XSLT get parent in match lxml python

Question

i have this XML:

<AAA>
    <BBB>
        <CCC>
            <DDD/>
        </CCC>
        <CCC>
            <EEE/>
        </CCC>
    </BBB>
    <BBB>
        <CCC>
            <EEE/>
        </CCC>
        <CCC>
            <DDD/>
        </CCC>
    </BBB>
    <BBB>
        <CCC>
            <EEE/>
        </CCC>
        <CCC>
            <EEE/>
        </CCC>
    </BBB>
    <BBB>
        <CCC>
            <DDD/>
        </CCC>
        <CCC>
            <EEE/>
        </CCC>
    </BBB>
</AAA>

And i want this result using a XSLT file:

<AAA>
   <XXX case="1" />
   <XXX case="2" />
   <XXX case="3" />
   <XXX case="1" />
</AAA>

Case 1: CCC[1] has DDD & CCC[2] has EEE
Case 2: CCC[1] has EEE & CCC[2] has DDD
Case 3: CCC[1] has EEE & CCC[2] has EEE

CCC always has only one item

I use the lxml Library in Python. I already got a XPath that matches case="1" in Notepad++:

//BBB/CCC[1]/DDD/../../CCC[2]/EEE

But if i try to use

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
<xsl:output indent="yes"/>

    <xsl:template match="BBB/CCC[1]/DDD/../../CCC[2]/EEE">
      <XXX case="1" />
    </xsl:template>

    <xsl:template match="node()|@*">
      <xsl:copy>
        <xsl:apply-templates select="node()|@*"/>
      </xsl:copy>
    </xsl:template>

</xsl:stylesheet>

I get this Error:

Traceback (most recent call last):
  File "C:/.../xsltest.py", line 11, in <module>
    transform_01 = etree.XSLT(xslt_01)
  File "xslt.pxi", line 412, in lxml.etree.XSLT.__init__ (src\lxml\lxml.etree.c:152223)
lxml.etree.XSLTParseError: Cannot parse stylesheet

If i only use BBB/CCC[1]/DDD the match works but it does not with the "..". How can i get the parent? Or is there another solution to my problem?

Waldi

With what logic are you relating your input to your output? What are case 1, 2, 3, and 1? Can you please explain. — Lingamurthy CS, Nov 26 '14 at 09:48
My bad, I don't understand it, still.. Can you try explaining it using sentences.. BTW, your template match, `BBB/CCC[1]/DDD/../../CCC[2]/EEE` is wrong, the axis in match pattern can have child axis or attribute axis.. you should try `BBB/CCC[2]/EEE` instead — Lingamurthy CS, Nov 26 '14 at 09:59
@LingamurthyCS if the 1. CCC element in a BBB has a DDD and the 2. CCC element has a EEE element -> case 1. if the 1. CCC element of a BBB element has a EEE and the 2. CCC element has a DDD -> case 2. if both CCC have a EEE element -> case 3. — W4ldi, Nov 26 '14 at 10:07
Please add the transform.error_log details when quoting Exceptions in \lxml\xslt.pxi. [errors-and-messages](https://lxml.de/xpathxslt.html#errors-and-messages) — dank8, Feb 20 '23 at 14:12

score 0 · Accepted Answer · answered Nov 26 '14 at 10:13

Use this XSLT:

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
<xsl:output indent="yes"/>
<xsl:template match="BBB">
    <xsl:choose>
        <xsl:when test="CCC[1]/DDD and CCC[2]/EEE">
            <XXX case="1"/>
        </xsl:when>
        <xsl:when test="CCC[1]/EEE and CCC[2]/DDD">
            <XXX case="2"/>
        </xsl:when>
        <xsl:when test="CCC[1]/EEE and CCC[2]/EEE">
            <XXX case="3"/>
        </xsl:when>
    </xsl:choose>
</xsl:template>
<xsl:template match="node()|@*">
    <xsl:copy>
        <xsl:apply-templates select="node()|@*"/>
    </xsl:copy>
</xsl:template>
</xsl:stylesheet>

XSLT get parent in match lxml python

1 Answers1