Mailman 3 July 2013 - lxml - The Python XML Toolkit

[lxml-dev] lxml has its page on launchpad
by Stefan Behnel 11 Apr '23

11 Apr '23

Hi all, I added the lxml project to launchpad, the Ubuntu Bug-Tracker. It also has a FAQ engine and a couple of other goodies. https://launchpad.net/lxml It's easy to sign up for launchpad, BTW, no 90%-footnotes-contract. Have fun, Stefan

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[lxml-dev] Checking whether a node is a comment/element
by Geoffrey Sneddon 10 Apr '23

10 Apr '23

Hi, What's the best way to check whether a given node is a comment or an element? For the former, I'm currently using isinstance(node, etree._Comment), which is rather obviously sub-optimal. -- Geoffrey Sneddon <http://gsnedders.com/>

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[lxml-dev] Reparenting a node
by Lawrence Oluyede 30 Jan '23

30 Jan '23

I have a doc A and a doc B, I'd like to put a node extracted from A in the document B but I always get a ValueError: ValueError: Element is not a child of this node. I didn't find any "setparent" in the API. How can I do this? -- Lawrence, oluyede.org - neropercaso.it "It is difficult to get a man to understand something when his salary depends on not understanding it" - Upton Sinclair

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[lxml-dev] lxml 2.0.5 released
by Stefan Behnel 11 Jan '23

11 Jan '23

Hi all, lxml 2.0.5 is on PyPI. This is a bug-fix-only release of the stable 2.0 series. Have fun, Stefan 2.0.5 (2008-05-01) Bugs fixed * Resolving to a filename in custom resolvers didn't work. * lxml did not honour libxslt's second error state "STOPPED", which let some XSLT errors pass silently. * Memory leak in Schematron with libxml2 >= 2.6.31.

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[lxml-dev] Building LXML Trunk
by Sidnei da Silva 31 Aug '22

31 Aug '22

Hi, I've tried to build lxml from trunk today, on Win32. Got the following error: src\lxml\etree.c(880) : error C2059: syntax error : ')' src\lxml\etree.c(881) : error C2059: syntax error : ')' src\lxml\etree.c(882) : error C2059: syntax error : ')' src\lxml\etree.c(883) : error C2059: syntax error : ')' Any clue? Smells like a Pyrex issue? -- Sidnei da Silva Enfold Systems http://enfoldsystems.com Fax +1 832 201 8856 Office +1 713 942 2377 Ext 214

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lxml.objectify drops leading whitespace
by Wolfgang Schnerring 02 Oct '13

02 Oct '13

Hello, lxml.objectify drops leading whitespace before a tag: >>> lxml.etree.tostring(lxml.objectify.fromstring(' <a>foo</a>')) '<a>foo</a>' while lxml.etree handles the same situation just fine: >>> lxml.etree.tostring(lxml.etree.fromstring(' <a>foo</a>')) ' <a>foo</a>' What's the reason for the different behaviour? Is this intentional? Most importantly, how can I make lxml.objectify preserve whitespace correctly? Thanks for your help, Wolfgang

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Problems using LXML with Mod WSGI
by Lee E. Brown 12 Aug '13

12 Aug '13

Greetings! I am using Apache 2.2.25, Mod WSGI 3.3, LXML 3.2.1, and Python 2.7.2 My web site scheme stores web pages as XML documents which are transformed into XHTML on-the-fly using XSLT. Previously I had been using a mod_python output filter and I am now trying to update my system to use mod_wsgi. I have converted the mod_python output filter into an equivalent mod_wsgi script as shown below. This script when run outside of mod_wsgi functions perfectly. When it is run inside mod_wsgi it goes into the etree.XSLT() method on line 57 and there it hangs up until Apache times out the request. No information is written to the errorlog files. I have gone through all the known application issues and debugging suggestions given on the mod_wsgi wikki to no avail. Any help at this point would be greatly appreciated. """ Transform an XML document into an XHTML document """ import sys, os, time from cStringIO import StringIO sys.path.append('C:/webroot/sites/wsgitest/wsgiscripts') sys.path.append('C:/webroot/sites/wsgitest/content') sys.path.append('C:/Python27/lib/site-packages/lxml') from lxml import etree from fileutils import * from nsutils import * ns = {'pysite': 'http://www.leebrown.org/pysite'} def paramify (parent, target={}): """ A very quick and dirty objectification function. Given an arbitrary parent etree element, creates a dictionary of {local-name:text} from each child element. Also adds necessary embedded quotes to make the dictionary suitable to pass as XSLT parameters. Requires function lname() from module nsutils.py """ for child in parent.getchildren(): target[lname(child.tag)] = "'%s'" % (child.text) return target def parse_source (streambuffer): """ Converts the source XML held in streambuffer into an lxml Element Tree. Source includes are also processed at this time. """ streambuffer.seek(0) xml_tree = etree.parse(streambuffer, etree.XMLParser(remove_blank_text=True)) xml_tree.xinclude() return xml_tree def parse_template (xml_tree): """ Attempts to create an XSLT transform object from an xml-stylesheet PI in the source tree. Returns a None object if no xml-stylesheet PI is found; this causes the transform() function below to return untransformed XML to the client. """ xsl_pi = xml_tree.getroot().getprevious() xsl_tree = xsl_pi.parseXSL() if xsl_tree: return etree.XSLT(xsl_tree) else: return None def get_params (xml_tree): """ If the source XML contains a <page-params> element in the target namespace, convert all child elements of this element into an XLST parameter dictionary. Other parameters may be added on as desired. """ try: params = paramify(xml_tree.xpath('//pysite:page-params', namespaces=ns)[0]) except IndexError: params = {} return params def transform (streambuffer): """ This is where most of the fun stuff happens. If parse_template() returns a transformer object, the source XML tree is transformed, and any xincludes added in the transform are then processed. If parse template() does not return a tranformer object, this function returns the unparsed, untransformed XML source. """ xml_tree = parse_source(streambuffer) transformer = parse_template(xml_tree) if transformer: params = get_params(xml_tree) result_tree = transformer(xml_tree, **params) result_tree.xinclude() return result_tree else: return streambuffer.getvalue() def parse_request(environ): path = environ['PATH_INFO'].lstrip('/') filespec = smoothpath('C:/webroot/sites/wsgitest/content', path, 'page.xml') return filespec def application(environ,start_response): start = time.clock() buffer = StringIO() try: buffer.write(readfile(parse_request(environ))) result_tree = transform(buffer) end = time.clock() try: # Looks for %f and %i in output, inserts transform time # and pages per second if found result = str(result_tree) % (float(end - start), int(1.0/(end - start))) except: result = str(result_tree) status = '200 OK' except IOError: status = '404 FILE NOT FOUND' result = '404 FILE NOT FOUND' finally: # Prepare HTTP response response_headers = [('Content-Type','text/html'),('Content-Length',str(len(result)))] start_response(status,response_headers) return([result]) if __name__ == '__main__': def start_response(status, response_headers): pass environ = {} environ['PATH_INFO'] = '/' result = application(environ, start_response) for line in result: print line -- Best Regards, Lee E. Brown

