Change namespaces using XSLT - xslt

Question

I'm writing a wrapper layer over an existing out of the box service. For this, I need to convert the namespaces of the xml that is returned by the service to my namespaces
The xml has different namespaces for different tags, and I need to map them to another set of namespaces
In other words, the prefix
ns1 to be modified to myns1
ns2 to myns2, and so on...
Here is how my XML looks like
<ns1:Response>
<ns2:task>..</ns2:task>
<ns2:address>..</ns2:address>
<ns2:pin>..</ns2:pin>
<ns3:address>
<ns4:add1>..</ns4:add1>
<ns4:add2>..</ns4:add2>
<ns4:add3>
<ns5:asdf>..</ns5:asdf>
<ns5:qwe>..</ns5:qwe>
</ns4:add3>
<ns4:add4>..</ns4:add4>
</ns3:address>
<ns2:query>..</ns2:query>
</ns1:Response>
And I want to change this to
<myns1:Response>
<myns2:task>..</myns2:task>
<myns2:address>..</myns2:address>
<myns2:pin>..</myns2:pin>
<myns3:address>
<myns4:add1>..</myns4:add1>
<myns4:add2>..</myns4:add2>
<myns4:add3>
<myns5:asdf>..</myns5:asdf>
<myns5:qwe>..</myns5:qwe>
</myns4:add3>
<myns4:add4>..</myns4:add4>
</myns3:address>
<myns2:query>..</myns2:query>
</myns1:Response>
Basically, just the namespace prefixes change from one set to another.
Can you please suggest me how to do this in xslt?
I've tried using apply-templates, but i'm not able to figure out a solution
Regards
Ravi

Answer 1

The following stylesheet worked!
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:myns1="http://www.w3.org/TR/html4/1"
xmlns:myns2="http://www.w3.org/TR/html4/2"
xmlns:myns3="http://www.w3.org/TR/html4/3"
xmlns:myns4="http://www.w3.org/TR/html4/4"
xmlns:myns5="http://www.w3schools.com/furniture"
xmlns:ns1="http://www.w3.org/TR/html4/1"
xmlns:ns2="http://www.w3.org/TR/html4/2"
xmlns:ns3="http://www.w3.org/TR/html4/3"
xmlns:ns4="http://www.w3.org/TR/html4/4"
xmlns:ns5="http://www.w3schools.com/furniture">
<xsl:template match="*">
<myns1:taskListResponse>
<xsl:apply-templates/>
</myns1:taskListResponse>
</xsl:template>
<xsl:template match="ns2:*">
<xsl:element name="myns2:{local-name()}">
<xsl:apply-templates/>
</xsl:element>
</xsl:template>
<xsl:template match="ns3:*">
<xsl:element name="myns3:{local-name()}">
<xsl:apply-templates/>
</xsl:element>
</xsl:template>
<xsl:template match="ns4:*">
<xsl:element name="myns4:{local-name()}">
<xsl:apply-templates/>
</xsl:element>
</xsl:template>
<xsl:template match="ns5:*">
<xsl:element name="myns5:{local-name()}">
<xsl:apply-templates/>
</xsl:element>
</xsl:template>
</xsl:stylesheet>
But seriously, I'm not able to understand how this works.
The snippet
<xsl:template match="ns2:*">
<xsl:element name="myns2:{local-name()}">
<xsl:value-of select="." />
</xsl:element>
</xsl:template>
means match all elements that start with ns2: and replace with myns2:
But when I used the same logic for all, it gave only the first 2 level elements
Ex :
Stylesheet
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:myns1="http://www.w3.org/TR/html4/1"
xmlns:myns2="http://www.w3.org/TR/html4/2"
xmlns:myns3="http://www.w3.org/TR/html4/3"
xmlns:myns4="http://www.w3.org/TR/html4/4"
xmlns:myns5="http://www.w3schools.com/furniture"
xmlns:ns1="http://www.w3.org/TR/html4/1"
xmlns:ns2="http://www.w3.org/TR/html4/2"
xmlns:ns3="http://www.w3.org/TR/html4/3"
xmlns:ns4="http://www.w3.org/TR/html4/4"
xmlns:ns5="http://www.w3schools.com/furniture">
<xsl:template match="/">
<myns1:taskListResponse>
<xsl:apply-templates/>
</myns1:taskListResponse>
</xsl:template>
<xsl:template match="ns2:*">
<xsl:element name="myns2:{local-name()}">
<xsl:value-of select="." />
</xsl:element>
</xsl:template>
<xsl:template match="ns3:*">
<xsl:element name="myns3:{local-name()}">
<xsl:value-of select="." />
</xsl:element>
</xsl:template>
<xsl:template match="ns4:*">
<xsl:element name="myns4:{local-name()}">
<xsl:value-of select="." />
</xsl:element>
</xsl:template>
<xsl:template match="ns5:*">
<xsl:element name="myns5:{local-name()}">
<xsl:value-of select="." />
</xsl:element>
</xsl:template>
</xsl:stylesheet>
returned
<?xml version="1.0" encoding="UTF-8"?><myns1:taskListResponse xmlns:ns2="http://www.w3.org/TR/html4/2" xmlns:ns3="http://www.w3.org/TR/html4/3" xmlns:ns4="http://www.w3.org/TR/html4/4" xmlns:ns5="http://www.w3schools.com/furniture" xmlns:myns1="http://www.w3.org/TR/html4/1" xmlns:myns2="http://www.w3.org/TR/html4/2" xmlns:myns3="http://www.w3.org/TR/html4/3" xmlns:myns4="http://www.w3.org/TR/html4/4" xmlns:myns5="http://www.w3schools.com/furniture" xmlns:ns1="http://www.w3.org/TR/html4/1">
<myns2:task>..</myns2:task>
<myns2:address>..</myns2:address>
<myns2:pin>..</myns2:pin>
<myns3:address>
..
..
..
..
..
</myns3:address>
<myns2:query>..</myns2:query>
</myns1:taskListResponse>
Here, you can see that ns4 & ns5 elements are completely missed. Where for the same template, instead of <xsl:value-of select="." />, If i use <xsl:apply-templates/>, it worked, meaning replaced all the level nodes. I seriously dont understand this as the match I used is * in the template.
Appreciate your response.
Regards
Ravi