3 Catalyst::Manual::Tutorial::Intro - Catalyst Tutorial - Part 1: Introduction
8 This is B<Part 1 of 10> for the Catalyst tutorial.
10 L<Tutorial Overview|Catalyst::Manual::Tutorial>
20 L<Catalyst Basics|Catalyst::Manual::Tutorial::CatalystBasics>
24 L<More Catalyst Basics|Catalyst::Manual::Tutorial::MoreCatalystBasics>
28 L<Basic CRUD|Catalyst::Manual::Tutorial::BasicCRUD>
32 L<Authentication|Catalyst::Manual::Tutorial::Authentication>
36 L<Authorization|Catalyst::Manual::Tutorial::Authorization>
40 L<Debugging|Catalyst::Manual::Tutorial::Debugging>
44 L<Testing|Catalyst::Manual::Tutorial::Testing>
48 L<Advanced CRUD|Catalyst::Manual::Tutorial::AdvancedCRUD>
52 L<Appendices|Catalyst::Manual::Tutorial::Appendices>
59 This tutorial provides a multipart introduction to the Catalyst web
60 framework. It seeks to provide a rapid overview of many of its most
61 commonly used features. The focus is on the real-world best practices
62 required in the construction of nearly all Catalyst applications.
64 Although the primary target of the tutorial is users new to the Catalyst
65 framework, experienced users may wish to review specific sections (for
66 example, how to use DBIC for their model classes, how to add
67 authentication and authorization to an existing application, or form
70 You can obtain the code for all the tutorial examples from the
71 catalyst subversion repository by issuing the command:
73 svn co http://dev.catalyst.perl.org/repos/Catalyst/tags/examples/Tutorial/MyApp/5.7/ CatalystTutorial
75 This will download the current code for each tutorial chapter in the
76 CatalystTutorial directory. Each example application directory has
77 the same name as the tutorial chapter.
79 B<These reference implementations are provided so that when you follow
80 the tutorial, you can use the code from the subversion repository to
81 ensure that your system is set up correctly, and that you have not
82 inadvertently made any typographic errors, or accidentally skipped
83 part of the tutorial.>
85 B<NOTE: You can use any perl-supported OS and environment to run
86 Catalyst.> It should make little or no difference to Catalyst's
87 operation, but this tutorial has been written using Ubuntu 8.10
88 because that represents a quick and easy for most people to try out
89 Catalyst with virtually zero setup time and hassles. See the Catalyst
90 installation section below for more information.
92 If you're reading this manual online, you can download the example
93 program and all the necessary dependencies to your local machine by
94 installing the C<Task::Catalyst::Tutorial> distribution from CPAN:
96 cpan Task::Catalyst::Tutorial
98 This will also test to make sure the dependencies are working. If you
99 have trouble installing these, please ask for help on the #catalyst
100 IRC channel, or the Catalyst mailing list.
102 Subjects covered by the tutorial include:
108 A simple application that lists and adds books.
112 The use of L<DBIx::Class|DBIx::Class> (DBIC) for the model.
116 How to write CRUD (Create, Read, Update, and Delete) operations in
121 Authentication ("auth").
125 Role-based authorization ("authz").
129 Attempts to provide an example showing current (5.7XXX) Catalyst
130 practices. For example, the use of
131 L<Catalyst::Action::RenderView|Catalyst::Action::RenderView>,
132 DBIC, L<Catalyst::Plugin::ConfigLoader|Catalyst::Plugin::ConfigLoader>
133 with C<myapp.conf>, the use of C<lib/MyApp/Controller/Root.pm>
134 vs. C<lib/MyApp.pm>, etc.
