XSLT to remove all but one complex element - xslt

Question

I have a large XML (from Agile) that I need to pass into a system that cannot quickly read large XMLs. There is a repeating element that has a unique child element, I'd like to remove all of the others except the one I pass in with a parameter.
<AgileData xmlns="http://www.oracle.com/webfolder/technetwork/xml/plm/2013/09/">
<Parts uniqueId="10000:6049719:8336339">
<TitleBlock><Number>300901</Number></TitleBlock>
<PartType>Raw Material</PartType>
<LifecyclePhase>Production</LifecyclePhase>
<Description>Prod 1 Desc</Description>
<ProductLines><Value>123-Line</Value></ProductLines>
</Parts>
<Parts uniqueId="10000:6049719:8337000">
<TitleBlock><Number>300902</Number></TitleBlock>
<PartType>Raw Material</PartType>
<LifecyclePhase>Prototype</LifecyclePhase>
<Description>Prod 2 Desc</Description>
<ProductLines><Value>222-Line</Value></ProductLines>
</Parts>
<Parts uniqueId="10000:6049719:8337034">
<TitleBlock><Number>300908</Number></TitleBlock>
<PartType>Raw Material</PartType>
<LifecyclePhase>Prototype</LifecyclePhase>
<Description>Prod 3 Desc</Description>
<ProductLines><Value>123-Line</Value></ProductLines>
</Parts>
</AgileData>
Desired Output is the following when passing in the parameter Item
<AgileData xmlns="http://www.oracle.com/webfolder/technetwork/xml/plm/2013/09/">
<Parts uniqueId="10000:6049719:8337000">
<TitleBlock><Number>300902</Number></TitleBlock>
<PartType>Raw Material</PartType>
<LifecyclePhase>Prototype</LifecyclePhase>
<Description>Prod 2 Desc</Description>
<ProductLines><Value>222-Line</Value></ProductLines>
</Parts>
</AgileData>
This what I have so far, though it's not working.
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns="http://www.oracle.com/webfolder/technetwork/xml/plm/2013/09/">
<xsl:output omit-xml-declaration="no" indent="yes"/>
<xsl:param name="Item" select="300902" />
<xsl:template match="/AgileData">
<xsl:apply-templates select="//Parts"/>
</xsl:template>
<xsl:template match="//Parts/*[TitleBlock/Number='$Item']">
<xsl:copy-of select="."/>
</xsl:template>
</xsl:stylesheet>
After its working I'll change the parameter to just have a name and not a hardcoded value as it will get passed in from the engine. I can use XSLT 1.0 and 2.0.

Answer 1

Or simply:
XSLT 1.0
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:ns0="http://www.oracle.com/webfolder/technetwork/xml/plm/2013/09/">
<xsl:output method="xml" version="1.0" encoding="utf-8" indent="yes"/>
<xsl:param name="Item" select="300902" />
<xsl:template match="/ns0:AgileData">
<xsl:copy>
<xsl:copy-of select="ns0:Parts[ns0:TitleBlock/ns0:Number=$Item]"/>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
If you can use XSLT 2.0, it can be even simpler:
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xpath-default-namespace="http://www.oracle.com/webfolder/technetwork/xml/plm/2013/09/">
<xsl:output method="xml" version="1.0" encoding="utf-8" indent="yes"/>
<xsl:param name="Item" select="300902" />
<xsl:template match="/AgileData">
<xsl:copy>
<xsl:copy-of select="Parts[TitleBlock/Number=$Item]"/>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>

Answer 2

This XSLT 2.0 transformation:
<xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:x="http://www.oracle.com/webfolder/technetwork/xml/plm/2013/09/">
<xsl:output omit-xml-declaration="yes"/>
<xsl:param name="pItem" select="300902" />
<xsl:template match="node()|#*">
<xsl:copy>
<xsl:apply-templates select="node()|#*"/>
</xsl:copy>
</xsl:template>
<xsl:template match="x:Parts[x:TitleBlock/x:Number/number() ne $pItem]"/>
</xsl:stylesheet>
When applied on the provided XML document:
<AgileData xmlns="http://www.oracle.com/webfolder/technetwork/xml/plm/2013/09/">
<Parts uniqueId="10000:6049719:8336339">
<TitleBlock><Number>300901</Number></TitleBlock>
<PartType>Raw Material</PartType>
<LifecyclePhase>Production</LifecyclePhase>
<Description>Prod 1 Desc</Description>
<ProductLines><Value>123-Line</Value></ProductLines>
</Parts>
<Parts uniqueId="10000:6049719:8337000">
<TitleBlock><Number>300902</Number></TitleBlock>
<PartType>Raw Material</PartType>
<LifecyclePhase>Prototype</LifecyclePhase>
<Description>Prod 2 Desc</Description>
<ProductLines><Value>222-Line</Value></ProductLines>
</Parts>
<Parts uniqueId="10000:6049719:8337034">
<TitleBlock><Number>300908</Number></TitleBlock>
<PartType>Raw Material</PartType>
<LifecyclePhase>Prototype</LifecyclePhase>
<Description>Prod 3 Desc</Description>
<ProductLines><Value>123-Line</Value></ProductLines>
</Parts>
</AgileData>
produces the wanted, correct result:
<AgileData xmlns="http://www.oracle.com/webfolder/technetwork/xml/plm/2013/09/">
<Parts uniqueId="10000:6049719:8337000">
<TitleBlock><Number>300902</Number></TitleBlock>
<PartType>Raw Material</PartType>
<LifecyclePhase>Prototype</LifecyclePhase>
<Description>Prod 2 Desc</Description>
<ProductLines><Value>222-Line</Value></ProductLines>
</Parts>
</AgileData>
XSLT 1.0 solution:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:x="http://www.oracle.com/webfolder/technetwork/xml/plm/2013/09/">
<xsl:output omit-xml-declaration="yes"/>
<xsl:param name="pItem" select="300902" />
<xsl:template match="node()|#*" name="identity">
<xsl:copy>
<xsl:apply-templates select="node()|#*"/>
</xsl:copy>
</xsl:template>
<xsl:template match="x:Parts">
<xsl:if
test="x:TitleBlock/x:Number = $pItem"><xsl:call-template name="identity"/></xsl:if>
</xsl:template>
</xsl:stylesheet>
When this transformation is applied on the same XML document (above), the same correct / wanted result is produced.
Do note:
The use and overriding of the identity rule
The use of the same namespace as the default namespace in the XML document.
To learn more about the either of these important concepts, do search SO or the internet for "XSLT identity template / rule" and "XSLT processing a document in default namespace"
See also:
Dave Pawson's XSLT FAQ on Identity transformation
Dave Pawson's XSLT FAQ on Namespaces