Mailman 3 September 2020 - 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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Canonicalisation with unprefixed namespace bug
by Jamie Norrish 30 Sep '20

30 Sep '20

Hi, I just ran into a bug that is reported at https://bugs.launchpad.net/lxml/+bug/1869455 I am getting the same error using lxml 4.5.2 (the reporter was using version 4.5.0). At the moment I can easily work around it by specifying a not-None prefix in my namespaces map. But I'm not sure what the best way to set a prefix is when just loading a document and then serialising it using the c14n method. Jamie

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A strip_tags question
by Martin Mueller 15 Sep '20

15 Sep '20

I have texts that are linguistically and every token is wrapped in a <w> or <pc> element, like so: <l xml:id="c0abe-e140"> <w lemma="and" pos="cc" xml:id="c0abe-001-a-0670">and</w> <w lemma="therein" pos="av" xml:id="c0abe-001-a-0680">therein</w> <w lemma="take" pos="vvb" xml:id="c0abe-001-a-0690">take</w> <w lemma="delight" pos="n1" xml:id="c0abe-001-a-0700">delight</w> <pc xml:id="c0abe-001-a-0710">:</pc> </l> I'd like to strip the annotation and generate a plain file in which the <w> and <pc> elements are replaced by just their content. Some years ago I used the strip_tags method, and I remember it working. By this I mean that the words in a line of text appeared with a space between words. But when I use it now, it does strip the tags but the text appears verticalized, with one token on each line. I've tried various methods of getting rid of the line break, but none of them work. For instance, I used this bit of code to replace the linebreak with nothing: for element in tree.iter('*'): plaintext = element.text if plaintext is not None: plaintext = plaintext.replace('\n', '') This does something: if I print out each element, the line breaks go away. But if I then print out the whole file, using print(etree.tostring(tree, encoding = 'unicode', pretty_print=True) the result is a verticalized text. Which means that the deletion of the line breaks at a later stage, but I don’t know how to do that. I'll be grateful for advice Martin Mueller Professor English and Classics Northwestern University

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Using iterparse with a parser
by Ryan Gentner 04 Sep '20

04 Sep '20

Hello. I am trying to use iterparse() in lieu of parse(). According to the documentation, parse() can employ a parser, whereas iterparse() leaves no option for this. I have xml files using utf-8 characters and latin1 encoded characters. How can I accomplish parsing using both uft-8 and latin1 encodings using iterparse()? Any help on this would be greatly appreciated. Thank you. -Ryan -- -- This message is intended only for the use of the individual(s) or entity to which it is addressed and may contain information that is privileged, confidential, and/or proprietary to Apkudo. If the reader of this message is not the intended recipient, you are hereby notified that any dissemination, distribution, forwarding or copying of this communication is prohibited without the express permission of the sender. If you have received this communication in error, please notify the sender immediately and delete the original message.

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