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Writing CGI Applications with Perl
The problem, of course, with most Perl CGI books is that they are written by people who just don't know very much Perl. That's certainly not the case here. Both Kevin and Brent are well-respected members of the Perl community and they know what they are talking about when it comes to writing CGI programs in Perl.
Another common mistake in Perl CGI books is that the authors try to take people who know a bit of HTML and teach them programming, Perl and CGI all at the same time. The authors of this book realise that this approach is likely to lead to, at best, patchy understanding of any of these concepts so they aim there book at people who are already programmers and who have some knowledge of Perl. This means that they can concentrate of teaching the parts of Perl that are useful when writing CGI programs.
One corner that is often cut when discussing CGI programming is security. This is a very dangerous approach to take as a badly written CGI program can leave your web server open to attack from anyone on the Internet. That's not a mistake that is made here as the authors introduce security in chapter 2. Add to that the fact that the code examples all use -w, use strict and CGI.pm and the book is already head and shoulders above most of its competition.
Early chapters look at common CGI requirements such as file uploads and cookies. Each chapter is full of well written (and well-explained) sample code. The example of an access counter in chapter 6 even locks the file containing the current count - this is possibly a first in a Perl CGI book!
By the middle of the book we have already moved beyond simple CGI programming and are looking at mod_perl. This chapter covers both the "faux-CGI" Apache::Registry module and also writing complete mod_perl handlers.
In the second half of the book we start to look at some bigger examples. The authors present a web-based email system and even a shopping cart. In order to fit these examples into their respective chapters a couple of corners have been cut, but there's enough information there to enable anyone to write the complete systems.
Chapter 13 introduces the HTML::Mason module as a way to separate content from presentation. It's obvious that the author's are big fans of this module and this leads to my only real criticism of the book. At no point do they mention the fact that the same benefits can be gained from using any of half a dozen templating systems found on the CPAN. I would have been a lot happier if they had mentioned things like Text::Template, HTML::Template and the Template Toolkit before picking HTML::Mason as the system for their example.
There are then two more long chapters with examples of a document-management system and image-manipulation software. Once more, the code in these examples would serve as a great starting point for anyone wanting to implement something along these lines. The last chapter looks at XML and, in particular, the use of RSS files to provide data feeds to other web sites.
All in all this is a very useful book for someone wanting to write web-based applications using Perl. It's packed full of good advice and code that follows all of the best practices for writing CGI programs in Perl. This book won't teach you Perl, but if you've read Learning Perl or Elements of Programming with Perl then you'll find this book easy enough to follow.
You can purchase Writing CGI Applications with Perl from bn.com. Slashdot welcomes readers' book reviews -- to submit yours, read the book review guidelines, then hit the submission page.
This is a little late in the game for a book that discusses ways to fork off a separate process for each hit on your dynamic pages. I'm sure the authors are studs and all, but if you're programming web applications in Perl, how about using mod_perl, and if you're going to do that, why not bite the bullet and buy Lincoln Stein and Doug Eachern's book from O'Reilly? It is a classic.
Speaking of classics, the old "Writing Web Clients with Perl" is being superseded this month by Sean Burke's "Perl and LWP". Now speaking of Perl studs, they don't get much studlier than Sean, and LWP is (IMHO) the Killer App for Perl programmers. Another fine O'Reilly title (too bad "fine O'Reilly title" is not redundant anymore).
Also from O'Reilly (yawn) is Rasmus Lerdorf's "Programming PHP". I was *very* pleasantly surprised by his book, it is MUCH better than it has any right to be, discussing everything from PEAR DB abstraction classes to speeding up your site with a Squid reverse cache and profiling.
Anyways, that's just my shelf's worth. I use Perl and PHP every day (or at least every day I wear my programmer hat) to get things done fast. I know other people prefer Python and Ruby, hey, more power to them. But I figured I would point out some Fine O'Reilly Titles (note, once again, that phrase is now said more like "Honest Senator" rather than "Stupid Microsoft Security Hole") which have made me some money lately.
YMMV...
Remember that what's inside of you doesn't matter because nobody can see it.
The key is that you can easily run CGI scripts - quite possibly unmodified - with mod_perl thanks to the wonders of the Apache::Registry module that ships with mod_perl. It's all covered in the guide.
-- Sorry, I can't think of anything funny to say here.
- It looks like a nice thick book, but it's very padded. The font is huge (12 to 14 points), there's a lot of padding
(most code samples listed twice, 40 pages of appendix material that could have
been 8 URLs), the margins are huge, and there's an awful lot of repetition (the
10 lines justifying -wT are repeated nearly every time it's used in a program). I bet that the Mouse book squeezes twice as much
content into 450 pages as this one does in 525.
- Some chapters belong better in a Perl book ("Tied Variables").
- Some inclusions/exclusions and focus choices are very odd. There's a very
detailed chapter for Mason, but no mention of templates (literally - not even in
the index).
- Their style is very choppy. They'll present a couple lines of code, then a
paragraph talking about it, repeat. It's very difficult to get a cohesive view
of the program this way - it's spoon-fed to you rather than presented whole. (Undoubtedly this is why they repeat all the code at the end of each chapter, but I prefer longer chunks of unbroken code).
In short, the book is much more vocational than educational. I think this was a conscious decision of theirs, and as such I can hardly fault it - they know their target audience better than I do. However, I've not opened this book once since I read it (cover-to-cover), while I still refer to the Mouse weekly.Need to hack up some code fast? This book will help. If you really want to learn CGI, to know why and how it works, to have a broader grounding in the technologies used with it, and to build a firm foundation for future self-teaching, then IMHO nothing beats the Mouse book.
This isn't as much "normalization" as it is "don't take so many drugs when you're designing tables."
nms is such a place. It has replacements for all of Matt's scripts - and Matt himself has suggested using them as replacements for his buggy versions
I'm sure the author of this review would agree with me that this is a good place to go to get scripts ;-)
-- Sorry, I can't think of anything funny to say here.