You might get this error if you’re using Rails Edge: config.breakpoint_server has been deprecated and has no effect:

To fix the error we need to remove the following from config/environments/development.rb:

   1  config.breakpoint_server = true

Next install ruby-debug:

   1  gem install ruby-debug

Then add this to the end of config/environments/development.rb:

   1  require 'ruby-debug'

Next, start your server, and the error should be gone…

To debug your code just add a call to debugger:

   1  class MySillySpace ...
   2    def create
   3      debugger # add this line
   4    end

Now when you access the URL with your browser you’ll have access to the debugger from the console window.

To learn how to use ruby-debug, read this tutorial written by the ruby-debug author.