cloud9 - Upgraded Rails to 6, getting Blocked host Error

Question

I needed the new function in ActiveStorage to resize_to_fill so I upgraded to Ruby 2.5.1 and Rails 6.

ruby '2.5.1'

gem "rails", github: "rails/rails"

When I stopped, then started my server (Cloud 9), I received the Rails error:

Blocked host: xxxxxxx-xxxxxxx.c9users.io To allow requests to xxxxxxx-xxxxxxx.c9users.io, add the following configuration:

Rails.application.config.hosts << "xxxxxxx-xxxxxxx.c9users.io"

I've tried restarting, new windows, but nothing gets rid of this. I've never seen this error before. I'm guessing the new version of Rails is doing something?

question from:https://stackoverflow.com/questions/53878453/upgraded-rails-to-6-getting-blocked-host-error

Answer 1

The Blocked Host is a new feature of Rails 6. You can add this pattern to your config/environments/development.rb to have no worries of that in case of dynamic urls

config.hosts << /[a-z0-9]+.c9users.io/

Also for ngrok user, just replace above c9users by ngrok

Source: https://github.com/MikeRogers0/puma-ngrok-tunnel