Beginning

XSLT and XpathTransforming XML Documents and Data

www.wrox.com

$49.99 USA$59.99 CANADA

Recommended Computer Book

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Programming Languages

XML

ISBN: 978-0-470-47725-0

Wrox Beginning guides are crafted to make learning programming languages and technologies easier than you think, providing a structured, tutorial format that will guide you through all the techniques involved.

Extensible Stylesheet Language Transformations (XSLT) is a language for transforming XML documents and data from one format to another. Answering the demand for an introductory book on XSLT processing, Ian Williams presents a clear, concise resource on XSLT concepts and methods and explains how and why XSLT relies on the XML Path language (XPath).

As you gain a solid foundation in XSLT processing, you’ll learn the basic node tree structure that is used in the data model and discover how XSLT differs from the approach used in other programming languages. Example-laden chapters include both versions 1.0 and 2.0 features and demonstrate how to transform one XML data format to another. The book covers the key structural elements of an XSLT file and shows you how to use simple XPath expressions to match and select source file content. Along the way, you’ll uncover a rich set of XPath functions that will benefit you again and again as you develop your XSLT skills.

What you will learn from this book● How to define templates, the basic building blocks of XSLT

● The way to construct XPath expressions and use a range of powerful XPath and XSLT functions

● The role of variables and parameters in XSLT

● Making use of control structures and iteration

● How to generate and format numbers, dates, and times

● Methods for working with multiple source and stylesheet documents

● Ways to debug XSLT, validate types in XSLT, and document your stylesheets

● Tips for indexing and linking items using identifiers and keys

● Techniques for controlling whitespace and processing plain text

Who this book is forThis book is for web developers, authors, and designers who understand XML basics, and are interested in gaining a solid understanding of XSLT processing.

Williams

Beginning

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Updates, source code, and Wrox technical support at www.wrox.com

Beginning

Ian Williams

XSLT and XpathTransforming XML Documents and Data

XS

LT and Xpath Transform

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ocuments and D

ata

Wrox Programmer to Programmer TMWrox Programmer to Programmer TM

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Beginning XSLT and XPathIntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xixChapter 1: First Steps with XSLT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Chapter 2: Introducing XPath . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Chapter 3: Templates, Variables, and Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Chapter 4: Using Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Chapter 5: Sorting and Grouping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Chapter 6: Strings, Numbers, Dates, and Times . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95Chapter 7: Multiple Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115Chapter 8: Processing Text . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141Chapter 9: Identifiers and Keys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159Chapter 10: Debugging, Validation, and Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181Chapter 11: A Case Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201Appendix A: Answers to Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239Appendix B: Extending XSLT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253Appendix C: XSLT Processing Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259Appendix D: XSLT 2.0 Quick Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263Appendix E: XSLT 2.0 Schema . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315Appendix F: XPath 2.0 Function Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341Appendix G: References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 377Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 381Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385

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Beginning

XSLT and XPath

Transforming XML Documents and Data

Ian Williams

Wiley Publishing, Inc.

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Beginning XSLT and XPath: Transforming XML Documentsand DataPublished byWiley Publishing, Inc.10475 Crosspoint BoulevardIndianapolis, IN 46256www.wiley.com

Copyright © 2009 by Ian Williams

Published by Wiley Publishing, Inc., Indianapolis, Indiana

Published simultaneously in Canada

ISBN: 978-0-470-47725-0

Manufactured in the United States of America

10 9 8 7 6 5 4 3 2 1

No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or byany means, electronic, mechanical, photocopying, recording, scanning or otherwise, except as permitted underSections 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of thePublisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center,222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 646-8600. Requests to the Publisher for permissionshould be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030,(201) 748-6011, fax (201) 748-6008, or online at http://www.wiley.com/go/permissions.

