Rails applications are always fun for the first 2 months. After some time, the initial conventions don't always fit the project. The controllers get fat, the models get fat, and the views gather more logic. How to deal with this complexity? We'll show how to apply typical refactoring recipes to put the code back in order. You'll see examples of service objects and other patterns. All of that using the RubyMine refactoring support, extended with custom shortcuts. The slides from the JetBrains webinar - http://info.jetbrains.com/RubyMine-Webinar-June2015-registration.html

1. Refactoring Rails
apps with RubyMine
Andrzej Krzywda
Arkency

2. Andrzej Krzywda
• Arkency
• Rails since 2004
• hundreds of Rails projects reviewed

3. Agenda
• Typical Rails problems
• Beyond The Rails Way - new patterns
• Refactoring recipes with RubyMine

4. Rails is great
• In the first month of development
• Quick results in almost no code
• Quick feedback loop
• Predictable speed
• Your customer loves you
• You love Rails

5. 2.months.later

6. Typical Rails problems
• MVC is not enough
• first regression bugs
• slow tests
• slower progress

7. 6.months.later

8. Typical Rails problems
• hidden dependencies
• implicit assumptions (aka Convention over
Configuration)
• security bugs!
• Rails upgrades are now projects on their own
with (huge) budgets

9. 2.years.later

10. Typical Rails problems

11. Any questions so far?

12. New guidelines
• explicit > implicit
• reducing meta
• more building blocks

13. New patterns
• Inspired by:
• DDD
• Hexagonal Architecture
• DCI
• CQRS/Event Sourcing

14. The building blocks
• Service objects
• Repositories
• Adapters
• Form objects
• Domain objects
• RubyMine

16. Extract a service object
• the gateway drug
• a training in refactoring
• turn a controller action into a method object

17. Questions?

18. Typical controller coupling
• new-action uses the ‘new’ view
• create-action uses the ‘new’ view
• edit-action uses the ‘new’ view
• ‘new’ view uses _form partial
• ‘edit’ view uses _form partial
• ‘edit’ action uses ‘edit’ view
• ‘update’ action uses ‘edit’ view

19. new
create
edit
update
new.haml
edit.haml
_form.haml
show.rsb
common/error_messages.rsb

20. The filters algebra
• Filters depending on each other
• The order is important
• Hard to decouple
• communication via @ivars

21. At the controllers/views level
everything is communicating
with each other via @ivars

22. Everything is depending
on instance variables

23. Controller instance
variables are the global,
mutable state

24. the Redmine project
• a project management tool
• contains a time-tracking module
• http://www.redmine.org/projects/redmine/wiki/
RedmineTimeTracking
• since 2007
• https://github.com/redmine/redmine

28. RubyMine coding
• look at the existing concerns
• run the subset of tests
• keep refactoring

30. Summary
• Typical Rails problems
• Refactoring example
• RubyMine support

31. • http://rails-refactoring.com/recipes/

32. Fearless
Refactoring: Rails
Controllers
Today 20% off with the
JETBRAINS coupon code!
http://rails-refactoring.com

33. Thank you!
Questions?