How to add SOAP Headers to soap message- XSLT - xslt

Question

I'm getting the SOAP request with empty Headers. I want to add custom headers to the incoming request and copy the soap body as is to the response.How to add xml tags in the Headers ?
Below is the incoming request:
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/">
<soapenv:Header/>
<soapenv:Body>
<input>
<numb>15171</numb>
</input>
</soapenv:Body>
</soapenv:Envelope>
Expected Output:
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/">
<soapenv:Header>
<Username xmlns="http://blah.com">username</Username>
<Password xmlns="http://blah.com">password</Password>
</soapenv:Header>
<soapenv:Body>
<input>
<numb>15171</numb>
</input>
</soapenv:Body>
</soapenv:Envelope>
Here is my XSLT which I tried:
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:soapenv="http://soap/envelope/"
version="1.0">
<xsl:output omit-xml-declaration="yes" indent="yes"/>
<xsl:template match="#*|node()">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
</xsl:copy>
</xsl:template>
<xsl:template match="soapenv:Header">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
<soapenv:Header>
<Username xmlns="http://blah.com">username</Username>
<Password xmlns="http://blah.com">password</Password>
</soapenv:Header>
</xsl:copy>
</xsl:template>
<xsl:template match="soapenv:Header"/>
</xsl:stylesheet>

Answer 1

Here's how you could do it.
Note that your 'soapenv' namespace in your XSLT was not matching what is defined in your input XML.
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"
version="1.0">
<xsl:output omit-xml-declaration="yes" indent="yes"/>
<xsl:template match="#*|node()">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
</xsl:copy>
</xsl:template>
<xsl:template match="soapenv:Header">
<xsl:copy>
<Username xmlns="http://blah.com">username</Username>
<Password xmlns="http://blah.com">password</Password>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
See it working here: https://xsltfiddle.liberty-development.net/6q1SDkU