XQuery/XSL-FO Tables
Motivation
[edit | edit source]You want to be able to create high-quality tabular outputs suitable for book-publishing.
Method
[edit | edit source]To accomplish this we will convert our XML into XSL-FO tables. Unlike HTML, XML-FO allows you to create flows of text and you can set up rules on how objects span page boundaries.
Sample Input
[edit | edit source]Here is a sample XML file that contains a table with two columns.
<table heading="Department Phone Extensions">
<Person>
<Name>John Doe</Name>
<Extension>1234</Extension>
</Person>
<Person>
<Name>Sue Smith</Name>
<Extension>5678</Extension>
</Person>
<Person>
<Name>John Doe</Name>
<Extension>1234</Extension>
</Person>
<Person>
<Name>Sue Smith</Name>
<Extension>5678</Extension>
</Person>
<Person>
<Name>John Doe</Name>
<Extension>1234</Extension>
</Person>
<Person>
<Name>Sue Smith</Name>
<Extension>5678</Extension>
</Person>
<Person>
<Name>John Doe</Name>
<Extension>1234</Extension>
</Person>
<Person>
<Name>Sue Smith</Name>
<Extension>5678</Extension>
</Person>
<Person>
<Name>John Doe</Name>
<Extension>1234</Extension>
</Person>
<Person>
<Name>Sue Smith</Name>
<Extension>5678</Extension>
</Person>
<Person>
<Name>John Doe</Name>
<Extension>1234</Extension>
</Person>
<Person>
<Name>Sue Smith</Name>
<Extension>5678</Extension>
</Person>
<Person>
<Name>John Doe</Name>
<Extension>1234</Extension>
</Person>
<Person>
<Name>Sue Smith</Name>
<Extension>5678</Extension>
</Person>
<Person>
<Name>John Doe</Name>
<Extension>1234</Extension>
</Person>
<Person>
<Name>Sue Smith</Name>
<Extension>5678</Extension>
</Person>
<Person>
<Name>John Doe</Name>
<Extension>1234</Extension>
</Person>
<Person>
<Name>Sue Smith</Name>
<Extension>5678</Extension>
</Person>
<Person>
<Name>John Doe</Name>
<Extension>1234</Extension>
</Person>
<Person>
<Name>Sue Smith</Name>
<Extension>5678</Extension>
</Person>
<Person>
<Name>John Doe</Name>
<Extension>1234</Extension>
</Person>
<Person>
<Name>Sue Smith</Name>
<Extension>5678</Extension>
</Person>
</table>
We would like this XML file to be rendered with two columns, the first containing the person's name and the second their phone extension. It should look like the following.
Name | Extension |
---|---|
John Doe | 1234 |
Sue Smith | 5678 |
Example FO File
[edit | edit source]The following is the core of the XML-FO layout that you will need to create the table (without control on the column widths).
<fo:block xmlns:fo="http://www.w3.org/1999/XSL/Format">
<fo:block font-size="14pt" padding="10px" font-family="Verdana">Department Phone Extensions</fo:block>
<fo:block font-size="10pt">
<fo:table border="solid" border-collapse="collapse">
<fo:table-header>
<fo:table-row space-after="10px">
<fo:table-cell>
<fo:block font-weight="bold">Name</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block font-weight="bold">Extension</fo:block>
</fo:table-cell>
</fo:table-row>
</fo:table-header>
<fo:table-body>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>John Doe</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>1234</fo:block>
</fo:table-cell>
</fo:table-row>
<fo:table-row>
<fo:table-cell>
<fo:block>Sue Smith</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>5678</fo:block>
</fo:table-cell>
</fo:table-row>
</fo:table-body>
</fo:table>
</fo:block>
</fo:block>
Transform with XQuery
[edit | edit source]Transform with XSLT
[edit | edit source]NOTE: This example should be moved to a book on XSLT. XQuery typeswitch transforms should be used to do this.
We can transform the XML structure to XSL-FO using an XSLT script. This generic script only requires that the root of the XML table is called table with a heading attribute.
