When and where do I require files in a rails application?

Question

Let's say I have I have the following file in my lib directory of my rails application:

#lib/proxy.rb module SomeService   class ServiceProxy     def do_something     end   end end 

If I want to use ServiceProxy in a model, I can use it like so:

#app/models/product.rb require 'proxy'  class Product < ActiveRecord::Base   def do_something     proxy = SomeService::ServiceProxy.new     proxy.do_something   end end 

This works, but I noticed if I want to use ServiceProxy in another model, I do not need "require 'proxy'" in the second model file. It seems having "require 'proxy'" once in any model will add it to the lookup path.

Can someone explain this behavior and the best practice surrounding it in a rails app?

Thanks!

UPDATE: Based on floyd's answer below, if my ServiceProxy file was saved as so,

#lib/some_service/service_proxy.rb 

then I would not have to explicitly require the file.

Answer 1

This is a helpful post about this issue.

In short, Rails autoloads classes in your lib directory only if they follow the proper naming conventions.