Customer Reviews

XML and Perl

5 star:		(6)
4 star:		(6)
3 star:		(0)
2 star:		(0)
1 star:		(1)

 

 

One of Perl's great strengths is in processing text files. That is, after all, why it became so popular for generating dynamic web pages - web pages are just text (albeit text that is supposed to follow particular rules). As XML is just another text format, it follows that Perl will be just as good at processing XML documents. It's therefore surprising that using Perl for XML processing hasn't recieved much attention until recently. That's not saying that there hasn't been work going on in that area - many of the Perl XML processing modules have long and honourable histories - it'd just that the world outside of the Perl community doesn't seem to have taken much notice of this work. This is all set to change with the publication of this book and O'Reilly's Perl and XML.

XML and Perl is written by two well-known members of the Perl XML community. Both are frequent contributors to the "perl-xml" mailing list, so there's certainly no doubt that they know what they are talking about. Which is always a good thing in a technical book.

The book is made up of five sections. The first section has a couple of chapters which introduce you to the concepts voered in the book. Chapter one introduces you separately to XML and Perl and then chapter two takes a first look at how you can use Perl to process XML. This chapter finishes with two example programs for parsing simple XML documents.

Section two goes into a lot more detail about parsing XML documents with Perl. Chapter three looks at event-driven parsing using XML::Parser and XML::Parser::PerlSAX to demonstrate to build example programs before going to talk in some detail about XML::SAX which is currently the state of the art in event-driven XML parsing in Perl. It also looks at XML::Xerces which is a Perl inteface to the Apache Software Foundation's Xerces parser. Chapter four covers tree based XML parsing and presents examples using XML::Simple, XML::Twig, XML::DOM and XML::LibXML. In both of these chapters the pros and cons of each of the modules are discussed in detail so that you can easily decide which solution to use in any given situation.

Section three covers generating XML documents. In chapter five we look at generating XML from text sources using simple print statements and also the modules XML::Writer and XML::Handler::YAWriter. Chapter six looks at taking data from a database and turning that into XML using modules like XML::Generator::DBI and XML::DBMS. Chapter seven looks at miscellaneous other input formats and contains examples using XML::SAXDriver::CSV and XML::SAXDriver::Excel.

Section four covers more advanced topics. Chapter eight is about XML transformations and filtering. This chapter covers using XSLT to transform XML documents. It covers the modules XML::LibXSLT, XML::Sabletron and XML::XPath.

Chapter nine goes into detail about Matt Sergeant's AxKit, the Apache XML Kit which allows you to create a website in XML and automatically deliver it to your visitors in the correct format.

Chapter rounds off the book with a look at using Perl to create web services. It looks at the two most common modules for creating web services in Perl - XML::RPC and SOAP::Lite.

Finally, section five contains the appendices which provide more background on the introductions to XML and Perl from chapter one.

There was one small point that I found a little annoying when reading the book. Each example was accompanied with a sample of the XML documents to be processed together with both a DTD and an XML Schema definition for the document. This seemed to me to be overkill. Did we really need both DTDs and XML Schemas for every example. I would have found it less distracting if one (or even both) of these had been moved to an appendix.

That small complaint aside, I found it a useful and interesting book. It will be very useful to Perl programmers (like myself) who will increasingly be expected to process (and provide) data in XML formats.

This book surveys two dozen of the more important XML modules
available for Perl. It is aimed at the intermediate-level Perl
developer who has little exposure to XML and wants to know what the
fuss is all about, or who just needs a roadmap to find his/her way
amongst the hundred-odd Perl modules available on CPAN.

I found the book generally acceptable as computer books go. The
layout of the book is useful and visually pleasing, the section
headers are descriptive rather than cutesy or humorous, and the
authors write seriously and stick to the topic. The program examples
are to the point, and the authors have made a clear effort to come
up with plausible problems to solve rather than using completely
contrived examples. The example XML documents all have DTDs and
Schemas to define their format, which is good practice and refreshing
to see.

The range of topics is good, covering less obvious topics like SOAP
and web delivery of XML documents with AxKit, as well as the expected
discussions of parsing via SAX and DOM.

The faults of the book are twofold. The first problem is the need
for another round of editing. The program listings are almost all fine
(but beware the typo in p. 166, line 24 in the listing) yet the text
is sometimes repetitive and could use another round of tightening up.
Yes, this is true of almost every computer book, but hope springs eternal....

More disappointing to me was the second problem, which is inconsistent
focus. It's in the nature of a survey book to prefer breadth to
depth, but still I found the authors choices on what to discuss and
what to ignore were sometimes curious. I learned that there are SAX1
and SAX2 standards, but not what the difference is between them, nor
when I should prefer one to the other, nor what improvement they offer
over XML::Parser. There is a three-page discussion (p.155-158) of the
entirely-obvious production of XML documents with "print"
statements but no mention at all of XML encoding schemes and how they can
bite you in Perl 5.6.