Limit of Liability/Disclaimer of Warranty: The publisher and the author make no representations or warrantieswith respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties,including without limitation warranties of fitness for a particular purpose. No warranty may be created or extendedby sales or promotional materials. The advice and strategies contained herein may not be suitable for everysituation. This work is sold with the understanding that the publisher is not engaged in rendering legal, accounting,or other professional services. If professional assistance is required, the services of a competent professional personshould be sought. Neither the publisher nor the author shall be liable for damages arising herefrom. The fact that anorganization or Web site is referred to in this work as a citation and/or a potential source of further informationdoes not mean that the author or the publisher endorses the information the organization or Web site may provideor recommendations it may make. Further, readers should be aware that Internet Web sites listed in this work mayhave changed or disappeared between when this work was written and when it is read.

For general information on our other products and services please contact our Customer Care Department within theUnited States at (877) 762-2974, outside the United States at (317) 572-3993 or fax (317) 572-4002.

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Trademarks: Wiley, the Wiley logo, Wrox, the Wrox logo, Wrox Programmer to Programmer, and related trade dressare trademarks or registered trademarks of John Wiley & Sons, Inc. and/or its affiliates, in the United States andother countries, and may not be used without written permission. All other trademarks are the property of theirrespective owners. Wiley Publishing, Inc., is not associated with any product or vendor mentioned in this book.

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About the AuthorIan Williams is an information designer specializing in XML technologies, and a software technicalwriter. He worked in the U.K. publishing industry before getting involved in information technology atOWL International, developers of the one of the first commercial hypertext products. Ian was a productmanager there, and later a consultant working with large corporate customers.

Since 1998 Ian has worked on technical writing and information-design projects, most recently for Nokia,Reuters, and Volantis. He is co-author with Pierre Greborio of Professional InfoPath 2003, also from WroxPress.

Ian lives with his wife, Helen, in Kent, in a converted lifeboat station overlooking the English Channel.

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CreditsExecutive EditorCarol Long

Development EditorTom Dinse

Technical EditorDan Squier

Production EditorEric Charbonneau

Copy EditorLuann Rouff

Editorial DirectorRobyn B. Siesky

Editorial ManagerMary Beth Wakefield

Production ManagerTim Tate

Vice President and ExecutiveGroup PublisherRichard Swadley

Vice President and Executive PublisherBarry Pruett

Associate PublisherJim Minatel

Project Coordinator, CoverLynsey Stanford

ProofreaderCandace English

IndexerJohnna VanHoose Dinse

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Contents

Introduction xix

Chapter 1: First Steps with XSLT 1

Transforming an XML Document to a Web Page 1Using a Browser 2Transforming Locally 11

Transforming XML Data to XML 14Atom and RSS Elements 14Developing the Stylesheet 17

Summary 23

Chapter 2: Introducing XPath 25

Nodes 25Node Types 26Node Properties 26

Data Model 27Path Expressions 28

Using an XPath Analyzer 29Axes 30Node Tests 32Predicates 33Operators 33

XPath Functions 35Strings 35Dates, Times, and Durations 37Nodes and Documents 38Numbers 39

Summary 40Exercises 40

Chapter 3: Templates, Variables, and Parameters 43

About Templates 44Template Rules 44

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Contents

Invoking a Rule 45Using Modes 46Setting Priorities 48Built-in Rules 49

Named Templates 49Variables 50Parameters 55

Global Parameters 55Template Parameters 57

Summary 59Exercises 60

Chapter 4: Using Logic 61

Conditional Processing 61A Simple Choice 61Multiple Choices 62Using XPath for Conditional Tests 64

Iteration 64Using Attribute Sets 64Monitoring the Context 69

Processing XML Code 70Summary 71Exercises 72

Chapter 5: Sorting and Grouping 75

Sorting Content 75Perform a Sort 81

Grouping 83Common Values 84Adjacent Items 85Starting and Ending Conditions 91

Summary 93Exercises 93

Chapter 6: Strings, Numbers, Dates, and Times 95

String Processing 95About Collations 95General Functions 96Codepoints 96Comparison 97

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Contents

Concatenation 97Simple Substrings 98Using Regular Expressions 99Normalizing Values 101Escaping URIs 102

Numbers 103Generating Numbers 103Formatting Source Numbers 107

Dates and Times 109Contextual Dates 109Formatting 109Combining and Converting Values 111Durations 112Time Zones 112