138 The use of Template Toolkit (TT).
142 Useful techniques for troubleshooting and debugging Catalyst
147 The use of SQLite as a database (with code also provided for MySQL and
152 The use of L<HTML::FormFu|HTML::FormFu> for automated form processing
157 This tutorial makes the learning process its main priority. For
158 example, the level of comments in the code found here would likely be
159 considered excessive in a "normal project." Because of their contextual
160 value, this tutorial will generally favor inline comments over a
161 separate discussion in the text. It also deliberately tries to
162 demonstrate multiple approaches to various features (in general, you
163 should try to be as consistent as possible with your own production
166 Furthermore, this tutorial tries to minimize the number of controllers,
167 models, TT templates, and database tables. Although this does result in
168 things being a bit contrived at times, the concepts should be applicable
169 to more complex environments. More complete and complicated example
170 applications can be found in the C<examples> area of the Catalyst
171 Subversion repository at
172 L<http://dev.catalyst.perl.org/repos/Catalyst/trunk/examples/>.
174 B<Note:> There are a variety of other introductory materials available
175 through the Catalyst web site and at
176 L<http://dev.catalyst.perl.org/wiki/UserIntroductions> and
177 L<http://dev.catalyst.perl.org/>.
180 =head1 VERSIONS AND CONVENTIONS USED IN THIS TUTORIAL
182 This tutorial was built using the following resources. Please note that
183 you may need to make adjustments for different environments and
190 Ubuntu 8.10 (Intrepid Ibex)
198 Catalyst::Devel v1.07
208 The plugins used in this tutorial all have sufficiently stable APIs that
209 you shouldn't need to worry about versions. However, there could be
210 cases where the tutorial is affected by what version of plugins you
211 use. This tutorial has been tested against the following set of plugins:
217 Catalyst::Plugin::Authentication -- v0.10006
221 Catalyst::Plugin::Authorization::ACL -- v0.08
225 Catalyst::Plugin::Authorization::Roles -- v0.05
229 Catalyst::Plugin::ConfigLoader -- v0.20
233 Catalyst::Plugin::Session -- v0.19
237 Catalyst::Plugin::Session::State::Cookie -- v0.09
241 Catalyst::Plugin::Session::Store::FastMmap -- v0.05
245 Catalyst::Plugin::StackTrace -- v0.08
249 Catalyst::Plugin::Static::Simple -- v0.20
255 B<NOTE:> You can check the versions you have installed with the
258 perl -ME<lt>mod_nameE<gt> -e '"print $E<lt>mod_nameE<gt>::VERSION\n"'
261 perl -MCatalyst::Plugin::StackTrace -e 'print "$Catalyst::Plugin::StackTrace::VERSION\n"'
263 Since the web browser is being used on the same box where Perl and the
264 Catalyst development server is running, the URL of
265 C<http://localhost:3000> will be used (the Catalyst development server
266 defaults to port 3000). If you are running Perl on a different box than
267 where your web browser is located (or using a different port number via
268 the C<-p> I<port_number> option to the development server), then you
269 will need to update the URL you use accordingly.
273 Depending on the web browser you are using, you might need to hit
274 C<Shift+Reload> or C<Ctrl+Reload> to pull a fresh page when testing
275 your application at various points (see
276 L<http://en.wikipedia.org/wiki/Bypass_your_cache> for a comprehensive
277 list of options for each browser). Also, the C<-k> keepalive option
278 to the development server can be necessary with some browsers
279 (especially Internet Explorer).
284 =head1 CATALYST INSTALLATION
286 While the rough edges of Catalyst installation have been a problem in
287 the past, this is now mostly solved. Nonetheless, installing Catalyst
288 can be a little time consuming. Although a compelling strength of
289 Catalyst is that it makes use of many of the modules in the vast
290 repository that is CPAN, this can complicate the installation process.
291 However, there are a growing number of methods that can dramatically
292 ease this undertaking. Of these, the following are likely to be
293 applicable to the largest number of potential new users:
301 Given the popularity of Ubuntu and its ease of use, Ubuntu can be
302 a great way for newcomers to experiment with Catalyst. Because it
303 is a "live CD," you can simply boot from the CD, run a few commands,
304 and you should have a fully functional environment in which to do
305 this tutorial in a matter of minutes.
311 Download Ubuntu 8.10 (aka, Intrepid Ibex) Desktop edition and boot from
312 the CD and/or image file, select your language, and then "Try Ubuntu
313 without any changes to your computer."
