adding segment to xml within the same xpath using xslt - xslt

Question

I need to group some of the fields into a segment when the segment does not appear.
I am able to add the segment by checking if the segment already exists.
XML
<ns1:MT_SalesOrder xmlns:ns1="urn:salesorder">
<Reason/>
<OrderId/>
<Invoice>
<CreatedTimestamp>2019-07-24T14:37:29.573</CreatedTimestamp>
<PublishCount>1</PublishCount>
<Process/>
<FailedAmount/>
<InvoiceLine>
<Address/>
<Total>-270.0</Total>
</InvoiceLine>
</Invoice>
<Info/>
<Comments/>
<Status/>
<Taxes/>
<Due>0.0</Due>
<OrderTotal>5.0</OrderTotal>
<messageKey>122345</messageKey>
<message>99999</message>
<errors>11111</errors>
<exceptions>222222</exceptions>
</ns1:MT_SalesOrder>
XSLT
<?xml version="1.0" encoding="UTF-8"?>
<ns0:stylesheet version="1.0" xmlns:ns0="http://www.w3.org/1999/XSL/Transform" xmlns:ns1="urn:salesorder">
<ns0:output omit-xml-declaration="yes" indent="yes"/>
<ns0:strip-space elements="*"/>
<ns0:template match="node()|#*">
<ns0:copy>
<ns0:apply-templates select="node()|#*"/>
</ns0:copy>
</ns0:template>
<ns0:template match="/ns1:MT_SalesOrder[not(data)]">
<ns0:copy>
<ns0:apply-templates select="#*"/>
<data>
<ns0:apply-templates select="node()"/>
</data>
</ns0:copy>
</ns0:template>
</ns0:stylesheet>
I am expecting the below structure, data to be added before messageKey Field.
<ns1:MT_SalesOrder xmlns:ns1="urn:salesorder">
<data> <---------------------------------------------
<Reason/>
<OrderId/>
<Invoice>
<CreatedTimestamp>2019-07-24T14:37:29.573</CreatedTimestamp>
<PublishCount>1</PublishCount>
<Process/>
<FailedAmount/>
<InvoiceLine>
<Address/>
<Total>-270.0</Total>
</InvoiceLine>
</Invoice>
<Info/>
<Comments/>
<Status/>
<Taxes/>
<Due>0.0</Due>
<OrderTotal>5.0</OrderTotal>
</data> <-------------------------------------------------
<messageKey>122345</messageKey>
<message>99999</message>
<errors>11111</errors>
<exceptions>222222</exceptions>
</ns1:MT_SalesOrder>
But I am getting the data segment added to the whole XML.
<ns1:MT_SalesOrder xmlns:ns1="urn:salesorder">
<data>
<Reason/>
<OrderId/>
<Invoice>
<CreatedTimestamp>2019-07-24T14:37:29.573</CreatedTimestamp>
<PublishCount>1</PublishCount>
<Process/>
<FailedAmount/>
<InvoiceLine>
<Address/>
<Total>-270.0</Total>
</InvoiceLine>
</Invoice>
<Info/>
<Comments/>
<Status/>
<Taxes/>
<Due>0.0</Due>
<OrderTotal>5.0</OrderTotal>
<messageKey>122345</messageKey>
<message>99999</message>
<errors>11111</errors>
<exceptions>222222</exceptions>
</data>
</ns1:MT_SalesOrder>
I am not able to copy the part of the XML and group them, the field messageKey is the identifier to split the XML and add in data segment. Any leads will be helpful. Thank you!

Answer 1

If you know in advance the names of all elements in the two groups, then the best way is to list them explicitly:
XSLT 1.0
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:ns1="urn:salesorder">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<xsl:strip-space elements="*"/>
<xsl:template match="ns1:MT_SalesOrder">
<xsl:copy>
<data>
<xsl:copy-of select="Reason | OrderId | Invoice | Info | Comments | Status | Taxes | Due | OrderTotal"/>
</data>
<xsl:copy-of select="messageKey | message | errors | exceptions"/>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
Otherwise you can use messageKey as the "split point":
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:ns1="urn:salesorder">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<xsl:strip-space elements="*"/>
<xsl:template match="ns1:MT_SalesOrder">
<xsl:copy>
<data>
<xsl:copy-of select="messageKey/preceding-sibling::*"/>
</data>
<xsl:copy-of select="messageKey | messageKey/following-sibling::*"/>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>