Cannot execute xxforms:get-request-parameter in XPL - XSLT processor

Question

I get the error:

XPath syntax error at ... in {...get-request-parameter('query..}:
Cannot find a matching 1-argument function named {http://orbeon.org/oxf/xml/xforms}get-request-parameter(). Note: external function calls have been disabled

when I attempt to execute a pipeline with:

<p:processor name="oxf:xslt">
    <p:input name="config">
        <xsl:stylesheet version="2.0">
            <xsl:template match="/">
                <TargetURL>
                    <xsl:variable name="location" select="/Configuration/XMLDB/Location/text()"/>                           
                    <xsl:variable name="name" select="/Configuration/XMLDB/Name/text()"/>                           
                    <xsl:variable name="query" select="xxforms:get-request-parameter('query')"/>                           
                    <xsl:value-of select="fn:concat($location,'/',$name,'?',$query)"/>
                </TargetURL>
            </xsl:template>
        </xsl:stylesheet>
    </p:input>
    <p:input name="data" href="#configuration"/>
    <p:output name="data" id="Target"/>
</p:processor>

Is XPL not the correct location to retrieve the HTTP request params (should I be doing it in page-flow.xml instead?)

Answer 1

Solved it by using the oxf:request processor in the XPL to retrieve query parameters and provide them on a separate output which is then accessed using oxf:xslt processor, like so:

<p:processor name="oxf:request">
    <p:input name="config">
        <config>
            <include>/request/parameters/parameter[name='param1']</include>
            <include>/request/parameters/parameter[name='param2']</include>
        </config>
    </p:input>
    <p:output name="data" id="request"/>
</p:processor>


<p:processor name="oxf:xslt">
    <p:input name="config">
        <xsl:stylesheet version="2.0">
            <xsl:template match="/">
                <TargetURL>
                    <xsl:variable name="var1" select="doc('input:request')/request/parameters/parameter[name='param1']/value"/>
                    <xsl:variable name="var2" select="doc('input:request')/request/parameters/parameter[name='param2']/value"/>                         
                </TargetURL>
            </xsl:template>
        </xsl:stylesheet>
    </p:input>
    <p:input name="data" href="#configuration"/>
    <p:input name="request" href="#request"/>
    <p:output name="data" id="Target"/>
</p:processor>

Answer 2

xxforms:get-request-parameter() is designed to called from XForms, but you are here calling it from XSLT.

Do you really need to use XPL/XSLT in this case? In most cases, if what you are generating is a web page, you might just be able to use XForms. In your page flow, you point to your XForms with the view attribute, and in your XForms, on xforms-model-construct-done, you can access the request parameters with xxforms:get-request-parameter(), and copy their value somewhere in an instance if necessary.