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Htmldiff stripping newlines from pre tags
by Tom . 01 Aug '13

01 Aug '13

Hello, I'm using lxml's htmldiff function to (surprise) diff two HTML snippets. However I have found that if the snippet includes a <pre> tag then any newlines are stripped from it. For example: >>> html = "<pre>test\ntest2\ntest3</pre>" >>> print repr(htmldiff(html, html)) u'<pre>test test2 test3</pre>' Is there a reason for this, or better yet is there a way I can stop this from occurring? I was under the impression that inside a pre tag newlines and whitespace are handled differently and shouldn't be stripped like you can do with other HTML tags. Tom

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When writing to file, all ElementTrees are accumulated
by Jasper Timmer 30 Jul '13

30 Jul '13

Hi, I try to diff some files in a company internal xml format via lxml, and write the diff as xml back to disk. I do a double diff: file1+file2, and file3+file2, and then I diff the two diff files again and write that back to disk. I'm not using the html diff, I do the works myself. In the end I do: etree.ElementTree(diff1).write("diff1.xml", pretty_print=True, xml_declaration=True) etree.ElementTree(diff2).write("diff2.xml", pretty_print=True, xml_declaration=True) result.addprevious(etree.PI('xml-stylesheet', 'type="text/xsl" href="uberdiff.xsl"')) resultTree = etree.ElementTree(result) resultTree.write("Udiff.xml", pretty_print=True, xml_declaration=True) On inspection, the root of diff2 contains the children of the root of diff1 + his own children, and Udiff contains the children of diff2 (including those of diff1!) and his own. I am trying to debug this for days, I can't really find it yet. I'm wondering if I'm leaking this myself or that there is a bug or internal thing in lxml that I do not understand yet. Please inspect my code on: https://github.com/Y3PP3R/difftooling I'm working with python 2.7.3 32bit on windows 7 x64 and the lxml binaries 2.3. from http://www.lfd.uci.edu/~gohlke/pythonlibs/#lxml Thank for any pointers in the right direction already. Jasper Timmer

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lxml 3.2.2 released
by Stefan Behnel 28 Jul '13

28 Jul '13

Hi everyone, I just sent out lxml 3.2.2 as a bug-fix release for the stable 3.2 release series. You can get it from PyPI: http://pypi.python.org/pypi/lxml/3.2.2 The documentation is here: http://lxml.de/ Download: http://lxml.de/files/lxml-3.2.2.tgz Signature: http://lxml.de/files/lxml-3.2.2.tgz.asc Changelog: http://lxml.de/3.2/changes-3.2.2.html GitHub: https://github.com/lxml/lxml/commit/8c59378b76732a9082a76da1467f8f40b54c2920 This release was built using Cython 0.19.1. Note that the build no longer uses Cython, even if it is installed. Recompilation of the sources has to be requested explicitly with the setup.py option "--with-cython". If you are interested in commercial support or customisations for the lxml package, please contact me directly. Have fun, Stefan 3.2.2 (2013-07-28) ================== Features added -------------- Bugs fixed ---------- * LP#1185701: spurious XMLSyntaxError after finishing iterparse(). * Crash in lxml.objectify during xsi annotation. Other changes ------------- * Return values of user provided element class lookup methods are now validated against the type of the XML node they represent to prevent API class mismatches.

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