Mailman 3 June 2011 - 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-dev] confusing xpath performance characteristics
by jholg＠gmx.de 24 Aug '12

24 Aug '12

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] Codespeak shutting down: migration plans?
by Luciano Ramalho 23 Jul '11

23 Jul '11

Dear colleagues, As a long-time user of lxml I was shocked to read a message today from Holger Krekel about the end of Codespeak (see full text at the end of this). First we need to thank Holger for all these years of free service. Then we need to quickly plan and execute a migration to some other repository. I am willing to help, but I am no core developer of lxml, and in fact this is my first message ever to this mailing list, so I think we need someone better known to this community to lead the migration effort. lxml as a key piece of the Python ecosystem and for the benefit of its present and future users and the wider Python community we need to make sure it continues to be available, and to make sure as many references (pypi!) as possible point to the new canonical repository. Finally, a big thank you to Martijn, Philikon, Stefan and all the others who have built this great piece of software. Cheers, -- Luciano Ramalho programador repentista || stand-up programmer Twitter: @luciano ######################################### hi codespeak.net users, (sorry if you get mail twice, i wanted to make sure ...) after 8 years of operation codespeak.net services are bound to terminate, starting END OF FEBRUARY 2011 Background: one of the original codespeak purposes was to offer subversion (then in version 0.17) for the PyPy and other projects but today this is not too interesting given the pletora of VCS hosting solutions. Also, there aren't too many admins besides me, the hosting is costing money, PyPy's repository has moved to Bitbucket and i am re-shuffling my priorities preparing for my soon to emerge father-hood. After February 2011 i probably won't be able to help much with any transition issues or questions. The host will keep on running for a while but i give no guaruantees. Some remarks regarding termination wrt to the FEB 2011 deadline: * the subversion repo will turn read-only (and will eventually be switched off). * Shell accounts will be restricted to those people who need it *and* mail me about it. Some time later they will be gone as well. * Mailing lists will be terminated as well unless i get a mail asking me to postpone termination for a specific time. You can go to your respective mailman admin page and extract a list of members. If you mail me i can also provide a list of members. * Any remaining web docs/pages will probably continue to exist for a while but i also prefer them to be moved away by end Feb 2011. Note that the codespeak svn repository contains a lot of projects. For migration you have two options: do a flat import just of your project checkout directory into a new version system. This is super-simple, obviously. If you want to preserve history for your project please mail me and i either provide you a full dump or a filtered dump only containing your project. So long and I hope you all had a good time and enjoyed the services and also have a good transition now. see you in other places, holger krekel _______________________________________________ codespeak-ann(a)codespeak.net http://codespeak.net/mailman/listinfo/codespeak-ann

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Any plans for pypy support?
by F Wolff 16 Jul '11

16 Jul '11

I've been watching the development of pypy with great interest. Over all the pyhton projects I contribute to, there are many modules that already work fine with pypy, with a few that don't. Lxml is our favourite library for XML handling, and we mostly gave up on etree compatibility some time ago to benefit from the best APIs in lxml. So I'm curious to know if there are any plans to support lxml in pypy or any other ideas in this area that might be of interest. I don't have a burning need to run my software right now with pypy, but I'm interested in the possibility, as it seems quite mature and useful already. Friedel -- Recently on my blog: http://translate.org.za/blogs/friedel/en/content/virtaal-070-released

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Strange manifest issues with embedded python interpreter
by Rohan Dsa 29 Jun '11

29 Jun '11

Hello again, I am using the lxml binaries for Windows 7 via easy_install directions on the website. Standalone version When i import lxml, etree via python.exe, everything works ok. it seems the lxml was built against msvc90 runtime library (c Runtime libs). Embedded version I have been embedding the python interpreter in the past in a c++ application developed in VS2010. When I try to run this, it fails when it attempts to load the etree.pyd with the Err R6034. http://msdn.microsoft.com/en-us/library/ms235560%28v=VS.90%29.aspx I think it fails more exactly when trying to load the wrong run time msvc90. dll which is laying next to my exe. This is the manifest info embedded in the etree.pyd binary <assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0"> <trustInfo xmlns="urn:schemas-microsoft-com:asm.v3"> <security> <requestedPrivileges> <requestedExecutionLevel level="asInvoker" uiAccess="false"></requestedExecutionLevel> </requestedPrivileges> </security> </trustInfo> <dependency> </dependency> </assembly> On renaming this to dll and editing via studio so that there is no manifest resource in the binary but just padding, it starts to work in the embedded environment. Even though I have the solution, I still did not understand what the problem is in my case. Do you'll have a manifest policy? Also i noticed the usual pyd in the python distribution have no manifest info embedded in them. Also since I would prefer releasing only one set of c runtime redistributibles (not msvc90 for etree.pyd and msvc100 for the rest of my app), is it possible to get access to a vcproj/vcxproj so that i could generate my own pyds? Best Regards and many thanks for your Library, Rohan

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E-factory - ElementMaker - RSS and namespaces
by dev＠kihonkai.com 29 Jun '11

29 Jun '11

Hi, Short version of my question: The tutorial (http://lxml.de/tutorial.html#the-e-factory) shows how to create a basic xml document without a namespace and then an example with a namespace. But how do you apply the namespace to only on element? e.g. in the RSS sample below. More details: I recently found the lxml library and have found it very useful. So far I have been able to generate a standard RSS file. I used python like this: from lxml.builder import E from lxml import etree rss = ( E.rss( E.channel( E.title("Page Title"), E.link(""), E.description("Feed info"), ) ) ) tree = etree.ElementTree(rss) channel = rss[0] item = (E.item( E.title("Item-%03i" % (i)), E.link("http://example.com/%i" % (i)), E.description("this is a"), E.pubdate('Mon, %02i Jun 2011 11:00:00 +0100' % (day_num)), )) channel.append(item) I have just cut out a smaller part of a working script here. Eventually I will use other logic to generate the items. This example was just in a simple loop to create 3 items. Now that's all been going fine, but I wanted to open an existing RSS file and sort the items, I found that is not going to work with the pubdate as its in the RFC 822 format. So I started looking at the dublin core namespace. But I have not found a way to use the above method and add only the 'dc:' prefix to certain elements. The lxml tutorial (http://lxml.de/tutorial.html#the-e-factory) shows how to create a basic xml document without a namespace and then an example with a namespace. But how do you apply the namespace to only on element? e.g. in the RSS below. Mainly to add the date that is sortable. <rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/"> <channel> <title>Example feed</title> <link>http://example.feed.com</link> <description>Example with the dc field</description> <item> <title>Example item</title> <link>http://example.feed.com/1</link> <guid>http://example.feed.com/1</guid> <pubDate>Thu, 25 Feb 2010 21:56:24 GMT</pubDate> <dc:source>http://feed.com/</dc:source> <dc:date>2010-02-25T21:56:24+00:00</dc:date> </item> </channel> </rss> Thanks in advance. Steve

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