My spot check of the index was an unhappy experience (the index won't
tell you that the document validation features of XML::Xerces are
mentioned on p.100) and the URL for the book's errata (p.xviii) gives
a 404 error as of this writing.

I'm an experienced Perl programmer with a little XML already under my
belt, so the book was helpful to me in giving me an overview of my
options for my next Perl/XML app. It's not in the Camel book's class,
but it is useful for the intended audience.

I am just beggining to program with Xml and Perl, and I found this book helpful, very helpful. This book was very clear, I had no problems reading it. I learned to do things with this book that no other perl or xml book taught me. Very Informative, but at the same time not too long to read.

The authors of this book, definitely know the subject. I believe one of them is an author of quite a few XML modules, though both are widely known in the Perl XML community.

This book definitely covers the state of Perl and XML. It goes over the most important modules, in great detail and providing concrete examples. I especially like the first two chapters, which in detail get you prepared for the rest of the book. The coverage of XML parsing theory was a great topic to cover. Two large chapters, each dedicated to SAX and DOM respectively, covered both parsing technologies in great detail.

Many, many, more great chapters. Apart from some typos, which are inevitable in any book, this book stands way above the O'Reilly counterpart, which I also own.

_XML and Perl_ provides a welcome overview and guided tour of the dozens of XML related Perl modules. When I first looked at manipulating XML with Perl, I was overwhelmed by the kaleidoscope of options. Trying to make sense of the individual modules and how they fit together was a frustrating experience, and ultimately I gave up. This time around, I appreciate Riehl & Sterin providing a variety of guidance in the form of Appendices, an Acronym list, chapter overviews, multiple examples, and chapter exercises. When presenting a subject, they explain the tradeoffs with various approaches and compare the benefits of each. There are a few distracting typo's, however nothing which should throw anyone off-track. Overall _XML and Perl_ has given me a much needed roadmap while introducing two-dozen of the XML related Perl modules.

A really good overview of the 'state of the art' in the XML/Perl world.

Things I like most about this book :

the content is structured and clear to follow

the didactic style provides 'real-world' examples with explanations, which can easily be modified and extended

It is so succinct it can be read in a weekend. Both highly readable and informative.

I hate to admit it, but I have not felt the need to buy the O'Reilly Perl & XML book yet.

(Keep up the good work New Riders)

XML has been the monster in my closet for years now. Perl has been my teddy bear. I had the pleasure of opening the closet door with my teddy bear held tightly in my arms to protect me.

This book is an excellent way to bring the power of the two strongest tools in use today together. Having the XML quick reference in the back helps to guide a new XML user through the concepts. This book is a must read for perl programmers looking to expand their skills into XML.

This book covers the main XML Perl modules and provides good starting point for working with XML in Perl. The book includes coverage of modules used for XML generation and XML parsing (both tree-based and event-based). It also provides coverage of advanced topics, ...as AxXit and Web Services using SOAP. Personally I found the chapter on event-based parsing to
be the most useful. Although the SAX examples are fairly simple, I was able to successfully convert some of my own
code from XML tree-based to XML event-based parsing which provided a significant performance improvment.

The only downside I found with the book is that it needs another round of editing, information is repeated, sometimes
the repeated information is within one or two pages of each other, which I found annoying.

I would recommend this book to anyone who is new to working with XML and Perl.

If you are interested in this book, you should already be aware of the importance of XML. Perhaps you already have used it elsewhere. More importantly, you should already have the basics of Perl. The book does not start from scratch on it. Though it assumes no prior knowledge of XML. It shows what can be done in Perl, to parse, change and write XML. Numerous modules already exist, especially for parsing. You really do not want to write an XML parser!

Once you've understood enough to have your own custom XML files and be able to write Perl to read and display these, then it should get easier. Those initial steps can then easily be modified as your XML data and analysis changes.

The introduction tells you exactly what you're going to get and then you get it. The chapters follow a logical and intuitive structure with plenty of helpful graphics and code samples. I would have liked to have seen more about the differences between XSLT and CSS and why I should use one over the other. A great job is done explaining the differences between DTDs and XML Schemas, advantages and disadvantages of each, who should use which approach and why. The section on using XML with RDBMS was especially helpful. Overall, this is an excellent book. I'd recommend it to any intermediate Perl hacker or XML type. For beginners, I'd recommend "Learning Perl" (O'Reilly) and "XML for Dummies" (IDG), then this book.