Dynamic grouping on element and attributes names

Question

I would like to categorize results from an XPath under headings by element name (and then by same attribute names). Note: XML data could be inconsistent and some elements with t

Answer 1

This transformation doesn't make any assumptions about the sets having the same number of attributes -- no assumptions at all.

<xsl:stylesheet version="1.0"
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
 xmlns:ext="http://exslt.org/common"
 exclude-result-prefixes="ext">
 <xsl:output omit-xml-declaration="yes" indent="yes"/>
 <xsl:key name="kAnimalByProperties" match="animal"
  use="concat(@atype, .)"/>

 <xsl:variable name="vrtfNewDoc">
  <xsl:apply-templates select="/pets/*">
    <xsl:sort select="name()"/>
  </xsl:apply-templates>
 </xsl:variable>

 <xsl:template match="pets/*">
   <animal atype="{name()}">
     <xsl:copy-of select="@*"/>
     <xsl:for-each select="@*">
       <xsl:sort select="name()"/>
         <attrib>|<xsl:value-of select="name()"/>|</attrib>
     </xsl:for-each>
   </animal>
 </xsl:template>

 <xsl:template match="/">
   <xsl:for-each select="ext:node-set($vrtfNewDoc)">
     <xsl:for-each select=
     "*[generate-id()
       =generate-id(key('kAnimalByProperties',
                        concat(@atype, .)
                        )[1]
                    )
       ]">
        <table border="1">
          <tr>
            <td>Element Name</td>
            <xsl:for-each select="*">
              <td><xsl:value-of select="translate(.,'|','')"/></td>
            </xsl:for-each>
          </tr>
          <xsl:for-each select=
          "key('kAnimalByProperties', concat(@atype, .))">
            <xsl:variable name="vcurAnimal" select="."/>
            <tr>
              <td><xsl:value-of select="@atype"/></td>
              <xsl:for-each select="*">
                <td>
                  <xsl:value-of select=
                   "$vcurAnimal/@*[name()=translate(current(),'|','')]"/>
                </td>
              </xsl:for-each>
            </tr>
          </xsl:for-each>
        </table>
        <p/>
     </xsl:for-each>
   </xsl:for-each>
 </xsl:template>
</xsl:stylesheet>

When applied on the provided XML document:

<pets>
    <dog name="Frank" cute="yes" color="brown" type="Lab"/>
    <cat name="Fluffy" cute="yes" color="brown"/>
    <cat name="Lucy" cute="no" color="brown"/>
    <dog name="Spot" cute="no" color="brown"/>
    <dog name="Rover" cute="yes" color="brown"/>
    <dog name="Rupert" cute="yes" color="beige" type="Pug"/>
    <cat name="Simba" cute="yes" color="grey"/>
    <cat name="Princess" color="brown"/>
</pets>

the wanted, correct result is produced:

<table border="1">
   <tr>
      <td>Element Name</td>
      <td>color</td>
      <td>cute</td>
      <td>name</td>
   </tr>
   <tr>
      <td>cat</td>
      <td>brown</td>
      <td>yes</td>
      <td>Fluffy</td>
   </tr>
   <tr>
      <td>cat</td>
      <td>brown</td>
      <td>no</td>
      <td>Lucy</td>
   </tr>
   <tr>
      <td>cat</td>
      <td>grey</td>
      <td>yes</td>
      <td>Simba</td>
   </tr>
</table>
<p/>
<table border="1">
   <tr>
      <td>Element Name</td>
      <td>color</td>
      <td>name</td>
   </tr>
   <tr>
      <td>cat</td>
      <td>brown</td>
      <td>Princess</td>
   </tr>
</table>
<p/>
<table border="1">
   <tr>
      <td>Element Name</td>
      <td>color</td>
      <td>cute</td>
      <td>name</td>
      <td>type</td>
   </tr>
   <tr>
      <td>dog</td>
      <td>brown</td>
      <td>yes</td>
      <td>Frank</td>
      <td>Lab</td>
   </tr>
   <tr>
      <td>dog</td>
      <td>beige</td>
      <td>yes</td>
      <td>Rupert</td>
      <td>Pug</td>
   </tr>
</table>
<p/>
<table border="1">
   <tr>
      <td>Element Name</td>
      <td>color</td>
      <td>cute</td>
      <td>name</td>
   </tr>
   <tr>
      <td>dog</td>
      <td>brown</td>
      <td>no</td>
      <td>Spot</td>
   </tr>
   <tr>
      <td>dog</td>
      <td>brown</td>
      <td>yes</td>
      <td>Rover</td>
   </tr>
</table>
<p/>

