It contains rails engine basics, and answers of some wh question regarding rails engine

1. Rails Engine
An awesome tool to extend your rails application
Muntasim Ahmed
Platform Architect @ Tasawr Interactive
https://github.com/railscash
muntasim@tasawr.com

2. Agenda
• Why Rails Engine
• What is Rails Engine
• How it works with Rails Core
• Who are they
• Where is your interest

3. Problems
• Large application without reusable component
• Slow testing ( if any :) )
• Larger app, messy

4. Solution
• Find common functionalities
• Extract them to module => Gems
• Use railtie to tie with Rails App => Rails Engine

5. One Thing!
Rails (version>=3.1) is just a “supercharged” engine
http://edgeguides.rubyonrails.org/engines.html

6. Rails Engine ?
• pre-packaged application
• able to be run or mounted within another Rails
application
• can have its own models, views, controllers,
generators and publicly served static files

7. Rails Engine ?
•

8. Rails Engine has
Image source: Railscasts.com

9. Rails Engine has
Image source: Google

10. Rails Engine has
Image source: Google

11. Rails Engine has
Image source: Google

12. Rails engine walk-through
• Create an engine
• Implement requirements in app, lib etc.
• Test
• Mount to main app
• Override where necessary
• And done!

13. Rails engine walk-through
Create
rails plugin new awesome_engine --mountable
Then generate mvc stuffs, test
In App Gemfile
gem "awesome_engine", path => "awesome_engine_path
In App Route
mount AwesomeEngine::Engine => "/awesome_engine_path", as =>
“awesome_engine"

14. Rails engine walk-through
Hit localhost:3000/awesome_engine_path
(mount point)
It will hit engine's root path
Welcome to awesome engine
home!

15. Rails engine walk-through
Routes:
Use engine routes from main app using
engine_name.route_name
e.g. awesome_name.root_path

16. Rails engine walk-through
Routes:
Use main app routes from engine using
main_app.route_name
e.g. main_app.root_path

17. Who are they
• Rails Admin
• Devise
• Blogit
• Tolk
• .....

18. References
• http://railscasts.com/episodes/277-mountable-engines
• http://www.slideshare.net/AndyMaleh/rails-engine-patterns
• http://www.slideshare.net/mirrec/rails-engine-rubyslava
• http://edgeguides.rubyonrails.org/engines.html
• http://edgeapi.rubyonrails.org/classes/Rails/Engine.html
• http://pivotallabs.com/users/shagemann/blog/articles/1994-
migrating-rom-a-single-rails-app-to-a-suite-of-rails-engines
Image source:
Google, Railscasts and Dulal Khan

19. Thanks for your attention :)

20. ???
Question(s)