Greetings,
I am having a difficulty creating a XPath element.
Tiny Example XML document:
<?xml version="1.0" encoding="UTF-8"?>
<catalog name="MasterCatalog">
<service name="WCS" base="/opendap/wcs_service/"/>
<dataset name="Foo" urlPath="data/foo" >
<serviceName>WCS</serviceName>
</dataset>
</catalog>
This works:
<xsl:value-of select="//service[@name='WCS']/@base" /><br />
It returns the value of the attribute "base" for the first "service"
element in the document whose "name" attribute evaluates to "WCS"
However, in my problem when processing a "dataset" element there is a
child
element that contains the name of the service:
I need to get the "base" attribute for the "service" that matches the
text
value of the "serviceName" element.
I thought that I should be able to do it by calling for the value-of the
serviceName element inside the XPath for the select::
<xsl:template match="dataset">
<xsl:value-of select="(//service/[@name='{serviceName}']/
@base" />
</xsl:template-match>
But that doesn't work.
Question 1): Should that work? Is it just an XPath syntax error on my
part, or
must the value of the equality test [@name='stuff'] be hard wired?
Question 2): Is there another way to get to the same place?
I can kludge it using a named template, but I think it's (a) fragile
and (b) ugly.
Thanks in Advance!
Nathan Potter
Complete Example:
Example source XML:
<?xml version="1.0" encoding="UTF-8"?>
<catalog name="MasterCatalog">
<service name="OPeNDAP-Hyrax" base="/opendap/"/>
<service name="WCS" base="/opendap/wcs_service/"/>
<dataset name="Surface Air Temperature"
urlPath="data/TSurfAir" >
<serviceName>OPeNDAP-Hyrax</serviceName>
</dataset>
<dataset name="Foo" urlPath="data/foo" >
<serviceName>WCS</serviceName>
</dataset>
<dataset name="SeaSurfaceTemperature"
urlPath="data/sst">
<serviceName>WCS</serviceName>
</dataset>
</catalog>
Example XSLT:
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE xsl:stylesheet []>
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
>
<xsl:output method='html' version='1.0' encoding='UTF-8'
indent='yes'/>
<xsl:template match="catalog">
<html>
<xsl:apply-templates />
</html>
</xsl:template>
<xsl:template match="dataset">
<xsl:if test="not(dataset)"><!-- Otherwise, create the
access link. -->
<!-- This Works, but it's hardwired for the same result
every time: -->
service: <xsl:value-of select="//service[@name='WCS']/
@base" /><br/>
<!-- This does not. Is there a way to get there? -->
service: <xsl:value-of select="//service
[@name='{serviceName}']/base" /><br/>
<!-- And this is a nasty workaround -->
<xsl:call-template name="accessURL">
<xsl:with-param name="serviceName"><xsl:value-of
select="serviceName" /></xsl:with-param>
<xsl:with-param name="urlPath"><xsl:value-of
select="@urlPath" /></xsl:with-param>
<xsl:with-param name="name"><xsl:value-of
select="@name" /></xsl:with-param>
<xsl:with-param name="suffix">html</xsl:with-param>
</xsl:call-template><br/>
</xsl:if>
</xsl:template>
<xsl:template name="accessURL">
<xsl:param name="serviceName" />
<xsl:param name="urlPath" />
<xsl:param name="name" />
<xsl:param name="suffix" />
<xsl:for-each select="//service">
<xsl:if test="@name = $serviceName">
<a href="{@base}{$urlPath}.{$suffix}" > <xsl:value-
of select="$name" /></a>
</xsl:if>
</xsl:for-each>
</xsl:template>
<xsl:template match="serviceName">
<xsl:param name="indent" />
</xsl:template>
</xsl:stylesheet>
============================================================
Nathan Potter Oregon State University, COAS