Summary 113Exercises 114

Chapter 7: Multiple Documents 115

Modular Stylesheets 115Including Modules 116Imported Stylesheets 119

Source Documents 123Using the document() Function 123XPath Alternatives 125Setting or Changing Context 127

Output Documents 127Preparing a Feed Update 129Splitting a Document 136

Summary 138Exercises 139

Chapter 8: Processing Text 141

Controlling Whitespace 141Stripping Space 142Preserving Space 143Using <xsl:text> 143

XML to Text 144Text to XML 146

Loading Unparsed Text 146Analyzing the Input 146

ix

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Contents

Alternatives to XSLT 153XML Maps 154XML Data in Excel 156

Summary 157Exercises 158

Chapter 9: Identifiers and Keys 159

ID Datatypes 159Using the id() Function 160Keys 162

The key() Function 163Generating Identifiers 165

Indexing Lines 165Census to GEDCOM XML 170

Summary 179Exercises 180

Chapter 10: Debugging, Validation, and Documentation 181

Debugging XSLT 181Profiling 184Verifying XHTML Output 185Using Messages 186Commenting Output 187Using the error() Function 188

Type and Schema Validation 188Types in XSLT 188Using a Schema-Aware Processor 189

Documenting Your Stylesheets 195Summary 199Exercises 200

Chapter 11: A Case Study 201

Schema Overview 201Common Elements and Attributes 202

Common Attributes 202Block Elements 202Inline Elements 203

The Quick-Reference Schema 204Link Container Elements 205

x

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Contents

Property Elements 206Link Verification 208

Metadata Schemas 209Resource Metadata 210Subject Metadata 214

Reference Stylesheets 217Link Module 220

Link Parameters 220Function Module 223

Term Module 223Term Parameters 225Displaying Inline Terms 226

Building the Site 227Generating the Reference Pages 228Landing and Glossary Pages 233Creating a Sitemap 234

Summary 237

Appendix A: Answers to Exercises 239

Chapter 1 239Chapter 2 239

Question 1 239Question 2 240Question 3 240

Chapter 3 241Question 1 241Question 2 242

Chapter 4 242Question 1 243Question 2 243

Chapter 5 244Question 1 244Question 2 245Question 3 245

Chapter 6 246Question 1 246Question 2 246Question 3 247

Chapter 7 247Question 1 247

xi

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Contents

Question 2 248Question 3 248Question 4 248

Chapter 8 249Question 1 249Question 2 249Question 3 250

Chapter 9 250Question 1 250Question 2 250Question 3 251

Chapter 10 251Question 1 251Question 2 251

Chapter 11 252

Appendix B: Extending XSLT 253

Stylesheet Functions 253Calling an Extension Function 254

Function Libraries 255EXSLT 255FunctX 256

Vendor Extensions 256User-Defined Extensions 257

Appendix C: XSLT Processing Model 259

The Data Model 259Transforming 260

Parsing Inputs 260Template Rules 261Variables and Parameters 261Controlling Processing 261Outputs and Serialization 262

Appendix D: XSLT 2.0 Quick Reference 263

Elements 263Attribute Groups 264Types 264Functions 264

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Contents

XSLT Elements 264xsl:analyze-string 264xsl:apply-imports 265xsl:apply-templates 265xsl:attribute 266xsl:attribute-set 267xsl:call-template 268xsl:character-map 269xsl:choose 269xsl:comment 270xsl:copy 271xsl:copy-of 271xsl:decimal-format 272xsl:declaration 274xsl:document 274xsl:element 274xsl:fallback 275xsl:for-each 276xsl:for-each-group 276xsl:function 277xsl:if 278xsl:import 279xsl:import-schema 280xsl:include 281xsl:instruction 281xsl:key 282xsl:matching-substring 283xsl:message 283xsl:namespace 284xsl:namespace-alias 285xsl:next-match 285xsl:non-matching-substring 286xsl:number 286xsl:otherwise 288xsl:output 288xsl:output-character 291xsl:param 291xsl:perform-sort 292xsl:preserve-space 293xsl:processing-instruction 294xsl:result-document 294

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