LoadError: Could not load the 'listen' gem (Rails 5)

Question

I\'ve got an API mode Rails 5 app that won\'t let me run rake routes or rails s. The error I get is:

$ rake routes
rake aborted!
Lo         


        

Answer 1

I had similar problem today after upgrade from Rails 5.1.5 to 5.2.0. First time running the server there was the following 'missing assets' problem:

ActionView::Template::Error (The asset "asterisk_orange.png" is not present in the asset pipeline.)

Trying to precompile the assets shows the 'gem listen error':

$ bundle exec rake assets:precompile
rake aborted!
LoadError: Could not load the 'listen' gem. Add `gem 'listen'` to the development group of your Gemfile

My solution was to explicit set production environment:

$ RAILS_ENV=production bundle exec rake assets:precompile

This precompiles the assets w/o problems and the 'missing assets' problem was fixed.

Answer 2

You might by mistake have set bundle install --without at some point, I sure did anyways.

To revert this run:

bundle config --delete without

I also ran bundle config --delete with as I manually set with option as well by mistake. Running both should get you back to default behaviour.

After having deleted the without config I could successfully run a bundle install again and afterwards my rails s, rails db:migrate etc. worked.

---

You can confirm if this is your issue by running bundle install and look at the second last line in the output. If it states:

Gems in the groups development and test were not installed.

It's for sure above solution should work for you.

Answer 3

I found an easy fix after a lot of trials of rebuild's

bundle config --delete without
bundle config --delete with
bundle install

If you accidentally built the gemset prior to seting your envirnoment correctly, then this may help clear out the problems.

Answer 4

I had same error when trying to generate mongoid database file.

but I created rails new project on ruby 2.5.1. Your ruby is 2.2. so the causality could be different in my situtation.

when I used rails new project, it was created in version 5.2, then I changed gem to 5.1.2 and problem arises. When I created with rails _5.1.6_ new in Gemfile there is generated additional pack for development.

  group :development do
      # Access an IRB console on exception pages or by using <%= console %> anywhere in the code.
      gem 'web-console', '>= 3.3.0'
      gem 'listen', '>= 3.0.5', '< 3.2'
      # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
      gem 'spring'
      gem 'spring-watcher-listen', '~> 2.0.0'
    end

this way 'listen' showed me in gemfile automaticaly