convert xml document to comma delimited (CSV) file

Question

I need some assistance converting an xml document to a CSV file using an xslt stylesheet. I am trying to use the following xsl and I can't seem to get it right. I want my comma delimited file to include column headings, followed by the data. My biggest issues are removing the final comma after the last item and inserting a carriage return so each group of data appears on a separate line. I have been using XML Notepad.

  <xsl:template match="/">
        <xsl:element name="table">
              <xsl:apply-templates select="/*/*[1]" mode="header" />
              <xsl:apply-templates select="/*/*" mode="row" />
        </xsl:element>
  </xsl:template>

  <xsl:template match="*" mode="header">
        <xsl:element name="tr">
              <xsl:apply-templates select="./*" mode="column" />
        </xsl:element>
  </xsl:template>

  <xsl:template match="*" mode="row">
        <xsl:element name="tr">
              <xsl:apply-templates select="./*" mode="node" />
        </xsl:element>
  </xsl:template>

  <xsl:template match="*" mode="column">
        <xsl:element name="th">
              <xsl:value-of select="translate(name(.),'qwertyuiopasdfghjklzxcvbnm_','QWERTYUIOPASDFGHJKLZXCVBNM ')" />
        </xsl:element>,
  </xsl:template>

  <xsl:template match="*" mode="node">
        <xsl:element name="td">
              <xsl:value-of select="." />
        </xsl:element>,
  </xsl:template> 

Answer 1

I was using the "more thorough transform" of the xslt from @flynn1179 's answer.. but found that it was taking an extraordinary amount of time when the number of rows increased. (this is using oracle dbms_xmlgen xslt transform )

I found that because I know what my 2 levels of data are called (ROWSET and ROW in this case) i was able to optimize the xslt and gain a significant performance increase.

My modified version (specifically aimed at oracle's dbms_xmlgen package) is below. it also includes bits from other csv transforms I found around the internet.

<xsl:stylesheet  version="1.0"  xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:output method="text" encoding="utf-8"/>
 <xsl:strip-space elements="*"/>

 <!-- some variables for unprintable charcaters -->
<xsl:variable name="CRLF">  
  <xsl:text>&#13;&#10;</xsl:text>  
</xsl:variable>  
<xsl:variable name="CR">  
  <xsl:text>&#13;</xsl:text>  
</xsl:variable>  
<xsl:variable name="LF">  
  <xsl:text>&#10;</xsl:text>  
</xsl:variable>  
<xsl:variable name="apos">'</xsl:variable>

<xsl:template match="/ROWSET">
<xsl:for-each select="ROW[1]/*">
  <xsl:value-of select="local-name()" />
  <xsl:if test="position() != last()">,</xsl:if>
</xsl:for-each>
<xsl:value-of select="$LF"/>
<xsl:apply-templates />
</xsl:template>

<xsl:template match="ROW">
  <xsl:apply-templates />
  <xsl:value-of select="$LF"/>
</xsl:template>

<xsl:template match="ROW/*">
  <xsl:choose>
  <xsl:when test="contains( text(), ',' ) or   
                  contains( text(), $apos ) or  
                  contains( text(), $CRLF ) or  
                  contains( text(), $CR ) or  
                  contains( text(), $LF )">
    <!-- Field contains a comma, apostrophe and/or a linefeed, so quote --> 
    <xsl:text>&quot;</xsl:text>
    <xsl:call-template name="doublequotes">
      <xsl:with-param name="text" select="text()" />
    </xsl:call-template>
    <xsl:text>&quot;</xsl:text>
  </xsl:when>
  <xsl:otherwise>
    <xsl:value-of select="." />
  </xsl:otherwise>
</xsl:choose>
<xsl:if test="position() != last()">,</xsl:if>
</xsl:template>

<xsl:template name="doublequotes">
<xsl:param name="text" />
<xsl:choose> 
  <xsl:when test="contains($text,'&quot;')">
    <!-- recursive call -->
    <xsl:value-of select="concat(substring-before($text,'&quot;'),'&quot;&quot;')" />
    <xsl:call-template name="doublequotes">
      <xsl:with-param name="text" select="substring-after($text,'&quot;')" />
    </xsl:call-template>
  </xsl:when>
  <xsl:otherwise>
    <xsl:value-of select="$text" />
  </xsl:otherwise>
</xsl:choose>
</xsl:template>
</xsl:stylesheet>

Answer 2

I use this to simple XSLT to convert XML to CSV; it assumes all child nodes of the root node are to be rows in the CSV, taking the element names of the first child of the root to be field names.

