The Definitive Guide to Catalyst: Writing Extensible, Scalable, and Maintainable Perl-Based Web Applications

346 Pages·2009·2.18 MB·English

by  Kieren Diment, Matt S Trout, Eden Cardim, Jay Kuri, Jess Robinson (auth.)

The Definitive Guide
to Catalyst
Writing Extensible, Scalable,
and Maintainable Perl-Based
Web Applications
Kieren Diment and Matt S Trout with
Eden Cardim, Jay Kuri, and Jess Robinson
The Definitive Guide to Catalyst: Writing Extensible, Scalable, and Maintainable Perl-Based
Web Applications
Copyright © 2009 by Kieren Diment and Matt S Trout
All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means,
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For Lorna, Freya, and Hunter
Contents at a Glance
Foreword ........................................................................ xv
About the Authors ................................................................xix
About the Technical Reviewer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xxi
Acknowledgments ...............................................................xxiii
Introduction .................................................................... xxv
CHAPTER 1 Introducing the Catalyst Web Application Framework .............1
CHAPTER 2 Catalyst Setup and Background Knowledge .....................19
CHAPTER 3 Your First Catalyst Application ..................................53
CHAPTER 4 Extending LolCatalyst-Lite ......................................81
CHAPTER 5 Deployment ...................................................109
CHAPTER 6 Database Models ..............................................135
CHAPTER 7 The Catalyst Dispatcher .......................................167
CHAPTER 8 Authentication and Authorization ..............................189
CHAPTER 9 Interacting with Web Services in Your Applications .............219
CHAPTER 10 Extending Catalyst ............................................233
CHAPTER 11 Catalyst Cookbook ............................................247
CHAPTER 12 The Reaction Component UI Framework ........................303
APPENDIX A Compiling Your Own Perl ......................................315
APPENDIX B Making Your Own CPAN Mirror
with CPAN::Mini or minicpan.sh ................................317
INDEX .......................................................................319
v
Contents
Foreword ........................................................................ xv
About the Authors ................................................................xix
About the Technical Reviewer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xxi
Acknowledgments ...............................................................xxiii
Introduction .................................................................... xxv
CHAPTER 1 Introducing the Catalyst Web Application Framework ....1
Catalyst’s Usage and History .......................................2
The Model/View/Controller Pattern ..................................2
URL Path Dispatch Logic ......................................6
High-Level Session Management ..............................7
Authentication and Authorization ..............................7
Logging ....................................................7
Templates ..................................................8
Testing .....................................................8
Deployment .................................................8
Catalyst vs. CGI ..................................................9
Introducing Persistence FastCGI ..............................12
mod_perl ..................................................12
Catalyst vs. Other Frameworks ....................................13
URI Routing via External File vs. Self-Contained Controllers ......13
Catalyst vs. CGI::Application ..................................14
Catalyst vs. Jifty ............................................16
Summary .......................................................17
CHAPTER 2 Catalyst Setup and Background Knowledge ..............19
Installing Catalyst ................................................19
Choosing Hardware and Software .............................19
Obtaining Perl ..............................................21
Setting Up CPAN ...........................................23
Installation .................................................24
vii
viii (cid:78)CONTENTS
Catalyst Background Knowledge ..................................24
Hypertext Transfer Protocol ..................................24
Object-Oriented Programming with Moose .....................28
Making the Most of CPAN ........................................44
Search Strategies for CPAN ..................................45
Basic CPAN Usage ..........................................47
Summary .......................................................52
CHAPTER 3 Your First Catalyst Application .............................53
Sample Application Overview .....................................53
Files and Directories .............................................54
Top-Level Directory .........................................54
lib Directory ................................................55
root Directory ..............................................55
script Directory ............................................55
t Directory .................................................56
Getting Started Writing Our Application .............................57
Writing the Application ...........................................59
A Brief Explanation of Views ......................................61
Our First Template ...............................................62
A Brief Introduction to Catalyst Models .............................65
Adding a Different View ..........................................66
Testing .........................................................67
Automated Testing ..........................................69
Fixing the Plan .............................................71
Checking and Fixing the JSON Request ........................72
Adding Authentication for the Web Portion of Our Application ..........74
Adding a New User .........................................75
Requiring Authentication in the Application .........................75
Requiring Authentication for Web Services Requests Only ........75
Requiring Authentication for the Whole Application ..............79
Summary .......................................................79
CHAPTER 4 Extending LolCatalyst-Lite .................................81
First Comes the Model ...........................................82
New Model Capabilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82
Application As Pure UI .......................................82
Measure Twice, Code Once ..................................82
Always Run the First Code from a Test ........................83
(cid:78)CONTENTS ix
Extracting the Model .............................................83
Moving the Model Logic into an Application-Independent Class ...84
Extending the Model .............................................87
A Driver Model for Generic Translation ........................88
Fixing Up the Makefile.PL ....................................89
Enforcing the Interface Using a Role ...........................93
Interlude: LolCatalyst::Lite::Model::SnippetStore ................94
Another Interlude: Spotting Business Logic Errors ...............96
Extending the Application .........................................96
First New Features ..........................................97
A Chained Controller ........................................97
Adding Templates .........................................100
Back to the Test Cycle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101
Interlude: Converting the Snippets to Be Object Based ..........101
Thin Controller, Smart Model .....................................102
Adding Tests for the New View Functionality ..................105
