Rails 4: auto load from lib

Question

I'm trying to figure out the auto load thing, but I'm having a hard time making it to work without explicitly requiring the file.

Do I need to make some special configuration so that Rails 4 would be able to auto load files inside lib directory?

If I go to rails console and type $LOAD_PATH I'm able to see that /home/some_user/workspace/rails/myapp/lib is include into load path. This should mean that Rails will be able to auto load correct file?

So as I understand:
if I would place my files inside lib/ directory and I would use the naming conventions, Rails should be able to automatically require the correct file if anywhere in my code I would do something like this:

cats = Cats::SomeCat.new (given that lib/cats/some_cat.rb exists)

and the some_cat.rb contains:

module Cats
    class SomeCat
        def initialize
            @name = "Some cat"
        end
   end
end

However, Rails will show me error uninitialized constant CatController::Cats.

If I add a line require 'cats/some_cat' everything will work. However, in 'The Rails 4 Way' I'm reading that :
The bottom line is that you should rarely need to explicitly load Ruby code in your Rails application (using require) if you follow the naming conventions.

Am I using the wrong naming conventions or am I forced to use that
config.autoload_paths += %W(#{config.root}/lib) thing?

Did you restart the application? It gets initialized only once when the application gets initialized. — nebula, Nov 02 '14 at 16:14
possible duplicate of [Auto-loading lib files in Rails 4](http://stackoverflow.com/questions/19098663/auto-loading-lib-files-in-rails-4) — MZaragoza, Nov 02 '14 at 16:38
As a side note: Subdirectores of `app/` ( and classes/modules therein) will be loaded, that's what I usually do - creating a subdir e.g. `app/workers`. — lllllll, Oct 26 '15 at 17:58

score 3 · Answer 1 · edited Aug 11 '16 at 21:33

3

Add config.autoload_paths += %W(#{config.root}/lib) this code in

config/application.rb

edited Aug 11 '16 at 21:33

Mohit Jain

43,139
57
169
274

answered Oct 11 '15 at 14:52

Sobin Sunny

1,121
10
14

score 0 · Answer 2 · answered Oct 15 '15 at 03:28

You are correct in saying that you need the configuration in your config/application.rb directory.

As mentioned by Sobin, the best way would to include a config.autoload_paths... in that file.

You can find more about this in the rails guides

http://edgeguides.rubyonrails.org/configuring.html

Rails 4: auto load from lib

2 Answers2