Devise ERROR: Auth token has already been taken - ruby-on-rails

Question

Trying to signup in my RoR webapp give me the Devise Message "Auth token has already been taken"
Also, the webapp have an API and works fine, doesn't give any message, this only happen when I'm trying to use the HTML view.
user_controller.rb
before_action :set_user, only: [:show, :edit, :update, :destroy]
# DELETE /users/:id.:format
def destroy
# authorize! :delete, #user
#user.destroy
respond_to do |format|
format.html { redirect_to root_url }
end
end
private
def set_user
#user = User.find(params[:id])
end
def user_params
accessible = [ :name, :email ]
accessible << [ :password, :password_confirmation ] unless params[:user][:password].blank?
params.require(:user).permit(accessible)
end
User.rb
validates :auth_token, uniqueness: true
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
before_create :generate_authentication_token!
def generate_authentication_token!
begin
self.auth_token = Devise.friendly_token
end while self.class.exists?(auth_token: auth_token)
end
logs
Started GET "/users/sign_up" for 127.0.0.1 at 2015-06-30 09:31:46 -0500
Processing by Devise::RegistrationsController#new as HTML
Rendered devise/registrations/new.html.haml within layouts/application (12.9ms)
User Load (0.3ms) SELECT "users".* FROM "users" WHERE "users"."deleted_at" IS NULL AND "users"."auth_token" IS NULL LIMIT 1
Rendered layouts/_navigation_links.html.haml (2.1ms)
Rendered layouts/_navigation.html.haml (3.4ms)
Rendered layouts/_messages.html.haml (0.2ms)
Completed 200 OK in 132ms (Views: 117.0ms | ActiveRecord: 1.5ms)
Started POST "/users" for 127.0.0.1 at 2015-06-30 09:32:00 -0500
Processing by Devise::RegistrationsController#create as HTML
Parameters: {"utf8"=>"✓", "authenticity_token"=>"20w9AXmACwggvPocKfLBdrxQRasT5OiaC7niuzooBBm3BAp8xkN6VLWyxZLRoLIpFPEIIdkxZRd9CCwsJxkeUA==", "user"=>{"email"=>"hola#x.com", "password"=>"[FILTERED]", "password_confirmation"=>"[FILTERED]"}, "commit"=>"Sign up"}
(0.1ms) BEGIN
User Exists (0.4ms) SELECT 1 AS one FROM "users" WHERE "users"."auth_token" = '' LIMIT 1
User Exists (0.3ms) SELECT 1 AS one FROM "users" WHERE "users"."email" = 'hola#x.com' LIMIT 1
(0.1ms) ROLLBACK
Rendered devise/registrations/new.html.haml within layouts/application (3.2ms)
User Load (0.3ms) SELECT "users".* FROM "users" WHERE "users"."deleted_at" IS NULL AND "users"."auth_token" IS NULL LIMIT 1
Rendered layouts/_navigation_links.html.haml (1.5ms)
Rendered layouts/_navigation.html.haml (2.1ms)
Rendered layouts/_messages.html.haml (0.2ms)
Completed 200 OK in 232ms (Views: 134.4ms | ActiveRecord: 1.2ms)
Started GET "/assets/jquery/jquery-bb5529929fa5581a780a38ecb7470f2c.js?body=1" for 127.0.0.1 at 2015-06-30 09:32:00 -0500

Answer 1

Follow the following
1) Open Rails console
rails console
2) Get the total count of users
user = User.all
user.count
this should be 1
3) Get the user and check the auth token
user = User.last
user.auth_token
auth token would be an empty string which is the reason your command is failing as the user doesn't have valid auth token
4) Create a valid auth token for the user
user.auth_token = Devise.friendly_token
user.save
It would create a valid auth token for the user and save it
5) Now you can run your commands and it would work perfectly
Cheers! :)

Answer 2

It's probably because you already have users in your db without auth_token,
use Devise.friendly_token to update those users with a token