BI Publisher and XSLT: Advanced Transformation Techniques

When to use XSL-FO over RTF

RTF templates are excellent for most reports. Use XSL-FO (XSLT Formatting Objects) when you need:

• Pixel-perfect multi-column layouts
• Complex running headers/footers that differ by page
• Fixed-position elements (watermarks, background images)
• Reports that mix portrait and landscape sections
• Precise control over pagination

XSL-FO basics

XSL-FO is an XML vocabulary for describing page layouts. BIP processes it using the Apache FOP engine:

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:fo="http://www.w3.org/1999/XSL/Format">

<xsl:template match="/">
  <fo:root>
    <fo:layout-master-set>
      <fo:simple-page-master master-name="A4"
        page-height="29.7cm" page-width="21cm"
        margin-top="2cm" margin-bottom="2cm"
        margin-left="2.5cm" margin-right="2.5cm">
        <fo:region-body margin-top="1cm" margin-bottom="1cm"/>
        <fo:region-before extent="1cm"/>
        <fo:region-after extent="1cm"/>
      </fo:simple-page-master>
    </fo:layout-master-set>
    
    <fo:page-sequence master-reference="A4">
      <fo:static-content flow-name="xsl-region-before">
        <!-- Header content -->
        <fo:block font-size="10pt" color="grey">
          Company Confidential — <fo:inline><xsl:value-of select="//REPORT_DATE"/></fo:inline>
        </fo:block>
      </fo:static-content>
      
      <fo:flow flow-name="xsl-region-body">
        <!-- Main content -->
        <xsl:for-each select="//EMPLOYEES/EMPLOYEE">
          <fo:block font-size="11pt">
            <xsl:value-of select="NAME"/>
          </fo:block>
        </xsl:for-each>
      </fo:flow>
    </fo:page-sequence>
  </fo:root>
</xsl:template>
</xsl:stylesheet>

BIP’s simplified XSL syntax

BIP supports its own simplified tag syntax that can be embedded in XSL-FO:

<?for-each:EMPLOYEES?> ... <?end for-each?>
<?EMPLOYEE_NAME?>
<?xdofx:to_char(AMOUNT, '$999,999')?>

These are preprocessed by BIP before being passed to the FO processor.

Tables in XSL-FO

<fo:table width="100%">
  <fo:table-column column-width="30%"/>
  <fo:table-column column-width="40%"/>
  <fo:table-column column-width="30%"/>
  <fo:table-header>
    <fo:table-row>
      <fo:table-cell><fo:block font-weight="bold">Employee</fo:block></fo:table-cell>
      <fo:table-cell><fo:block font-weight="bold">Department</fo:block></fo:table-cell>
      <fo:table-cell><fo:block font-weight="bold">Salary</fo:block></fo:table-cell>
    </fo:table-row>
  </fo:table-header>
  <fo:table-body>
    <?for-each:EMPLOYEES?>
    <fo:table-row>
      <fo:table-cell><fo:block><?EMPLOYEE_NAME?></fo:block></fo:table-cell>
      <fo:table-cell><fo:block><?DEPT_NAME?></fo:block></fo:table-cell>
      <fo:table-cell text-align="right"><fo:block><?SALARY?></fo:block></fo:table-cell>
    </fo:table-row>
    <?end for-each?>
  </fo:table-body>
</fo:table>