XSLT merge multiple nodes under same parent - xslt

Question

Input XML is
<Operations>
<ID>10</ID>
<UserArea>
<AdditionalPhantomInformation>
<PhantomItem>
<ItemCode>41341288</ItemCode>
<SubComponent>40241289</SubComponent>
<Position>1</Position>
</PhantomItem>
</AdditionalPhantomInformation>
</UserArea>
<ConsumedItem>
<LineNumber>3</LineNumber>
<ParentItem>40241288</ParentItem>
</ConsumedItem>
<UserArea>
<AdditionalPhantomInformation>
<PhantomItem>
<ItemCode>41341288</ItemCode>
<SubComponent>40241302</SubComponent>
<Position>5</Position>
</PhantomItem>
</AdditionalPhantomInformation>
</UserArea>
</Operations>
And my expected output is
<Operations>
<ID>10</ID>
<UserArea>
<AdditionalPhantomInformation>
<PhantomItem>
<ItemCode>41341288</ItemCode>
<SubComponent>40241289</SubComponent>
<Position>1</Position>
</PhantomItem>
<PhantomItem>
<ItemCode>41341288</ItemCode>
<SubComponent>40241302</SubComponent>
<Position>5</Position>
</PhantomItem>
</AdditionalPhantomInformation>
</UserArea>
<ConsumedItem>
<LineNumber>3</LineNumber>
<ParentItem>40241288</ParentItem>
</ConsumedItem>
</Operations>
I have searched various sources and tried, but i'm unable to get the xslt right. I don't know how to use xsl:for-each-group. Please help. I'm using XSLT 2.0.

Answer 1

You don't necessarily need xsl:for-each-group here, as all you are doing is combining specific nodes into one.
Start off with the identity template...
<xsl:template match="#*|node()">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
</xsl:copy>
</xsl:template>
Or, if you could use XSLT 3.0....
<xsl:mode on-no-match="shallow-copy"/>
Then have a template matching the first UserArea which does the combining...
<xsl:template match="UserArea[1]">
<xsl:copy>
<xsl:apply-templates select="node()|following-sibling::UserArea/node()" />
</xsl:copy>
</xsl:template>
You would then just need another template to ensure the other UserArea elements are not output in their original position.
<xsl:template match="UserArea" />
Try this XSLT
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0">
<xsl:output method="xml" indent="yes" />
<xsl:strip-space elements="*" />
<xsl:template match="#*|node()">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
</xsl:copy>
</xsl:template>
<xsl:template match="UserArea[1]">
<xsl:copy>
<xsl:apply-templates select="node()|following-sibling::UserArea/node()" />
</xsl:copy>
</xsl:template>
<xsl:template match="UserArea" />
</xsl:stylesheet>
Note, if you did want to use xsl:for-each-group you would do it this way
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0">
<xsl:output method="xml" indent="yes" />
<xsl:strip-space elements="*" />
<xsl:template match="#*|node()">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
</xsl:copy>
</xsl:template>
<xsl:template match="Operations">
<xsl:copy>
<xsl:for-each-group select="*" group-by="name()">
<xsl:choose>
<xsl:when test="current-grouping-key() = 'UserArea'">
<xsl:copy>
<xsl:apply-templates select="current-group()/node()" />
</xsl:copy>
</xsl:when>
<xsl:otherwise>
<xsl:apply-templates select="current-group()" />
</xsl:otherwise>
</xsl:choose>
</xsl:for-each-group>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
This has the advantage of being easily extended if you had nodes other than UserArea you wished to combine.