Mailman 3 October 2010 - lxml - The Python XML Toolkit

[lxml-dev] lxml has its page on launchpad
by Stefan Behnel April 11, 2023

April 11, 2023

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 April 10, 2023

April 10, 2023

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 Jan. 30, 2023

Jan. 30, 2023

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 Jan. 11, 2023

Jan. 11, 2023

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 Aug. 31, 2022

Aug. 31, 2022

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-dev] confusing xpath performance characteristics
by jholg＠gmx.de Aug. 24, 2012

Aug. 24, 2012

Hi, I ran into some performance characteristics of lxml/libxml2 xpath that I find rather confusing: I try to find the @type attribute of a certain element in an XML Schema (which contains lots of complexType definitions with lots of elements in them; unfortunately I can't post the schema): >>> timeit.Timer(stmt="""xpath(schema)""", setup="""from lxml import etree, objectify; schema=etree.parse('NDM.xsd').getroot(); xpath = etree.XPath('//xs:element[@name="equity"]/@type', namespaces={'xs': 'http://www.w3.org/2001/XMLSchema'})""").repeat(number=10) [0.095885038375854492, 0.096823930740356445, 0.096174955368041992] So I think I'm being smart and give a little more path information - reckoning that this should *improve* performance: >>> timeit.Timer(stmt="""xpath(schema)""", setup="""from lxml import etree, objectify; schema=etree.parse('NDM.xsd').getroot(); xpath = etree.XPath('/xs:schema//xs:element[@name="equity"]/@type', namespaces={'xs': 'http://www.w3.org/2001/XMLSchema'})""").repeat(number=10) [0.1770780086517334, 0.1775970458984375, 0.17748594284057617] Hm. Performance degrades slightly. I'm adding even more of the path to where my desired elements live in the schema: >>> timeit.Timer(stmt="""xpath(schema)""", setup="""from lxml import etree, objectify; schema=etree.parse('xsd/NDM.xsd').getroot(); xpath = etree.XPath('/xs:schema/xs:complexType//xs:element[@name="equity"]/@type', namespaces={'xs': 'http://www.w3.org/2001/XMLSchema'})""").repeat(number=10) [103.79744100570679, 103.83671712875366, 103.61817717552185] What??? >>> timeit.Timer(stmt="""xpath(schema)""", setup="""from lxml import etree, objectify; schema=etree.parse('/ae/data/pydev/hjoukl/NDM/SVN_CO/TRUNK/ndm/reference/xsd/NDM.xsd').getroot(); xpath = etree.XPath('/xs:schema/xs:complexType/*/xs:element[@name="equity"]/@type', namespaces={'xs': 'http://www.w3.org/2001/XMLSchema'})""").repeat(number=10) [0.044407129287719727, 0.044126987457275391, 0.044229030609130859] >>> Ok, this version's better than my naive approach, which seems logical to me. But why would '/xs:schema/xs:complexType//xs:element[@name="equity"]/@type' perform drastically slower than '/xs:schema/xs:complexType//xs:element[@name="equity"]/@type' ? libxml2 problem? Running the same xpaths in Oxygen I don't notice performance differences (can't profile this). Holger -- GRATIS für alle GMX-Mitglieder: Die maxdome Movie-FLAT! Jetzt freischalten unter http://portal.gmx.net/de/go/maxdome01

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[lxml-dev] DLL issue with win32 static builds of lxml
by Scott Smith April 4, 2011

April 4, 2011

Hi I'm looking at upgrading our python installations from 2.6(.2) to 2.7 and upgrading the packages we use to the latest versions. We use python and the mod_wsgi module in Apache 2.2 for our application server and easy_install to install egg packages. I'm currently testing on a Windows 7 machine. The current egg version of lxml that we're using (before upgrading) is: lxml-2.2.4-py2.6-win32.egg In trying to upgrade things, I've found that all the later builds of lxml cause a DLL problem through apache. For example, all of these builds (from pipy) cause the problem: lxml-2.2.8-py2.6-win32.egg lxml-2.2.8-py2.7-win32.egg lxml-2.2beta1-py2.6-win32.egg lxml-2.3beta1-py2.6-win32.egg lxml-2.3beta1-py2.7-win32.egg (Note that there are no static win32 builds available for 2.2.5-2.2.7, or I can't find them) The error thrown in the Apache logs is: mod_wsgi (pid=4812): Target WSGI script 'C:/wsgi/handler.py' cannot be loaded as Python module. mod_wsgi (pid=4812): Exception occurred processing WSGI script 'C:/wsgi/handler.py'. Traceback (most recent call last): File "C:/wsgi/handler.py", line 2, in <module> from lxml import etree ImportError: DLL load failed: The specified module could not be found. The same file works in Python 2.6 if lxml 2.2.4 is installed, but fails for any other higher version of lxml (either in python 2.6 or 2.7). I've been able to trace the problem down to the builds not being able to find the msvcr90.dll file properly. I've tried modifying path variables and other changes, but can't figure out what the problem is. A couple of other things to note: - Using just "import lxml" doesn't cause the error, just "from lxml import etree" - The problem only occurs through Apache. If I write a script that references etree and call it through the command line, the problem doesn't occur. Does anyone know what I need to do? What changed after the 2.2.4 lxml builds? Thanks for any help you can give. Scott Smith

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[lxml-dev] SyntaxErrors with Python 3
by Arfrever Frehtes Taifersar Arahesis Nov. 23, 2010