Summary ......................................................108
CHAPTER 5 Deployment .................................................109
Using the Built-in Server ........................................109
Deploying with the Built-in Server ...........................110
HTTP::Prefork Engine Behind a Front-End Proxy ...............111
FastCGI Deployment ............................................117
Deployment on Shared Hosting ..............................118
FastCGI Deployment on Your Own Web Server .................118
Deployment on mod_perl .......................................123
Using Apache As a Back End to a Front-End Proxy .............125
Getting Your Code to the Server ..................................125
Rsync ....................................................125
Version Control Checkout ...................................126
make dist .................................................126
To make install or Not to make install, That Is the Question .....127
Dependency Installation .........................................128
The cpan . Command ......................................130
make installdeps ..........................................131
make catalyst_par .........................................132
Summary ......................................................133
x (cid:78)CONTENTS
CHAPTER 6 Database Models ...........................................135
Choosing and Connecting to a Database ...........................135
Popular Database Systems .................................135
Connecting to the Database from Catalyst ....................136
Designing and Creating the Sample Application Database ...........137
Creating the Catalyst Model ......................................139
Exploring the DBIx::Class Schema Files. . . . . . . . . . . . . . . . . . . . . . . . . . . .141
The Schema File ...........................................141
The Result Files ...........................................142
Deploying to a Different Database System .........................147
Dealing with Data ..............................................149
Simple CRUD ..............................................150
Creating a User ............................................151
Displaying Users ...........................................155
Updating Users ............................................157
Adding Roles ..............................................159
Adding Roles to Users ......................................160
Removing a User ..........................................163
Listing All Users and Their Roles .............................164
Summary ......................................................166
CHAPTER 7 The Catalyst Dispatcher ...................................167
How Catalyst Prepares Before Dispatch ...........................169
The Basic Dispatch Process ......................................169
Two Special Dispatch Types: begin and auto .......................171
LocalRegex and Regex Actions ..............................175
Internal Request Flow Control: $c->forward,
$c->detach, $c->go, and $c->visit ............................177
forward and detach ........................................178
visit and go ...............................................180
The Chained Dispatch Type ......................................181
Overriding the Public Dispatch Paths with Configuration .............187
Summary ......................................................188
(cid:78)CONTENTS xi
CHAPTER 8 Authentication and Authorization ........................189
The Three Parts of Authentication ................................189
Authentication Realms .....................................190
Persistence ...............................................191
Authorization with Roles ....................................192
Installing the Required Modules ..................................193
Catalyst::Plugin::Authentication ..............................193
Catalyst::Authentication::Store::DBIx::Class ...................193
Catalyst::Plugin::Authorization::Roles .........................194
Catalyst::Plugin::Session ....................................194
Our Example Application: SneakyCat ..............................194
Creating and Configuring SneakyCat .........................195
The SimpleDB Option ......................................200
A Side Trip into Application Setup ............................200
Using Authentication .......................................203
Working with Authentication After Login ......................207
Trying Out the Application ..................................209
Adding Finer-Grained Access Control
to SneakyCat with Authorization ..........................211
Working with the Authenticated User .........................216
Summary ......................................................218
CHAPTER 9 Interacting with Web Services in Your Applications .....219
Consuming a Simple REST Service ...............................219
Setting Up OpenCalais in a Catalyst Application ....................220
Creating Web Services with REST ................................224
Implementing the REST Controller ...........................224
Changing the Data Type for Serialization ......................228
Remaining Options for Web Services .........................229
Summary ......................................................231
CHAPTER 10 Extending Catalyst .........................................233
Base Controllers ................................................233
A Simple SerialiseStashKey View .................................234
Action Classes .................................................237
xii (cid:78)CONTENTS
Adding Attributes to Controller Actions ............................237
A Simple Example .........................................238
A More Sophisticated Example ..............................238
Adding More Than One New Attribute ........................240
Cleaning Up Multiple Attributes with Roles ....................241
Extending Catalyst with Plug-ins .................................242
Helper Methods in MyApp.pm ...............................242
Catalyst::Plugin::SmartURI ..................................244
Catalyst::Plugin::Static::Simple ..............................244
Catalyst::Plugin::Server .....................................245
Summary ......................................................245
CHAPTER 11 Catalyst Cookbook .........................................247
Model/View/Controller ...........................................247
Import Existing Schemas to DBIx::Class ......................248
Use DBIx::Class::Tree and Display with JavaScript
and the Template Toolkit .................................249
Catalyst::Model::Factory and Catalyst::Model::
Factory::PerRequest .....................................254
A Way to Quickly Resolve Browser Compatibility Issues .........255
Output CSV from a Controller Action ..........................258
Dynamically Generate Graphics with Catalyst::View::GD ........259
Dynamically Generate Barcodes from Catalyst .................260
Produce Graphs with Chart::Clicker and Catalyst::
View::Graphics::Primitive .................................262
Alternative Templating Systems .............................264
Easy Spam Protection with Catalyst::Controller::reCAPTCHA .....267
Catalyst::View::Component::SubInclude. . . . . . . . . . . . . . . . . . . . . . .269
Handle Legacy CGI Scripts in Catalyst ........................270
Intelligent Use of Base Controllers ...........................272
Catalyst::View::Email::Template .............................275
Miscellaneous Recipes ..........................................277
Run Parts of an Application As a Stand-Alone Script ............277
MojoMojo: The Catalyst Wiki ................................278
Persistent Login and API Authentication ......................281
Multirealm and Progressive Authentication ....................286
Deploy with a Cache .......................................289