<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:output method="text"/>

  <xsl:template match="/">
    <xsl:for-each select="*/*[1]/*">
      <xsl:value-of select="name()" />
      <xsl:if test="not(position() = last())">,</xsl:if>
    </xsl:for-each>
    <xsl:text>&#10;</xsl:text>
    <xsl:apply-templates select="*/*" mode="row"/>
  </xsl:template>

  <xsl:template match="*" mode="row">
    <xsl:apply-templates select="*" mode="data" />
    <xsl:text>&#10;</xsl:text>
  </xsl:template>

  <xsl:template match="*" mode="data">
    <xsl:choose>
      <xsl:when test="contains(text(),',')">
        <xsl:text>&quot;</xsl:text>
        <xsl:call-template name="doublequotes">
          <xsl:with-param name="text" select="text()" />
        </xsl:call-template>
        <xsl:text>&quot;</xsl:text>
      </xsl:when>
      <xsl:otherwise>
        <xsl:value-of select="." />
      </xsl:otherwise>
    </xsl:choose>
    <xsl:if test="position() != last()">,</xsl:if>
  </xsl:template>

  <xsl:template name="doublequotes">
    <xsl:param name="text" />
    <xsl:choose>
      <xsl:when test="contains($text,'&quot;')">
        <xsl:value-of select="concat(substring-before($text,'&quot;'),'&quot;&quot;')" />
        <xsl:call-template name="doublequotes">
          <xsl:with-param name="text" select="substring-after($text,'&quot;')" />
        </xsl:call-template>
      </xsl:when>
      <xsl:otherwise>
        <xsl:value-of select="$text" />
      </xsl:otherwise>
    </xsl:choose>
  </xsl:template>
</xsl:stylesheet>

So this XML:

<csv>
  <row>
    <field1>foo</field1>
    <field2>ba"r</field2>
  </row>
  <row>
    <field1>foo,2</field1>
    <field2>bar,"2</field2>
  </row>
</csv>

Converts to:

field1,field2
foo,ba"r
"foo,2","bar,""2"

Not sure if this helps though, it depends how your XML is laid out.

Edit: Here's a more thorough transform:

<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:key name="field" match="/*/*/*" use="name()" />
  <xsl:output method="text"/>

  <xsl:template match="/">
    <xsl:for-each select="*/*/*[generate-id() = generate-id(key('field',name())[1])]">
      <xsl:value-of select="name()" />
      <xsl:if test="position() != last()">,</xsl:if>
    </xsl:for-each>
    <xsl:text>&#10;</xsl:text>
    <xsl:apply-templates select="*/*" mode="row"/>
  </xsl:template>

  <xsl:template match="*" mode="row">
    <xsl:variable name="row" select="*" />
    <xsl:for-each select="/*/*/*[generate-id() = generate-id(key('field',name())[1])]">
      <xsl:variable name="name" select="name()" />
      <xsl:apply-templates select="$row[name()=$name]" mode="data" />
      <xsl:if test="position() != last()">,</xsl:if>
    </xsl:for-each>
    <xsl:text>&#10;</xsl:text>
  </xsl:template>

  <xsl:template match="*" mode="data">
    <xsl:choose>
      <xsl:when test="contains(text(),',')">
        <xsl:text>&quot;</xsl:text>
        <xsl:call-template name="doublequotes">
          <xsl:with-param name="text" select="text()" />
        </xsl:call-template>
        <xsl:text>&quot;</xsl:text>
      </xsl:when>
      <xsl:otherwise>
        <xsl:value-of select="." />
      </xsl:otherwise>
    </xsl:choose>
    <xsl:if test="position() != last()">,</xsl:if>
  </xsl:template>

  <xsl:template name="doublequotes">
    <xsl:param name="text" />
    <xsl:choose>
      <xsl:when test="contains($text,'&quot;')">
        <xsl:value-of select="concat(substring-before($text,'&quot;'),'&quot;&quot;')" />
        <xsl:call-template name="doublequotes">
          <xsl:with-param name="text" select="substring-after($text,'&quot;')" />
        </xsl:call-template>
      </xsl:when>
      <xsl:otherwise>
        <xsl:value-of select="$text" />
      </xsl:otherwise>
    </xsl:choose>
  </xsl:template>
</xsl:stylesheet>

This one will create a column in your CSV for all tag names that exist in all 'rows', and populate the appropriate column in each row.