Book Image

Grails 1.1 Web Application Development

By : Jon Dickinson
Book Image

Grails 1.1 Web Application Development

By: Jon Dickinson

Overview of this book

Web development is trickyóeven a simple web application has a number of context changes ready to trip up the unwary. Grails takes the everyday pain out of web application development, allowing us to focus on delivering real application logic and create seamless experiences that will address the needs of our users. This book will take the pain out of Grails by showing you exactly how to build a web application with a minimum of fuss. With this book, even if you are new to Grails, you will be up and running before you know it. You will be able to code faster and your code will be better. This clear and concise book is packed with examples and clear instructions to help you build your first Grails application and gives you the skills to speed up your application development by adding a different angle for learning about the topic. After a brief introduction to the dynamic JVM-based Groovy programming language, which teaches you enough about Groovy to understand the relationship between Grails and the Groovy scripting language, it shows how to use Grails and a number of key plug-ins to deliver valuable web applications. It also takes you through creating, developing, testing, and deploying an example team collaboration application in Grails. Using an incremental and iterative approach you will learn how to build a basic web application with secure authentication and different levels of authorization. You will learn how to handle file upload allowing users to share files. Some advanced features of object-oriented persistence will be introduced through adding tags for messages and files to giving users a robust categorization system. You will then build on the basic application to enhance the user experience through AJAX and the RichUI plug-in. You will take a further step into the world of Web 2.0 by adding an RSS feed and a REST service to the application. Once the entire application is up and running, you will learn how to create your own plug-in for tagging. Finally, you will learn how to deploy this application to a production environment.
Table of Contents (20 chapters)
Grails 1.1 Web Application Development
Credits
About the author
Acknowledgement
About the reviewers
Preface

RSS


Having addressed the issue of old content being hard to find, we need to add a mechanism to allow users to keep track of all the new content being added to the site. A very simple way to allow this is to create an RSS feed that users can subscribe to if they want. We saw in the last chapter how to return XML from a controller. We can reuse this approach to quickly create a simple RSS feed for the application.

There is a Grails plug-in to help with writing feeds for Grails applications. This is called the Feeds plug-in (http://grails.org/plugin/feeds) and it is built on the ROME API (https://rome.dev.java.net/). Our feed is very simple. Therefore, we can use this as an opportunity to become more familiar with Groovy builders, rather than installing another plug-in.

A note about builders

Whenever producing anything but the simplest XML structure, we must be sure to build the XML in a separate class to the controller class. There are two reasons for this:

  • Good design — encapsulating the...