Features is a Drupal module that enables configuration from the database, like content types, views, and contexts, to be packaged into modules called "Features". Features consist of generated code that can be version controlled and deployed between environments. Features allow changes to be managed like code instead of only in the database. When a Feature is enabled, all its dependencies are installed as well. If the Feature is later changed, it becomes overridden and the developer must choose whether to revert or update the code.

1. Features
a better way to package stuff
Rob Knight
NWDUG February 2010

2. About me
‣ Drupal developer since version 4.6
‣ Member of the Drupal Association -
you should be too!
‣ Working in Manchester at PRWD

3. Intro
‣ Features is a Drupal module created
by Development Seed
‣ It enables ‘Features’ to be created
which package CCK types, Views,
Contexts and more
‣ It moves configuration from the
database to code

4. What is a Feature?
‣ A Feature is a special kind of module
‣ Features consist of generated code
‣ Features are created via the admin UI
‣ Features have version numbers

5. How a Drupal installation changes
Version
Level Changes
control?
Core Rarely Yes
Contrib Regularly Yes
Custom code Frequently Maybe
Database Constantly No
Problem: how to manage change
in the database?

6. The difference Features make

7. Example: Packaging
a blog Feature
‣ ‘Blog Post’ content type
‣ Some views
‣ A Context for displaying blocks

8. A content type

9. A simple view

10. A context

11. The resulting blog
Text
Here we can see the blog content type,
the context and the view in action

12. Creating a Feature

13. Creating a Feature

14. Creating a Feature

15. Feature contents

16. Generated code

17. Installing the Feature
When the Feature is enabled, all module
dependencies will be enabled too

18. Changes
If any component of the feature is changed, the
Feature is ‘overridden’. In this case, I’ve
changed a View

19. Viewing a ‘diff’
I can now choose to revert the
changes or update the Feature code

20. Version control
‣ Because Features are code, they can
be managed like source code
‣ Updating a Feature is just like
updating a module

21. Deployment
‣ Features are great for ‘additive’
changes
‣ Not so great for ‘destructive’ changes
‣ Complex changes between Feature
versions are still tricky

22. Feature Servers
‣ Imagine running your own
drupal.org-style module repository
‣ Supports “Available Updates”
monitoring
‣ Powerful integration with drush and
drush make

23. What features doesn’t do
(yet)
‣ Taxonomy
‣ Node content and attachments
‣ Menus
‣ However, alternatives exist and more
modules are integrating with
Features

24. Pitfalls
‣ Many contrib modules as yet
unsupported
‣ Features isn’t magic - it’s just a
system for generating code
‣ Upgrades still need some manual
intervention

25. Questions and Answers

26. Thanks for listening
‣ Features is maintained by Development
Seed and is available at
http://drupal.org/project/features
‣ My site & blog are at
http://robknight.org.uk