Xpath 'instance of' not working in solr xslt -

i want use xslt in solr output result in json without specific solr attributes.

    {       "techproducts": [          {             "id": "gb18030test",             "price": "0.0"          },          {             "id": "solr1000",             "price": "0.0"          },          {             "id": "utf8test",             "price": "0.0"          }       ],       "paging": {         "count": 3       }     } 

the test of type of field (numeric or boolean) test=". instance of xs:integer" in order add or not quotes do not work , generate 500 error.

http://localhost:8090/solr/techproducts/select?q=*&fq=price:0&fl=id,price&wt=xslt&tr=json_paginate.xsl   caused by: javax.xml.transform.transformerconfigurationexception: solrres:/xslt/json_paginate.xsl: line 37: attribut 'test' obligatoire manquant. 

any suggestions?

<?xml version="1.0" encoding="utf-8"?> <xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/xsl/transform" xmlns:xs="http://www.w3.org/2001/xmlschema" >    <xsl:strip-space elements="*"/>   <xsl:output method="text" indent="no" media-type="application/json"/>      <xsl:template match='/'>         <xsl:text>{"techproducts":[</xsl:text>         <xsl:apply-templates select="response/result/doc"/>         <xsl:text>],</xsl:text>         <xsl:text>"paging":{"count":</xsl:text><xsl:value-of select="response/result/@numfound"/><xsl:text>}}</xsl:text>     </xsl:template>     <xsl:template match="doc">      <xsl:variable name="pos" select="position()"/>     <xsl:if test="position() &gt; 1">         <xsl:text>,</xsl:text>        </xsl:if>      <xsl:text>{</xsl:text>         <xsl:apply-templates>             <xsl:with-param name="pos"><xsl:value-of select="$pos"/></xsl:with-param>         </xsl:apply-templates>     <xsl:text>}</xsl:text>   </xsl:template>    <xsl:template match="doc/*">     <xsl:if test="position() &gt; 1">         <xsl:text>,</xsl:text>        </xsl:if>     <xsl:text>"</xsl:text><xsl:value-of select="@name"/><xsl:text>":</xsl:text>      <xsl:choose>         <!-- if integer, not add quotes -->         <xsl:when test=". instance of xs:integer">             <xsl:value-of select="."/>         </xsl:when>         <!-- if boolean, not add quotes -->         <xsl:when test=". instance of xs:boolean">             <xsl:value-of select="."/>         </xsl:when>         <xsl:otherwise>             <xsl:text>"</xsl:text><xsl:value-of select="."/><xsl:text>"</xsl:text>                   </xsl:otherwise>     </xsl:choose>    </xsl:template> </xsl:stylesheet> 

to solve problem : have upgraded xslt version in solr http://wiki.apache.org/solr/xsltresponsewriter , used

<xsl:choose>     <!-- if decimal, not add quotes -->     <xsl:when test=". castable xs:decimal">         <xsl:value-of select="."/>     </xsl:when>     <!-- if boolean, not add quotes -->     <xsl:when test=". castable xs:boolean">         <xsl:value-of select="."/>     </xsl:when>     <xsl:otherwise>         <xsl:text>"</xsl:text><xsl:value-of select="."/><xsl:text>"</xsl:text>               </xsl:otherwise> </xsl:choose> 

your goal achieve syntactically correct json data: no quotes numbers , strings "true" , "false". that's attempt handling these data types tells me.

in case following xsl:choose part should work - @ least hope so, since don't know input data:

xslt-2.0: (*)

  <xsl:choose>       <!-- if number, not add quotes -->       <xsl:when test="number(.)">           <xsl:value-of select="."/>       </xsl:when>       <!-- if boolean, not add quotes -->       <xsl:when test="matches(.,'true|false','i')">           <xsl:value-of select="lower-case(.)"/>       </xsl:when>       <xsl:otherwise>           <xsl:text>"</xsl:text><xsl:value-of select="."/><xsl:text>"</xsl:text>                 </xsl:otherwise>   </xsl:choose> 

it should mentioned (see comments) numbers printed without quotation marks. not integers. should ok valid json output.

(*) first version of answer had remarkable amount of errors in apologize (downvoting answer quite appropriate). version shown above has been tested saxon , worked expected.