Using Rails autoload_path, Unable to autoload constant expected incorrect subfolder

Question

I am using the Monologue Gem and Devise Gem.

I am using config autoload_paths to load my subdirectories which include some presentation models.

Rails 4: organize rails models in sub path without namespacing models?

app/config/application.rb

config.autoload_paths += Dir[Rails.root.join('app', 'models', '{*/}')]

My issue, I believe, stems from when I needed to override the Monologue User model. To do so I created a local file

app/models/monologue/user.rb

class Monologue::User < ActiveRecord::Base
    # code
end

I also have my app's user model at

app/models/user.rb

class User < ActiveRecord::Base
    # code
end

The error that I am recieving is

ruby-2.1.5/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:481:in `load_missing_constant': Unable to autoload constant User, expected /Users/Shared/code/kindrdfood/RecRm/app/models/monologue/user.rb to define it (LoadError)

Alex Alex · Accepted Answer · 2016-04-14T18:33:32

You've included a part of the classes namespace into the autoload path (app/models/monologue).

Just keep the autoloading path as it is. The path app/models is already included. Rails tries to find an appropriate file to include for a given class name if it does not exist yet. Without your modification to the load path, User should autoload app/models/user.rb and Monologue::User should autoload app/models/monologue/user.rb.

What Rails actually does, is calling the underscore method on a your class (respectively its string representation). So on a Rails console, you could do something like this:

>> "Monologue::User".underscore
=> "monologue/user"

>> "User".underscore
=> "user"

Edit:

If you want to add custom load pathes to rails' autoload feature, I'd recommend to not put them inside of a folder which is already included in the list. Maybe something like this:

config.autoload_paths << File.join(config.root, "app/decorators")
config.autoload_paths << File.join(config.root, "app/workers")
config.autoload_paths << File.join(config.root, "lib")

Using Rails autoload_path, Unable to autoload constant expected incorrect subfolder

1 Answers