uninitialized constant Rack::Cors #26

blackjid · 2013-06-06T21:38:31Z

I'm having this issue when running a rails 3.2.12 app, it is running with unicorn on production environment

Here is the unicorn log.

/home/deploy/applications/wecul-api/releases/20130606154224/config/application.rb:72:in `<class:Application>'
:
uninitialized constant Rack::Cors
 (
NameError
)
    from /home/deploy/applications/wecul-api/releases/20130606154224/config/application.rb:12:in `<module:PeepoltvApi>'
    from /home/deploy/applications/wecul-api/releases/20130606154224/config/application.rb:11:in `<top (required)>'
    from /home/deploy/applications/wecul-api/releases/20130606154224/config/environment.rb:2:in `require'
    from /home/deploy/applications/wecul-api/releases/20130606154224/config/environment.rb:2:in `<top (required)>'
    from config.ru:4:in `require'
    from config.ru:4:in `block in <main>'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/builder.rb:51:in `instance_eval'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/builder.rb:51:in `initialize'
    from config.ru:1:in `new'
    from config.ru:1:in `<main>'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn.rb:44:in `eval'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn.rb:44:in `block in builder'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn/http_server.rb:722:in `call'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn/http_server.rb:722:in `build_app!'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn/http_server.rb:140:in `start'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/unicorn-4.6.2/bin/unicorn:126:in `<top (required)>'
    from bin/unicorn:16:in `load'
    from bin/unicorn:16:in `<main>'
E, [2013-06-06T21:20:28.718097 #7506] ERROR -- : reaped #<Process::Status: pid 30554 exit 1> exec()-ed

In my `Gemfile` I've added

gem 'rack-cors', :require => 'rack/cors'

In my `config/application.rb` I've added

config.middleware.use Rack::Cors do
  allow do
    origins '*'
    resource '*', :headers => :any, :methods => [:get, :post, :delete, :put, :options]
  end
end

I'd already tryied

Adding require 'rack/cors' in my `config/application.rb'
I've tryied this in the rails console with this output

Loading production environment (Rails 3.2.12)
irb(main):001:0> Rack::Cors
 => Rack::Cors

The text was updated successfully, but these errors were encountered:

cyu · 2013-06-07T11:32:58Z

What does your Gemfile look like?

blackjid · 2013-06-07T11:46:26Z

Hi @cyu
This is my Gemfile https://github.com/peepoltv/peepoltv-api/blob/master/Gemfile#L12
And this is my config file https://github.com/peepoltv/peepoltv-api/blob/master/config/application.rb

thanks

cyu · 2013-06-07T14:45:53Z

Try replacing the class reference w/ a string:

config.middleware.use "Rack::Cors" do
  allow do
    origins '*'
    resource '*', :headers => :any, :methods => [:get, :post, :delete, :put, :options]
  end
end

cyu · 2014-08-21T22:42:53Z

Closing this issue. Please re-open if you're still having issues.

arcreative · 2014-09-03T19:26:15Z

Having the same issue as OP, using the string doesn't work for me either.

cyu · 2014-09-24T16:52:48Z

@arcreative Are you still having this issue? And you've re-started your app after adding the gem?

cheshire137 · 2014-09-24T17:39:22Z

Having the same issue in a Rails 4 app in production environment.

cyu · 2014-09-26T13:26:42Z

@moneypenny Can you send post the Gemfile and the application.rb (or wherever you're using the middleware)

cheshire137 · 2014-10-08T15:11:55Z

Sorry for the delay. Here's our Gemfile:

source 'https://rubygems.org'

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '4.1.5'

# Use pg as the database for Active Record
gem 'pg', '~> 0.17.1'

# Use SCSS for stylesheets
gem 'sass-rails', '~> 4.0.3'
gem 'bootstrap-sass', '~> 3.1.1'
gem 'font-awesome-sass', '~> 4.1.0'

# Presentation
gem 'haml', '~> 4.0.5'
gem 'haml-rails', '~> 0.5.3'
gem 'jbuilder', '~> 2.0.3'
gem 'liquid', '~> 2.6.1'
gem 'kramdown', '~> 1.4.0'

# For copying text
gem 'zeroclipboard-rails', '~> 0.1.0'

# For diffs
gem 'codemirror-rails', '~> 4.5'

# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'

# Use CoffeeScript for .js.coffee assets and views
gem 'coffee-rails', '~> 4.0.0'

# See https://github.com/sstephenson/execjs#readme for more supported runtimes
# gem 'therubyracer', platforms: :ruby

# Use jquery as the JavaScript library
gem 'jquery-rails', '~> 3.1.1'

# Turbolinks makes following links in your web application faster. Read more: https://github.com/rails/turbolinks
gem 'turbolinks', '~> 2.2.2'
gem 'jquery-turbolinks', '~> 2.0.2'

group :doc do
  # bundle exec rake doc:rails generates the API under doc/api.
  gem 'sdoc', require: false
end

