FrOSCon

Bastian Feder, Thomas Weinert"The Lumber Mill"

Using XSLT For Your Templates

About Us● Application Developer

– PHP– XSLT/XPath– (some) JavaScript

● papaya CMS– PHP based Content Management System– uses XSLT for Templates

About You● Who are you?● Do you use XSLT?● How often do you use XSLT?● Do you use other template systems/languages?● Smarty?● TypoScript?● ...?

Template Systems● Bind variables● Layout logic

– Placeholders– Conditions– Loops– Callbacks

● Formatting● Data loading

XSL● XML

– Semantic variable tree● XPath

– Query language for XML trees● XSLT

– Transforming XML● Conditions● Loops● …

Comparison● PHP based

– Individual syntax– Individual tools– Individual

documentation– Different flavors

for different purpose

– Easy Syntax?

● XSLT– Standardized

syntax– Free and

commercial tools– Documentation of

the standard and the implementations

– One to rule them all

Nodes

Elements Text nodes Attributes* text() @*

node()

● texts/text[@ident='foo']/*● texts/text[@ident='foo']/text()● texts/text[@ident='foo']/node()● texts/text[@ident='foo']/@value

Template call/apply● <xsl:call-template/>

– Call templates by name● <xsl:apply-templates/>

– Template matching– Most exact pattern wins

● Current node● Parameters● Modes

Static Templates Files● Template files should not be writable by the

web server– Security– Tools

● Template files should not be generated from PHP

– Same reasons– Context

Collecting Output

Main (XML)

Part 1 (HTML)

Part 2 (XML)Part 1 (XML)

Part 2 (HTML)

Page (XML)

Page (HTML)

Caching Output

Main (XML)

Part 1 (HTML)

Part 2 (XML)Part 1 (XML)

Part 2 (HTML)

Page (XML)

Page (HTML)

Cache

Embedding Output● Escaping and CDATA-Sections

– CDATA is for readability and whitespaces● <xsl:copy-of select=“...“/>● disable-output-escaping=“yes“● Dangers

– HTML Injection

Import templates● Generic● Reusable● Encapsulation● Inheritance

Multiple Columns Template● Group items

– Calculate positions● Call item group templates● Call item generic template● Use itemType parameter to identify item

template● Call type specific template for item

XML Data Files● Wellformed XML● XPath: document()● URI

– Single loading

Language Templates● Phrases

– "layout texts"● Numbers● Date and Time

EXSLT● Community initiative to provide extensions to

XSLT– Common– Functions– Math, Random– Strings, Regular Expressions– Dates and Times– Sets– Dynamic

EXSLT: functions module● Make templates to functions

– func:function– func:result

● Namespace required– func– Own

PHP● Streamwrapper

– return XML data for document()● Callbacks

– call php source

Streamwrapper● PHP file functions use stream wrappers

– Internal: http, ftp, phar, …● Register own stream wrappers

– PHP class– Basic functions

● stream_open(), stream_read(), stream_tell(), stream_seek(), stream_eof(),

– url_stat()● No php source!

Callbacks● Register PHP functions for xsl

– registerPHPFunctions($restrict)– php::function('function', parameter, ...)– php::functionString('function', ...)

RTF Problem● Result Tree Fragment

– XML created in XSL– No CDATA– No node set

● XSLT 2.0● EXSLT

– node-set()

Other Templates● Repeat String● JavaScript Escaping

ext/xslcache● Process cache● Performance increase● Still evaluating

– Only some checks in php requests● Only static XSLT● Same library like ext/xsl

– eXSLT– PHP callbacks

Administration

● Single template● About 25% saved

Output

● Several template● About 90% saved

Links● http://www.a-basketful-of-papayas.net/

● http://www.w3.org/TR/xpath● http://www.w3.org/TR/xslt● http://www.dpawson.co.uk/xsl/sect2/sect21.html

● http://code.nytimes.com/projects/xslcache/