XSLT Processing two input files into one output file

Question

I'm trying to process to xml files (docbook documents). There are repeating structures in the document that I would extract from both documents, parameterize, and store in a separate document.

To get it simplified, here is an example:

file1.xml:

<?xml version="1.0" encoding="UTF-8"?>
<input>
    <structure>foo</structure>
    <structure>bar</structure>
    <structure>baz</structure>
</input>

file2.xml:

<?xml version="1.0" encoding="UTF-8"?>
<input>
    <structure>abc</structure>
    <structure>xyz</structure>
    <structure>123</structure>
</input>

And this is the preferred output, I would like to generate. output.xml:

<?xml version="1.0" encoding="UTF-8"?>
<output>
    <structure origin="doc1">foo</structure>
    <structure origin="doc1">bar</structure>
    <structure origin="doc1">baz</structure>
    <structure origin="doc2">abc</structure>
    <structure origin="doc2">xyz</structure>
    <structure origin="doc2">123</structure>
</output>

Now I don't know how to convert two or more documents (URI can be hard coded) and one additional parameter (doc1, doc2 - these can also be hard coded) in XSLT.

I would be very grateful for any hints.

Mads Hansen · Accepted Answer · 2022-01-11 17:16:59Z

2

Whether you transform file1.xml and only read file2.xml with fn:doc(), or set both parameters and read both is a matter of choice, but the concept applies either way. Once you have both docs loaded, you can XPath to the /input/structure and then apply-templates.

With XSLT 2.0, you can obtain the base-uri() and parse that for the filename to use in the @origin:

<xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
    xmlns:fn="http://www.w3.org/2005/xpath-functions" 
    exclude-result-prefixes="fn">
    <xsl:output indent="yes" />
    
    <xsl:param name="file1" select="'file1.xml'" />
    <xsl:param name="file2" select="'file2.xml'" />
    
    <xsl:template match="/">
        <output>
            <xsl:apply-templates select="(fn:doc($file1) | fn:doc($file2))/input/structure"/>
        </output>
    </xsl:template>
    
    <xsl:template match="structure">
        <xsl:copy>
          <xsl:attribute name="origin" select="concat('doc', replace(base-uri(), '.*(\d+).xml', '$1'))"/>
            <xsl:apply-templates select="@*|node()"/>
        </xsl:copy>
    </xsl:template>
    
</xsl:stylesheet>

If you need XSLT 1.0, you could send the filename as a param:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
    xmlns:fn="http://www.w3.org/2005/xpath-functions" 
    exclude-result-prefixes="fn">
    <xsl:output indent="yes" />
    
    <xsl:param name="file1" select="'file1.xml'" />
    <xsl:param name="file2" select="'file2.xml'" />
    
    <xsl:template match="/">
        <output>
            <xsl:call-template name="load-file">
                <xsl:with-param name="file" select="$file1"/>
            </xsl:call-template>
            <xsl:call-template name="load-file">
                <xsl:with-param name="file" select="$file2"/>
            </xsl:call-template>
        </output>
    </xsl:template>
    
    <xsl:template name="load-file">
        <xsl:param name="file"/>
        <xsl:apply-templates select="doc($file)/input/structure">
            <xsl:with-param name="file" select="$file"/>
        </xsl:apply-templates>
    </xsl:template>
    
    <xsl:template match="structure">
        <xsl:param name="file"/>
        <xsl:copy>
            <xsl:attribute name="origin">
              <xsl:value-of select="concat('doc', substring-after(substring-before($file, '.xml'), 'file'))"/>
        </xsl:attribute>
            <xsl:apply-templates select="@*|node()"/>
        </xsl:copy>
    </xsl:template>
    
</xsl:stylesheet>

edited Jan 11, 2022 at 17:16

answered Dec 30, 2021 at 15:41

Mads Hansen

67.6k12 gold badges119 silver badges154 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

aronadaal Over a year ago

Thanks @mads for your answer and sorry for the delay cause of the holidays. I understood your answer as far as that now both files are processed by xsl:copy-of one after the other and a single output is created. But I still do not understand how I can use the origin attribute with doc1 / doc2 (this should not be the filename). Sorry if my question was not clearly expressed.

Mads Hansen Over a year ago

whoops, looks like I glossed over that important detail in the output! I'll update the answer.

aronadaal Over a year ago

Thanks again for your fast reply. The origin-string must be a separate string. It has nothing in common with the filename and is not derived from it. This is my main problem. The extracted structures should be enriched with a string defined by myself and this string (e.g. doc1/doc2) should be hard coded. Sorry again if I did not communicate clearly. And XSLT2.0 is completely sufficient.

Mads Hansen Over a year ago

Same concept applies. You could add another param for your @origin value and either hard-code or derive from the filename.

Mads Hansen Over a year ago

I have updated with examples of how to snag the numeric value from the filenames.

Collectives™ on Stack Overflow

XSLT Processing two input files into one output file

1 Answer 1

5 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

5 Comments

Your Answer

Sign up or log in

Post as a guest

Related