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:fo="http://www.w3.org/1999/XSL/Format"
exclude-result-prefixes="xs" version="2.0">
<xsl:template match="/table">
<fo:block>
<fo:block font-size="14pt" padding="10px" font-family="Verdana">
<xsl:value-of select="@heading"/>
</fo:block>
<fo:block font-size="10pt">
<fo:table border="solid" border-collapse="collapse" >
<fo:table-header>
<fo:table-row>
<xsl:for-each select="*[1]/*">
<fo:table-cell>
<fo:block font-weight="bold">
<xsl:value-of select="name(.)"/>
</fo:block>
</fo:table-cell>
</xsl:for-each>
</fo:table-row>
</fo:table-header>
<fo:table-body>
<xsl:apply-templates select="*"/>
</fo:table-body>
</fo:table>
</fo:block>
</fo:block>
</xsl:template>
<xsl:template match="*">
<fo:table-row>
<xsl:for-each select="*">
<fo:table-cell>
<fo:block>
<xsl:value-of select="."/>
</fo:block>
</fo:table-cell>
</xsl:for-each>
</fo:table-row>
</xsl:template>
</xsl:stylesheet>
XQuery integration
[edit | edit source]Finally we can generate the full XSL-FO document and render as PDF with an XQuery script. We use the XSLT to transform the table, and then embed that XSL-FO fragment in the XSL-FO master before rendering as PDF and streaming the binary document. There are of course other ways to assemble the full XSLT-FO document.
xquery version "1.0";
import module namespace xslfo="http://exist-db.org/xquery/xslfo";
import module namespace transform="http://exist-db.org/xquery/transform";
declare namespace fo="http://www.w3.org/1999/XSL/Format";
let $table :=
<table heading="Department Phone Extensions">
<Person>
<Name>John Doe</Name>
<Extension>1234</Extension>
</Person>
<Person>
<Name>Doe John</Name>
<Extension>4321</Extension>
</Person>
<Person>
<Name><span style="color: #f00;">Sue Smith</span></Name>
<Extension>5678</Extension>
</Person>
</table>
let $table-fo := transform:transform($table,doc("/db/Wiki/eXist/xsl-fo/table2fo.xsl"),())
let $fo :=
<fo:root xmlns:fo="http://www.w3.org/1999/XSL/Format">
<fo:layout-master-set>
<fo:simple-page-master master-name="my-page">
<fo:region-body margin="1in"/>
</fo:simple-page-master>
</fo:layout-master-set>
<fo:page-sequence master-reference="my-page">
<fo:flow flow-name="xsl-region-body">
<fo:block>
{$table-fo}
</fo:block>
</fo:flow>
</fo:page-sequence>
</fo:root>
let $pdf := xslfo:render($fo, "application/pdf", ())
return
response:stream-binary($pdf, "application/pdf", "output.pdf")
Database data
[edit | edit source]As a further example, the following XQuery selects all employees and renders them in a PDF table:
xquery version "1.0";
import module namespace xslfo="http://exist-db.org/xquery/xslfo";
import module namespace transform="http://exist-db.org/xquery/transform";
declare namespace fo="http://www.w3.org/1999/XSL/Format";
let $table :=
<table heading="Employees">
{//Emp}
</table>
let $table-fo := transform:transform($table,doc("/db/Wiki/eXist/xsl-fo/table2fo.xsl"),())
let $fo :=
<fo:root xmlns:fo="http://www.w3.org/1999/XSL/Format">
<fo:layout-master-set>
<fo:simple-page-master master-name="my-page">
<fo:region-body margin="1in"/>
</fo:simple-page-master>
</fo:layout-master-set>
<fo:page-sequence master-reference="my-page">
<fo:flow flow-name="xsl-region-body">
<fo:block>
{$table-fo}
</fo:block>
</fo:flow>
</fo:page-sequence>
</fo:root>
let $pdf := xslfo:render($fo, "application/pdf", ())
return
response:stream-binary($pdf, "application/pdf", "output.pdf")