maintained here.

Answer 2

I created a method at the top of my file and simply use it where the tag string should be. I named it 'ns_tag', but you could name it whatever you want.

def ns_tag(tag):     return str( ElementTree.QName('http://some.namespace/api/4/', tag) ) 

Example:

root = ElementTree.fromstring(xml) success = root.find(ns_tag('success')) if success.text == 'true':     for node in root.find(ns_tag('items')):         id = node.find(ns_tag('id')).text         ...