Grails is an open source web application framework that is built on Groovy and Java. It provides a high productivity environment for building web applications using conventions over configurations and MVC architecture. Some key features include dynamic typing, closures, GORM for object relational mapping, plugins, and easy production deployment. The framework aims to allow developers to focus on business logic rather than infrastructure plumbing.

1. GRAILS
BY
RENAUD HOYOUX

2. ABOUT ME
Lead Developer on Cytomine.
Benevolent Dictator of the non-pro t organization Kodo
Wallonie.
Coach at CoderDojo Liège.

4. CYTOMINE TECHNOLOGIES

5. CYTOMINE IS OPEN MIND
Open Source
Open Science & Open Data & Open Access
Open Education & Open Entrepreneurship

6. WHAT IS GRAILS ?

7. GRAILS
Web application framework
Open Source (Apache 2)
High-Productivity & Flat learning curve
Based on the Java platform (Groovy)
Convention over Con guration
MVC

8. WHAT'S GROOVY ?

9. WHAT'S GROOVY ?
Compiled to JVM
Dynamic langage (with dynamic typing)
Operators overloading
Closures
Useful for scripting
More OO than Java

10. DYNAMIC
def myVariable = "Coucou"
myVariable = myVariable.toCharArray();
myVariable = 42
void test(){
throw new tooMuchPeketException("up");
}
void test2() {
test()
}

11. MAPS ... MAPS EVERYWHERE
def pair = [first : 17, second : "test"]
def developer = [name : Hoyoux, age : 27, language:Groovy]
println pair.first

12. CLOSURES
//empty list
def developers = []
developers << [name : Hoyoux, age : 27, language:Groovy]
developers << [name : Doe, age : 41, language:PHP]
//...
String bestLanguage = "Java"
def ages = developers.findAll{it.language == bestLanguage}
.collect{it.age}

13. MVC ?

14. MVC !

15. CONVENTION OVER CONFIGURATION

16. SIMPLICITY
controllers in grails-app/controllers
domains in grails-app/domain
services in grails-app/services
views in grails-app/views
tests in test
...

17. NO XML

18. DEMO ?

19. NO !

20. Sorry, it was a video here.
CREATE AN APP

21. Sorry, it was a video here.
CREATE A DOMAIN

22. Sorry, it was a video here.
CREATE A CONTROLLER

23. Sorry, it was a video here.
THEN THE VIEW

24. DYNAMIC FINDERS IN GORM
Talk.findByTitle("Grails is awesome")
Talk.findAllBySubtitle("I want sandwiches")
Talk.findAllBySpeakerAndDateBetween(speaker, firstDate, secondDate)

25. PLUGINS

26. AND SO ON
Filters
Internationalization
Web Flows

27. PRODUCTION
grails war
Generate a classical war to deploy like a Java war.
George Orwell
“All Web ARchives are equal ...”

28. HIGH PRODUCTIVITY
FOCUSING ON BUSINESS INSTEAD OF PLUMBING

30. CONCLUSION
Grails is cool.
Grails is not an opponent of JavaEE.
The competitor frameworks are Ruby on Rails or Django.

31. @TheGeekTortoise