Displaying xml nodes dynamically and applying style to specific nodes using recursion - xslt

Question

Below is my xml file.
<xml>
<top>
<main>
<firstname>John</firstname>
<lastname>John</lastname>
<table></table>
<chapter>
<firstname>Alex</firstname>
<lastname>Robert</lastname>
<p>Sample text chap</p>
<figure name="f1.svg"></figure>
<chapter>
<firstname>Rebec</firstname>
<lastname></lastname>
<p>Sample text</p>
<figure name="f2.svg"></figure>
</chapter>
</chapter>
</main>
</top>
</xml>
Desired output:
<bold>John
table
<bold>Robert
Sample text chap
f1.svg
<bold> Rebec
Sample text
f2.svg
Explaination: I have written an xslt to do this. I need to fetch the xml nodes dynamically. I cannot write: xsl:apply-templates select='main/lastname'. Because my xml format could change anytime.
I have tried a logic to first fetch all the xml nodes using '$root/*'. Then if 'table' element is encountered, i use xsl:apply-templates select='current()[name() = 'TABLE']' and perform table creation operations.
This works fine. I get the desired output but my figure elements only displays f1.svg at every place in the output. f2.svg is not shown.
And how do I match only 'lastname' and make it bold?
I want to make the code as generic/modular as possible so that it loops through all the elements of the xml tree and does some formatting on the specific nodes.
Below is a recursive xslt. With this my data is getting repeated. I am writing recursive template because xslt is not sequential.
XSLT:
<xsl:call-template name="FetchNodes">
<xsl:with-param name="endIndex" select="$NumberOfNodes" />
<xsl:with-param name="startIndex" select="1" />
<xsl:with-param name="context" select="$root/*" />
</xsl:call-template>
<xsl:template name="FetchNodes">
<xsl:param name="endIndex" />
<xsl:param name="startIndex" />
<xsl:param name="context" />
<xsl:if test="$startIndex <= $endIndex">
<xsl:if test="$context[$startIndex][name() = 'table']"">
<xsl:apply-templates select="$context[$startIndex][name() = 'table']"" mode="table" />
</xsl:if>
<xsl:call-template name="FetchNodes">
<xsl:with-param name="endIndex" select="$endIndex" />
<xsl:with-param name="startIndex" select="$startIndex + 1"/>
<xsl:with-param name="context" select="$context" />
</xsl:call-template>
</xsl:if>
</xsl:template>
<xsl:template match="node()" mode="table">
<xsl:value-of select="node()" />
</xsl:template>
With the above xslt, something is incorrect in the xpath of apply templates. Output is not proper.
I want XSL FO output.
Can anybody suggest something?

Answer 1

The problem it displaying "f1.svg" instead of "f2.svg" is because of this line
<xsl:variable name="ImageName">
<xsl:value-of select="$root/*/chapter/figure/#name" />
</xsl:variable>
You are already positioned on a figure at this point, so you only need to use a relative xpath expression here. The one you are currently using is an absolute path and so will always return the first #name attribute regardless of your context. It should look this this
<xsl:variable name="ImageName">
<xsl:value-of select="#name" />
</xsl:variable>
Or better still, like this
<xsl:variable name="ImageName" select="#name" />
Having said, the code is in a template that is trying to match an element a FIGURE element, which does not exist in the XML you have shown us. You can actually simplify the template match to this, for example
<xsl:template match="figure" mode="figure">
As for making things bold, you can just add the font-weight attribute to any block you want to make bold. Something like this:
<xsl:choose>
<xsl:when test="self::lastname">
<fo:inline font-weight="bold"><xsl:value-of select="text()" /></fo:inline>
</xsl:when>
<xsl:otherwise>
<xsl:value-of select="text()" />
</xsl:otherwise>
</xsl:choose>
EDIT: Having said all that, you may not be taking the correct approach to the problem. It may be better to use template matching, taking advantage of XSLT's built-in template to navigate over the document. Essentially, just write a template for each element you want to match, and generate the output, and then carry on matching its children.
For example, to turn a chapter into an fo:block do this
<xsl:template match="chapter">
<fo:block>
<xsl:apply-templates/>
</fo:block>
</xsl:template>
To output the firstname in bold, do this
<xsl:template match="firstname">
<fo:inline font-weight="bold">
<xsl:value-of select="text()"/>
</fo:inline>
</xsl:template>
To turn a figure into an image, do this (Note the use of Attribute Value Templates here, the curly braces indicate an expression to be evaluated, not output literally)
<xsl:template match="figure">
<fo:block>
<fo:external-graphic src="../resources/{#name}" content-height="60%" scaling="uniform" padding-left="2cm"/>
</fo:block>
</xsl:template>
Try this XSLT as a starting point, and build on it
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:fo="http://www.w3.org/1999/XSL/Format">
<xsl:output method="xml" indent="yes"/>
<xsl:template match="main">
<fo:block>
<xsl:apply-templates/>
</fo:block>
</xsl:template>
<xsl:template match="chapter">
<fo:block>
<xsl:apply-templates/>
</fo:block>
</xsl:template>
<xsl:template match="firstname">
<fo:inline font-weight="bold">
<xsl:value-of select="text()"/>
</fo:inline>
</xsl:template>
<xsl:template match="lastname"/>
<xsl:template match="figure">
<fo:block>
<fo:external-graphic src="../resources/{#name}" content-height="60%" scaling="uniform" padding-left="2cm"/>
</fo:block>
</xsl:template>
</xsl:stylesheet>