How can I replace XML namespace prefixes with inline xmlns declarations?

Question

I have two XML objects that I believe describe the same entity, one uses namespace prefixes, and one uses inline namespace declarations. I want to diff them, but the different ways of representing the namespace make that all but impossible.

How can I take the first xml snippet below and change it to match the second snippet?

<!--I want to take data that looks like this-->
<Foo xmlns:e="http://schemas.cch.com/FooBar/MDS/2007/12/04/Foo">
  <e:Description></e:Description>
  <e:Name i:nil="true"></e:Name>
  <e:DisplaySeqNo>0</e:DisplaySeqNo>
</Foo>

<!--I want to make that data that looks like this-->
<Foo>
  <Description xmlns="http://schemas.cch.com/FooBar/MDS/2007/12/04/Foo"></Description>
  <Name i:nil="true" xmlns="http://schemas.cch.com/FooBar/MDS/2007/12/04/Foo"></Name>
  <DisplaySeqNo xmlns="http://schemas.cch.com/FooBar/MDS/2007/12/04/Foo">0</DisplaySeqNo>
</Foo>

The requirement to diff them is part of a manual debugging process process, so I'd be happy with a web tool, script, or whatever. I don't plan on doing this regularly but am ripping my hair out trying to figure out how xml sample A is different than xml sample B.

Preferred languages or technologies for a non-XSLT solution? — , Feb 06 '20 at 21:58
@Amy I've never used XSLT, so I don't know if I'm ok with it or not, but if a snippet can get me from A to B I'd be more than happy to use it. — Sidney, Feb 06 '20 at 21:59
My current thinking is you could start with and adapt [this code](https://stackoverflow.com/questions/5268182/how-to-remove-namespaces-from-xml-using-xslt), except instead of removing, you replace. I think `localname()` would need to become `name()`. *I think*. My knowledge of XSLT is rather limited. — , Feb 06 '20 at 22:02

score 2 · Accepted Answer · answered Feb 06 '20 at 22:09

You can use the following XSLT-1.0 stylesheet. It's a combination of the Identity template (which copies all nodes) with two templates handling the replacement situation:

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:e="http://schemas.cch.com/FooBar/MDS/2007/12/04/Foo">
    <xsl:output method="xml" indent="yes"/>

    <!-- Identity template -->
    <xsl:template match="@*|node()">
        <xsl:copy>
            <xsl:apply-templates select="@*|node()"/>
        </xsl:copy>
    </xsl:template>

    <xsl:template match="Foo">
      <xsl:element name="{local-name()}" namespace="">
        <xsl:apply-templates select="node()|@*" />
      </xsl:element>
    </xsl:template>

    <xsl:template match="e:*">
      <xsl:element name="{local-name()}" namespace="http://schemas.cch.com/FooBar/MDS/2007/12/04/Foo">
        <xsl:apply-templates select="node()|@*" />
      </xsl:element>
    </xsl:template>    

</xsl:stylesheet>

Its output is:

<Foo>
  <Description xmlns="http://schemas.cch.com/FooBar/MDS/2007/12/04/Foo"/>
  <Name xmlns="http://schemas.cch.com/FooBar/MDS/2007/12/04/Foo" i:nil="true"/>
  <DisplaySeqNo xmlns="http://schemas.cch.com/FooBar/MDS/2007/12/04/Foo">0</DisplaySeqNo>
</Foo>

It also produces an error for the XML file, because the i namespace is not defined in it. It also copies the comment from the input XML, but I guess that was just a comment for illustration and can therefore be ignored.

If you're using some kind of Linux, you can easily pass this template to xsltproc.

Just an FYI, in windows this can be done by having an xml file, adding a xslt file to the xml file's stylesheet property, then choosing to start xslt (with or without debugging) from visual studio. (Also, thank you!) — Sidney, Feb 06 '20 at 22:17

How can I replace XML namespace prefixes with inline xmlns declarations?

1 Answers1