317 Open a terminal session (click "Applications" in the upper-left
318 corner, then "Accessories," then "Terminal").
322 Add the 'universe' repositories:
324 sudo gedit /etc/apt/sources.list
326 And remove the comments from the lines under the comments about the
327 'universe' repositories.
334 sudo apt-get install libdbd-sqlite3-perl libcatalyst-perl libcatalyst-modules-perl libconfig-general-perl
336 Accept all of the dependencies. Done.
338 NOTE: If you are low on disk space after the above commands (use C<df />
339 to tell), you can free up some space with
340 C<sudo rm /var/cache/apt/archives/*.deb> (the Live CD uses memory for
341 disk space, so having a decent amount of memory will help). And,
342 while the instructions above mention the Live CD because that makes it
343 easy for people new to Linux, you can obviously also use one of the
344 options to install Ubuntu on your drive.
350 Matt Trout's C<cat-install>
352 Available at L<http://www.shadowcatsystems.co.uk/static/cat-install>,
353 C<cat-install> can be a quick and painless way to get Catalyst up and
354 running. Just download the script from the link above and type C<perl
359 Chris Laco's CatInABox
361 Download the tarball from
362 L<http://handelframework.com/downloads/CatInABox.tar.gz> and unpack it
363 on your machine. Depending on your OS platform, either run C<start.bat>
368 Pre-Built VMWare Images
370 Under the VMWare community program, work is ongoing to develop a number
371 of VMWare images where an entire Catalyst development environment has
372 already been installed, complete with database engines and a full
373 complement of Catalyst plugins.
377 Frank Speiser's Amazon EC2 Catalyst SDK
379 There are currently two flavors of publicly available Amazon Machine
380 Images (AMI) that include all the elements you'd need to begin
381 developing in a fully functional Catalyst environment within minutes.
382 See L<Catalyst::Manual::Installation|Catalyst::Manual::Installation>
387 For additional information and recommendations on Catalyst installation,
389 L<Catalyst::Manual::Installation|Catalyst::Manual::Installation>.
391 B<NOTE:> Step-by-step instructions to replicate the environment on
392 which this tutorial was developed can be found at
393 L<Catalyst::Manual::Installation::CentOS4|Catalyst::Manual::Installation::CentOS4>.
394 Using these instructions, you should be able to build a complete CentOS
395 4.X server with Catalyst and all the plugins required to run this
401 This tutorial will primarily focus on SQLite because of its simplicity
402 of installation and use; however, modifications in the script required
403 to support MySQL and PostgreSQL will be presented in Appendix 2.
405 B<Note:> One of the advantages of the MVC design patterns is that
406 applications become much more database independent. As such, you will
407 notice that only the C<.sql> files used to initialize the database
408 change between database systems: the Catalyst code generally remains the
412 =head1 WHERE TO GET WORKING CODE
414 Each part of the tutorial has complete code available in the main
415 Catalyst Subversion repository (see the note at the beginning of each
416 part for the appropriate svn command to use). Additionally, the final
417 code is available as a ready-to-run tarball at
418 L<http://dev.catalyst.perl.org/repos/Catalyst/trunk/examples/Tutorial/Final_Tarball/MyApp.tgz>.
420 B<NOTE:> You can run the test cases for the final code with the following
423 wget http://dev.catalyst.perl.org/repos/Catalyst/trunk/examples/Tutorial/Final_Tarball/MyApp.tgz
426 CATALYST_DEBUG=0 prove --lib lib t
431 Kennedy Clark, C<hkclark@gmail.com>
433 Please report any errors, issues or suggestions to the author. The
434 most recent version of the Catalyst Tutorial can be found at
435 L<http://dev.catalyst.perl.org/repos/Catalyst/Catalyst-Manual/5.70/trunk/lib/Catalyst/Manual/Tutorial/>.
437 Copyright 2006-2008, Kennedy Clark, under Creative Commons License
438 (L<http://creativecommons.org/licenses/by-sa/3.0/us/>).