module ApplicationCable
class Connection < ActionCable::Connection::Base
identified_by :current_user
def connect
#puts params[:auth_token]
self
Pierre's answer works. However, it's a good idea to be explicit about expecting these parameters in your application.
For instance, in one of your config files (e.g. application.rb, development.rb, etc...) you can do this:
config.action_cable.mount_path = '/cable/:token'
And then simply access it from your Connection class with:
request.params[:token]