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Rails Modeling Guide#2: Naming Convention for Ruby on Rails Model Methods

Naming conventions play an important role to the software’s overall architecture. It is not a rocket science, still, it may lead to unhappy consequences if not taken care of at the early stage of a project. This small best practices can make a code base significantly improved.

Rails does a good job by using the dynamic power of ruby and providing with a handful of dynamic methods with the models. ActiveRecord::Base and its included modules follow a consistent naming, which clearly represent the intended purpose of the methods. At Code71, we are working on ScrumPad, a 2nd generation agile scrum tool using ruby on rails and our model methods are named according to the following rules-

1. All boolean returning methods end with ‘?’

company.billable?, sprint.current?, story.in_progress?

2. Boolean methods do not start with is_ or has_ or did_ (as you might see in other popular languages)

company.is_billable? -> company.billable?
sprint.is_current? -> sprint.current?

3. find_ and find_all are used only for class (self.find or self.find_all) methods and should return a single/array of object of the class respectively.

find_* methods may return a single object of the class/nil

find_all_* methods return an array of objects of the class or [], but never a nil

4. No methods start with a get_ as other languages.

5. A method ends with ! if it alters the object itself.

sprint.close!()
story.progress!()

6. Methods that persists an object/may throw exception, should always end with ! (implied from rule 5)

invoice.update_status!(:paid)

7. Always use parentheses ‘()’ in method names. Future versions of ruby is deprecating the support for method names without parentheses.

Following these 7 simple rules we have consistent and intuitive model method names across the whole ScrumPad. Let me know if you have any suggestion to these names to make it even better.

Comments

Sohan
@Ashif, thanks!
Ashif Manjur
Thanks for these great tips. Sometimes only following the naming convention can save us a lot of time and effort to understand codes written by others. Keep posting such tips and tricks of beautiful coding.