Send auth_token for authentication to ActionCable

Question

module ApplicationCable
  class Connection < ActionCable::Connection::Base
    identified_by :current_user

    def connect
      #puts params[:auth_token]
      self         


        

Answer 1

I was asked about it recently and want to share the solution that I currently use in production systems.

class MyChannel < ApplicationCable::Channel
  attr_accessor :current_user

  def subscribed
    authenticate_user!
  end

  private

  # this works, because it is actually sends via the ws(s) and not via the url <3
  def authenticate_user!
    @current_user ||= JWTHelper.new.decode_user params[:token]

    reject unless @current_user
  end
end

Then re-use warden strategies to work with that JWT (and let it handle all possible edge cases and pitfalls).

class JWTHelper
  def decode_user(token)
    Warden::JWTAuth::UserDecoder.new.call token, :user, nil if token
  rescue JWT::DecodeError
    nil
  end

  def encode_user(user)
    Warden::JWTAuth::UserEncoder.new.call(user, :user, nil).first
  end
end

Though I didn't use ActionCable for the frontend it should roughly work like this:

this.cable.subscriptions.create({
  channel: "MyChannel",
  token: "YOUR TOKEN HERE",
}, //...