Mailman 3 May 2019 - 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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Accessing variables from within an XSL file
by Adrian Bool 05 Apr '21

05 Apr '21

Hi, I'm trying to extract from data from XSL files on an IBM DataPower system. I can't change the XSLT files - and therefore need to work around their current structure to get the info I need. I'm doing this from within Python 3.7 using etree.__version__ 4.3.3. Here are my imports, a dummy XML object and a cutdown version of the XSL file from the IBM system: from lxml import etree from textwrap import dedent xml = etree.XML("""<root></root>""") xsl = etree.XML(dedent( """<?xml version="1.0"?> <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:dp="http://www.datapower.com/extensions" extension-element-prefixes="dp"> <xsl:template match="node()|@*"> <xsl:copy> <xsl:apply-templates select="node()|@*"/> </xsl:copy> <xsl:variable name="destination_url"> <xsl:value-of select="'https://my.domain.example.com/'" /> </xsl:variable>  <dp:set-variable name="'var://context/mpgw/Destination'" value="$destination_url" /> </xsl:template> </xsl:stylesheet> """)) My goal is to use lxml to process this file and extract the contents of the DataPower variable 'var://context/mpgw/Destination' - i.e. the contents of the xsl:variable $destination_url - in the above case ' https://my.domain.example.com/'. I've created an XSLT extension for the "dp:set-variable" element to try to capture this information: class MyExtElement(etree.XSLTExtension): def execute(self, context, self_node, input_node, output_parent): if self_node.tag == '{ http://www.datapower.com/extensions}set-variable': print(f"Setting variable of name {self_node.get('name')} to value {self_node.get('value')}") extensions = { ('http://www.datapower.com/extensions', 'set-variable') : MyExtElement() } result = etree.XSLT(xsl, extensions=extensions)(xml) print(f"Result: {result}") When this is being called; instead of the value of destination_url I'm getting the static "$destination_url" string instead - with the output of the above script being: Setting variable of name 'var://context/mpgw/Destination' to value $destination_url Result: <?xml version="1.0"?> <root/> I am rather suprised that the $destination_url xsl:variable was not being evaluated - does anyone know why this is the case? Given the above, I've been trying to find a way to access the $destination_url xsl:variable from within my XSLTExtension - but unfortunately with no luck. Some things I've tried: * Calling self.process_children(context) within the extension - this just results in an empty list. * I've used dir() to look through the context, self_node and input_node args to try to find somewhere the variables may be accessible but with no luck. * I've used deepcopy to clone self_node to get an xpath function on this argument and made some attempts at using xpath to access the xsl variable - all unsuccessful: node = deepcopy(self_node) node.xpath("""<xsl:value-of select="$destination_url">""") *** lxml.etree.XPathEvalError: Invalid expression node.xpath("""$destination_url""") *** lxml.etree.XPathEvalError: Undefined variable node.xpath("""xsl:$destination_url""") *** lxml.etree.XPathEvalError: Invalid expression node.xpath("""xsl:$destination_url""", namespaces={'xsl':'http://www.w3.org/1999/XSL/Transform'}) *** lxml.etree.XPathEvalError: Invalid expressio node.xpath("""$destination_url""", namespaces={'xsl':'http://www.w3.org/1999/XSL/Transform'}) *** lxml.etree.XPathEvalError: Undefined variable node.xpath("""/xsl:$destination_url""", namespaces={'xsl':'http://www.w3.org/1999/XSL/Transform'}) *** lxml.etree.XPathEvalError: Invalid expression node.xpath("""<xsl:value-of select="$destination_url">""", namespaces={'xsl':'http://www.w3.org/1999/XSL/Transform'}) *** lxml.etree.XPathEvalError: Invalid expression I'm lost now! Any suggestions greatly appreciated! Cheers, aid

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Canonicalization support
by João M. S. Silva 24 May '19

24 May '19

Hi, Is it true that lxml (3.2.1) does not support http://www.w3.org/TR/xml-c14n11? If so, can we simply modify the source code and add this c14n method to the list? Would it be safe? Thanks. João M. S. Silva

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Probable bug with nested lists in v4.3.3
by Alex Krupp 19 May '19

19 May '19

For nested lists in HTML, the nested list is supposed to be within an <li> element rather than as a child of the <ol> or <ul>. Given this first example of a slightly non-conformant HTML snippet produced by Gmail: >>> from lxml import etree >>> html = etree.HTML('<ol><li>1</li><ol><li>2</li></ol></ol>') >>> etree.tostring(html) b'<html><body><ol><li>1</li></ol><ol><li>2</li></ol></ol></body></html>' The above code snippet works the way I would expect, in that even though the input isn't entirely valid html, the nested ordered list is still within the outer ordered list. However, if we look at this code snippet below, which is identical except for that now the nested list is an unordered list: >>> from lxml import etree >>> html = etree.HTML('<ol><li>1</li><ul><li>*</li></ul></ol>') >>> etree.tostring(html) b'<html><body><ol><li>1</li></ol><ul><li>*</li></ul></body></html>' Suddenly the unordered list is no longer nested inside the ordered list. Unless there is something I don't know about in the HTML spec prohibiting nested lists of mixed types, this seems both inconsistent with the first example and broken in general. I would expect instead for lxml to produce one of the following two trees: <ol><li>1</li><ul><li>*</li></ul></ol> <ol><li>1</li><li><ul><li>*</li></ul></li></ol> Either would be fine, but what currently gets produced seems pretty suboptimal because it substantially changes the meaning of the text. Alex -- Alex Krupp Cell: (607) 351 2671 Read my Email: www.fwdeveryone.com/u/alex3917 Subscribe to my blog: http://alexkrupp.typepad.com/ My homepage: www.alexkrupp.com

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recursively expand all includes and exports
by Robert Lario 08 May '19

08 May '19

Is there a means to recursively expand all includes and exports? I would like to use xpath that will walk all imports and includes. Is this possible? Thanks

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[lxml-dev] etree.cleanup_namespaces() removes namespaces that are used in ns-prefixed attribute values
by Holger Joukl 02 May '19

02 May '19

Hi, would that be a bug or is it just not supported/sanely supportable? >>> root = etree.fromstring('<root xmlns:xsd=" http://www.w3.org/2001/XMLSchema" xmlns:xsi=" http://www.w3.org/2001/XMLSchema-instance"><x xsi:type="xsd:integer">42</x></root>') >>> print etree.tostring(root, pretty_print=True) <root xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi=" http://www.w3.org/2001/XMLSchema-instance"> <x xsi:type="xsd:integer">42</x> </root> >>> etree.cleanup_namespaces(root) >>> print etree.tostring(root, pretty_print=True) <root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <x xsi:type="xsd:integer">42</x> </root> Note how the XML Schema namespace as used in xsd:integer has been removed. >>> print etree.__version__ # oldschool ;-) 3.7.2 Holger Landesbank Baden-Wuerttemberg Anstalt des oeffentlichen Rechts Hauptsitze: Stuttgart, Karlsruhe, Mannheim, Mainz HRA 12704 Amtsgericht Stuttgart HRA 4356, HRA 104 440 Amtsgericht Mannheim HRA 40687 Amtsgericht Mainz Die LBBW verarbeitet gemaess Erfordernissen der DSGVO Ihre personenbezogenen Daten. Informationen finden Sie unter https://www.lbbw.de/datenschutz.

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