Answer 2

This stylesheet:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <xsl:key name="ByName-AttNum" match="*/*[@color='brown']" use="concat(name(),'++',count(@*))"/>
    <xsl:template match="/">
        <html>
            <xsl:apply-templates/>
        </html>
    </xsl:template>
    <xsl:template match="*/*[generate-id(.) = generate-id(key('ByName-AttNum',concat(name(),'++',count(@*)))[1])]">
        <table>
            <tr>
                <th>ElementName</th>
                <xsl:apply-templates select="@*" mode="headers">
                    <xsl:sort select="name()"/>
                </xsl:apply-templates>
            </tr>
            <xsl:apply-templates select="key('ByName-AttNum',concat(name(),'++',count(@*)))" mode="list"/>
        </table>
    </xsl:template>
    <xsl:template match="*" mode="list">
        <tr>
            <td>
                <xsl:value-of select="name()"/>
            </td>
            <xsl:apply-templates select="@*" mode="list">
                <xsl:sort select="name()"/>
            </xsl:apply-templates>
        </tr>
    </xsl:template>
    <xsl:template match="@*" mode="headers">
        <th>
            <xsl:value-of select="name()"/>
        </th>
    </xsl:template>
    <xsl:template match="@*" mode="list">
        <td>
            <xsl:value-of select="."/>
        </td>
    </xsl:template>
</xsl:stylesheet>

Result:

<html>
    <table>
        <tr>
            <th>ElementName</th>
            <th>color</th>
            <th>cute</th>
            <th>name</th>
            <th>type</th>
        </tr>
        <tr>
            <td>dog</td>
            <td>brown</td>
            <td>yes</td>
            <td>Frank</td>
            <td>Lab</td>
        </tr>
    </table>
    <table>
        <tr>
            <th>ElementName</th>
            <th>color</th>
            <th>cute</th>
            <th>name</th>
        </tr>
        <tr>
            <td>cat</td>
            <td>brown</td>
            <td>yes</td>
            <td>Fluffy</td>
        </tr>
        <tr>
            <td>cat</td>
            <td>brown</td>
            <td>no</td>
            <td>Lucy</td>
        </tr>
    </table>
    <table>
        <tr>
            <th>ElementName</th>
            <th>color</th>
            <th>cute</th>
            <th>name</th>
        </tr>
        <tr>
            <td>dog</td>
            <td>brown</td>
            <td>no</td>
            <td>Spot</td>
        </tr>
        <tr>
            <td>dog</td>
            <td>brown</td>
            <td>yes</td>
            <td>Rover</td>
        </tr>
    </table>
    <table>
        <tr>
            <th>ElementName</th>
            <th>color</th>
            <th>name</th>
        </tr>
        <tr>
            <td>cat</td>
            <td>brown</td>
            <td>Princess</td>
        </tr>
    </table>
</html>

Note: This assumes that all elements having the same number of attributes have also the same attribute's name (like in your input sample).

EDIT: Better ouput markup.

EDIT 2: Another kind of solution: one header with all posible attribute (like CSV pattern) and order element by attribute count and name.

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <xsl:key name="attrByName" match="pets/*/@*" use="name()"/>
    <xsl:variable name="attr" select="/pets/*/@*[count(.|key('attrByName',name())[1])=1]"/>
    <xsl:template match="pets">
        <html>
            <table>
                <tr>
                    <th>ElementName</th>
                    <xsl:apply-templates select="$attr" mode="headers">
                        <xsl:sort select="name()"/>
                    </xsl:apply-templates>
                </tr>
                <xsl:apply-templates select="*[@color='brown']">
                    <xsl:sort select="count(@*)" order="descending"/>
                    <xsl:sort select="name()"/>
                </xsl:apply-templates>
            </table>
        </html>
    </xsl:template>
    <xsl:template match="pets/*">
        <tr>
            <td>
                <xsl:value-of select="name()"/>
            </td>
            <xsl:apply-templates select="$attr" mode="list">
                <xsl:sort select="name()"/>
                <xsl:with-param name="node" select="."/>
            </xsl:apply-templates>
        </tr>
    </xsl:template>
    <xsl:template match="@*" mode="headers">
        <th>
            <xsl:value-of select="name()"/>
        </th>
    </xsl:template>
    <xsl:template match="@*" mode="list">
        <xsl:param name="node"/>
        <td>
            <xsl:value-of select="$node/@*[name()=name(current())]"/>
        </td>
    </xsl:template>
</xsl:stylesheet>

Result:

<html>
    <table>
        <tr>
            <th>ElementName</th>
            <th>color</th>
            <th>cute</th>
            <th>name</th>
            <th>type</th>
        </tr>
        <tr>
            <td>dog</td>
            <td>brown</td>
            <td>yes</td>
            <td>Frank</td>
            <td>Lab</td>
        </tr>
        <tr>
            <td>cat</td>
            <td>brown</td>
            <td>yes</td>
            <td>Fluffy</td>
            <td></td>
        </tr>
        <tr>
            <td>cat</td>
            <td>brown</td>
            <td>no</td>
            <td>Lucy</td>
            <td></td>
        </tr>
        <tr>
            <td>dog</td>
            <td>brown</td>
            <td>no</td>
            <td>Spot</td>
            <td></td>
        </tr>
        <tr>
            <td>dog</td>
            <td>brown</td>
            <td>yes</td>
            <td>Rover</td>
            <td></td>
        </tr>
        <tr>
            <td>cat</td>
            <td>brown</td>
            <td></td>
            <td>Princess</td>
            <td></td>
        </tr>
    </table>
</html>

Note: This runs through the tree twice but without extension. Exact match for desired output without extensions would require to mimic key mechanism like this: run through the tree adding new keys (name of element plus attributes' names) to a param, then again for every key run through the tree filtering node by key (could be a little optimization keeping a node set for non matching elements...). Worst case (every node with distinc key) will pass trough a node: N (for key building) + (N + 1) * N / 2