uninitialized constant > ActionCable::Server::Configuration::ApplicationCable

Question

When I am running server its throwing error shown in logs below. I googled a lot but didn\'t get reason behind it. Somebody please put some light on it.

Gemfile

Answer 1

According to DHH's video tutorial from yesterday, there's an issue between Spring and an ActionCable dependency, so until the final release of Rails 5 you will need to recreate your project with the --skip-spring option.

Answer 2

I had the same problem when trying to use ActionCable with Rails 4.2.5 and the solution was to add the following to config/application.rb:

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

This is with the ActionCable gem:

gem 'actioncable', github: 'rails/actioncable', branch: 'archive'

Answer 3

The error is related to not having the correct ActionCable files in your project. You need app/channels/application_cable/channel.rb that looks like this

module ApplicationCable
  class Channel < ActionCable::Channel::Base
  end
end

and app/channels/application_cable/connection.rb

module ApplicationCable
  class Connection < ActionCable::Connection::Base
  end
end

Answer 4

If you upgraded from previous version (when actioncable was not in the bundle), check if config/application.rb contains

require "action_cable/engine"