Nov. 23, 2010

LXML r76211 generally supports Python 3, but there are still some SyntaxErrors. (The problem with ez_setup.py can be ignored.) $ python3.1 -m compileall -q . *** Error compiling ./benchmark/bench_etree.py ... File "./benchmark/bench_etree.py", line 10 UTEXT = u"some klingon: \F8D2" ^ SyntaxError: invalid syntax *** Error compiling ./benchmark/benchbase.py ... File "./benchmark/benchbase.py", line 10 _UTEXT = u"some klingon: \F8D2" * TREE_FACTOR ^ SyntaxError: invalid syntax *** Error compiling ./doc/mklatex.py ... File "./doc/mklatex.py", line 247 print "Creating %s" % outname ^ SyntaxError: invalid syntax *** Error compiling ./doc/rest2html.py ... File "./doc/rest2html.py", line 41 except ValueError, e: ^ SyntaxError: invalid syntax *** Error compiling ./doc/rest2latex.py ... File "./doc/rest2latex.py", line 44 except ValueError, e: ^ SyntaxError: invalid syntax *** Error compiling ./doc/s5/rst2s5.py ... File "./doc/s5/rst2s5.py", line 82 parsed = highlight(u'\n'.join(self.content), lexer, formatter) ^ SyntaxError: invalid syntax *** Error compiling ./ez_setup.py ... File "./ez_setup.py", line 106 except pkg_resources.VersionConflict, e: ^ SyntaxError: invalid syntax *** Error compiling ./src/local_doctest.py ... File "./src/local_doctest.py", line 372 raise TypeError, 'Expected a module: %r' % module ^ SyntaxError: invalid syntax *** Error compiling ./src/lxml/html/_diffcommand.py ... File "./src/lxml/html/_diffcommand.py", line 85 print "Not yet implemented" ^ SyntaxError: invalid syntax *** Error compiling ./src/lxml/html/tests/transform_feedparser_data.py ... File "./src/lxml/html/tests/transform_feedparser_data.py", line 91 print 'Bad data in %s:' % filename ^ SyntaxError: invalid syntax *** Error compiling ./src/lxml/tests/test_errors.py ... File "./src/lxml/tests/test_errors.py", line 1 # -*- coding: utf-8 -*- ^ SyntaxError: invalid character in identifier *** Error compiling ./tools/xpathgrep.py ... File "./tools/xpathgrep.py", line 5 except ImportError, e: ^ SyntaxError: invalid syntax -- Arfrever Frehtes Taifersar Arahesis

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[lxml-dev] Compile failure
by felix Nov. 23, 2010

Nov. 23, 2010

According to this: http://codespeak.net/lxml/build.html we should avoid installing Cython but using easy_install to build fails saying the cython generated file is missing I tried to build from source (svn checkout) and had the same issue Last Changed Author: scoder Last Changed Rev: 78186 Last Changed Date: 2010-10-21 13:48:54 -0400 (Thu, 21 Oct 2010) so I install cython anyway and try to compile the source, this also fails : Error converting Pyrex file to C: ------------------------------------------------------------ ... c_child = _findChildForwards(c_node, 0) while c_child is not NULL: if c_child.type == tree.XML_ELEMENT_NODE: for i in range(c_tag_count): if _tagMatchesExactly(c_child, c_ns_tags[2*i], c_ns_tags[2*i+1]): c_next = _findChildForwards(c_child, 0) or _nextElement(c_child) ^ ------------------------------------------------------------ /home/crucial/tmp/lxml/src/lxml/cleanup.pxi:246:64: Cannot assign type 'int' to 'xmlNode *' building 'lxml.etree' extension gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -I/usr/local/include -I/usr/local/include/libxml2 -I/usr/include/python2.6 -c src/lxml/lxml.etree.c -o build/temp.linux-x86_64-2.6/src/lxml/lxml.etree.o -w src/lxml/lxml.etree.c:1:2: error: #error Do not use this file, it is the result of a failed Cython compilation. *but then I succeeded with the old sudo easy_install lxml* because now I have Cython just FYI. so the advice on the build page says not to install Cython but that was the only way I got it to work. building from source in that checkout failed

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[lxml-dev] XSLT: Issues encountered when transforming docbook
by Jérôme Carretero Nov. 1, 2010

Nov. 1, 2010

Hi all, Using a python-based build tool, I decided to use lxml directly instead of calling xsltproc in order to transform docbook sources. The docbook sources contain olinks (links between documents). Everything works fine when using xsltproc. I tried the following : def xsltproc(xml_filename, xslt_filename, **kw): parser = etree.XMLParser() xml_doc = etree.parse(xml_filename, parser) print xml_doc.getroot().base xml_doc.xinclude() xslt_doc = etree.parse(xslt_filename) ac = etree.XSLTAccessControl(read_network=True, write_file=True, read_file=True, create_dir=True) transform = etree.XSLT(xslt_doc, access_control=ac) result_tree = transform(xml_doc, **kw) res = etree.tostring(result_tree, pretty_print=True, encoding="utf-8", xml_declaration=True) print "Transform\n", transform.error_log print "Parser\n", parser.error_log if not res: raise Exception("pouet") return res kw = { "olink.base.uri" : "doc.html", "collect.xref.targets" : "yes", "targets.filename" : "doc.html.db", "target.database.document" : "olinkdb-html.xml", } res = xsltproc("doc.xml", ".../xsl/xhtml/docbook.xsl", **kw) with open("pouet", "w") as f: f.write(res) This code fails silently (Exception("pouet") is raised). If I comment the line with remove collect.xref.targets, a document is correctly output. But the olinks are screwed. Somehow the xslt transformer is not able to read the olink information of other documents, by reading the pointers in olinkdb-html.xml. It seems that the silent failure is a bug, and I may be missing some stuff in order to convert the documents properly. More complete test cases available upon request. Thank you all, -- cJ

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