# for configuration
gem 'dotenv-rails', '~> 0.11.1'

# Use ActiveModel has_secure_password
# gem 'bcrypt-ruby', '~> 3.1.2'

# Authentication
gem 'devise', '~> 3.2.2'
gem 'omniauth-oauth2', '~> 1.1.2'

# Authorization
gem 'cancancan', '~> 1.8'

# Background processing
gem 'sidekiq', '~> 3.0.0'

# For exception notification
gem 'airbrake', '~> 4.0.0'

gem 'git', '~> 1.2.7'
gem 'ace-rails-ap', '~> 2.0.1'
gem 'jekyll', '~> 2.1.1'

# For website publishing state
gem 'aasm', '~> 3.3.1'

# Friendly JavaScript editor
gem 'tinymce-rails'

gem 'rake', '~> 10.3.2'

gem 'fog', '~> 1.23.0'

gem 'rack-cors', '~> 0.2.9', require: 'rack/cors'

group :development do
  # Spring speeds up development by keeping your application running in the
  # background. Read more: https://github.com/rails/spring
  gem 'spring'

  gem 'spring-commands-rspec'
  gem 'awesome_print', '~> 1.2.0'
  gem 'pry-rails', '~> 0.3.2'
  gem 'thin', '~> 1.6.2'
  gem 'foreman', '~> 0.74.0'

  gem 'capistrano', '~> 3.2.0'
  gem 'capistrano-rails', '~> 1.1.1'
  gem 'capistrano-bundler', '~> 1.1.2'
  gem 'capistrano-sidekiq', '~> 0.3.3'
end

group :development, :test do
  # Use debugger
  # gem 'debugger'

  gem 'rspec-rails', '~> 3.0.2'
  gem 'rspec-collection_matchers', '~> 1.0.0'
  gem 'factory_girl_rails', '~> 4.4.1'
  gem 'database_cleaner', '< 1.1.0'
  gem 'simplecov', '~> 0.9.0', require: false
  gem 'capybara'
  gem 'capybara-webkit'
end

gem 'unicorn', '~> 4.8.3'

And config/application.rb from the Rails app:

require File.expand_path('../boot', __FILE__)
require 'rails/all'
Bundler.require(:default, Rails.env)
Dotenv.overload('dotenv.test') if Rails.env.test?
module MyApp
  class Application < Rails::Application
    config.middleware.insert_before 'ActionDispatch::Static', 'Rack::Cors' do
      allow do
        origins '*'
        resource '*', headers: :any,
                      methods: [:get, :post, :options, :delete, :head, :put],
                      max_age: 0
      end
    end
    config.generators do |g|
      g.test_framework :rspec
    end
    config.autoload_paths << Rails.root.join('lib')
  end
end

In config/environments/production.rb, we have config.serve_static_assets = true.

cyu · 2014-10-09T11:39:18Z

Everything looks okay... I have a example app (in the examples directory) using Rails 4.1.5 and starts up okay. How about the backtrace? What does that look like?

akinnunen · 2015-05-08T09:21:29Z

Try adding:

require 'rack'
require 'rack/cors'

mcka1n · 2015-05-18T02:37:36Z

+1 @akinnunen It makes sense to add those requires before use Rack::Cors do. It worked for me.

tknazn · 2016-08-05T07:57:26Z

@akinnunen @mcka1n
I encountered the following issue after adding requires into application.rb. Development works but it failed to push to Heroku
Please advise.
LoadError: cannot load such file -- rack/cors

aminukano585 · 2019-01-29T07:23:02Z

I'm having this issue when running a rails 3.2.12 app, it is running with unicorn on production environment

Here is the unicorn log.

/home/deploy/applications/wecul-api/releases/20130606154224/config/application.rb:72:in `<class:Application>'
:
uninitialized constant Rack::Cors
 (
NameError
)
    from /home/deploy/applications/wecul-api/releases/20130606154224/config/application.rb:12:in `<module:PeepoltvApi>'
    from /home/deploy/applications/wecul-api/releases/20130606154224/config/application.rb:11:in `<top (required)>'
    from /home/deploy/applications/wecul-api/releases/20130606154224/config/environment.rb:2:in `require'
    from /home/deploy/applications/wecul-api/releases/20130606154224/config/environment.rb:2:in `<top (required)>'
    from config.ru:4:in `require'
    from config.ru:4:in `block in <main>'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/builder.rb:51:in `instance_eval'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/builder.rb:51:in `initialize'
    from config.ru:1:in `new'
    from config.ru:1:in `<main>'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn.rb:44:in `eval'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn.rb:44:in `block in builder'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn/http_server.rb:722:in `call'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn/http_server.rb:722:in `build_app!'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn/http_server.rb:140:in `start'
    from /home/deploy/applications/wecul-api/shared/bundle/ruby/1.9.1/gems/unicorn-4.6.2/bin/unicorn:126:in `<top (required)>'
    from bin/unicorn:16:in `load'
    from bin/unicorn:16:in `<main>'
E, [2013-06-06T21:20:28.718097 #7506] ERROR -- : reaped #<Process::Status: pid 30554 exit 1> exec()-ed

