Rails 4 uninitialized constant for module

Question

In a new rails 4 app I anm getting an unintialized constant error for a module. The module is named ProcessBill and is located in lib/process_bill.rb

console error:

ActionController::RoutingError (uninitialized constant BillsController::ProcessBill):

controller code:

class BillsController < ApplicationController

  include ProcessBill

lib/process_bill.rb

module ProcessBill

score 78 · Accepted Answer · answered Jun 09 '13 at 08:48

78

Have you added lib to your autoload path? This was necessary in Rails 3, I'm not sure if it's still required for Rails 4.

Try adding this into the class definition in config/application.rb -

    config.autoload_paths += %W(#{config.root}/lib)

answered Jun 09 '13 at 08:48

sevenseacat

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score 44 · Answer 2 · answered May 11 '16 at 05:15

44

I had this problem too with the lib directory with Rails 5 and it appeared in production but not in development. To fix it you need to add the lib directory to eager_load_paths. Here is the relevant part from my application.rb:

config.autoload_paths << "#{Rails.root}/lib"
config.eager_load_paths << "#{Rails.root}/lib"

answered May 11 '16 at 05:15

Peter Marklund

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This article explains why: http://collectiveidea.com/blog/archives/2016/07/22/solutions-to-potential-upgrade-problems-in-rails-5/ – lucke84 Oct 06 '16 at 15:21

Wouter Schoofs · Answer 3 · 2019-09-30T12:07:12.370

8

This will also work in Rails 5 in your application.rb file:

    config.autoload_paths << Rails.root.join('lib')
    config.autoload_paths << Rails.root.join('lib/notifier')

edited Sep 30 '19 at 12:07

answered May 11 '17 at 23:54

Wouter Schoofs

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score 5 · Answer 4 · answered Jun 09 '13 at 08:44

5

Try adding this line to the top of your controller:

require "#{Rails.root}/lib/process_bill.rb"

answered Jun 09 '13 at 08:44

Alyssa Ross

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3

You can also do just "require 'process_bill', as the `lib` directory is already on the load path. – Ryan Bigg Sep 30 '13 at 23:09
7

take care, this kills auto reloading! – reto Jan 15 '14 at 12:51
i was needed to do - "require 'process_bill.rb'" – Ravistm Aug 13 '19 at 17:24

Rails 4 uninitialized constant for module

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