In my `Gemfile` I've added

gem 'rack-cors', :require => 'rack/cors'

In my `config/application.rb` I've added

config.middleware.use Rack::Cors do
  allow do
    origins '*'
    resource '*', :headers => :any, :methods => [:get, :post, :delete, :put, :options]
  end
end

I'd already tryied

Adding require 'rack/cors' in my `config/application.rb'
I've tryied this in the rails console with this output

Loading production environment (Rails 3.2.12)
irb(main):001:0> Rack::Cors
 => Rack::Cors

Your bug happens to be my solution, odd enough :)

promisepreston · 2019-04-16T20:17:58Z

You just need to un-comment the Rack CORS gem in your Gemfile (gemfile.rb)

# gemfile.rb
gem 'rack-cors'

And then run the code below to install the gem
bundle install

And also ensure that your cors initializer (cors.rb) is set this way
# config/initializers/cors.rb

Rails.application.config.middleware.insert_before 0, Rack::Cors do
  allow do
    origins '*'

    resource '*',
      headers: :any,
      methods: [:get, :post, :put, :patch, :delete, :options, :head]
  end
end

Setting origins to '*' should be alright for development, but keep in mind that if you deploy to production you’ll want to change this value to match your front-end’s URI for security reasons.

Hope this helps

cyu · 2020-05-07T17:43:48Z

I'm closing this issue because there hasn't been any activity on this issue in a while.

JessicaSew · 2021-10-05T16:21:52Z

I'm having an issue when starting up my server with shotgun:
Boot Error
Something went wrong while loading config.ru

LoadError: cannot load such file -- rack/cors

henriqueutsch · 2023-01-24T18:29:12Z

I'm having this issue too and this code resolv for me.

`
app_urls = ENV.fetch('APP_ORIGIN_URL', '').to_s.split(',').compact

if app_urls.present?
require 'rack'
require 'rack/cors'

Rails.application.config.middleware.insert_before 0, Rack::Cors do
allow do
origins *app_urls

  resource '*',
           headers: :any,
           methods: [:get, :post, :put, :patch, :delete, :options, :head]
end

end
end
`

cyu closed this as completed Aug 21, 2014

cyu reopened this Oct 9, 2014

DeeDeeG mentioned this issue Feb 2, 2018

Remove rack-jsonp for rack-cors RefugeRestrooms/refugerestrooms#341

Open

cyu closed this as completed May 7, 2020

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uninitialized constant Rack::Cors #26

uninitialized constant Rack::Cors #26

blackjid commented Jun 6, 2013

cyu commented Jun 7, 2013

blackjid commented Jun 7, 2013

cyu commented Jun 7, 2013

cyu commented Aug 21, 2014

arcreative commented Sep 3, 2014

cyu commented Sep 24, 2014

cheshire137 commented Sep 24, 2014

cyu commented Sep 26, 2014

cheshire137 commented Oct 8, 2014

cyu commented Oct 9, 2014

akinnunen commented May 8, 2015

mcka1n commented May 18, 2015

tknazn commented Aug 5, 2016 •

edited

Loading

aminukano585 commented Jan 29, 2019

Here is the unicorn log.

In my `Gemfile` I've added

In my `config/application.rb` I've added

I'd already tryied

promisepreston commented Apr 16, 2019 •

edited

Loading

cyu commented May 7, 2020

JessicaSew commented Oct 5, 2021

henriqueutsch commented Jan 24, 2023

uninitialized constant Rack::Cors #26

uninitialized constant Rack::Cors #26

Comments

blackjid commented Jun 6, 2013

Here is the unicorn log.

In my Gemfile I've added

In my config/application.rb I've added

I'd already tryied

cyu commented Jun 7, 2013

blackjid commented Jun 7, 2013

cyu commented Jun 7, 2013

cyu commented Aug 21, 2014

arcreative commented Sep 3, 2014

cyu commented Sep 24, 2014

cheshire137 commented Sep 24, 2014

cyu commented Sep 26, 2014

cheshire137 commented Oct 8, 2014

cyu commented Oct 9, 2014

akinnunen commented May 8, 2015

mcka1n commented May 18, 2015

tknazn commented Aug 5, 2016 • edited Loading

aminukano585 commented Jan 29, 2019

Here is the unicorn log.

In my Gemfile I've added

In my config/application.rb I've added

I'd already tryied

promisepreston commented Apr 16, 2019 • edited Loading

cyu commented May 7, 2020

JessicaSew commented Oct 5, 2021

henriqueutsch commented Jan 24, 2023

In my `Gemfile` I've added

In my `config/application.rb` I've added

tknazn commented Aug 5, 2016 •

edited

Loading

In my `Gemfile` I've added

In my `config/application.rb` I've added

promisepreston commented Apr 16, 2019 •

edited

Loading