TypeError in SessionsController#create when trying to sign in user from Twitter API using omniauth

Question

I am trying to allow users to sign in through Twitter but I am getting the error: Type error in SessionsController. I get this error whenever I am redirected to: https://api.twitter.com/oauth/authenticate so the user can be authenticated. I should be redirected to the Twitter "Authorize App" page after being authenticated, but I am receiving the full error: "TypeError in SessionsController#create: exception class/object expected". I am using the omniauth_twitter and devise gems for this functionality. Am I missing something that I need to do for devise in the routes.rb file possibly?

Also it makes it through the create method(in the SessionController) as it does end up redirecting to the root page, but I don't see the user created in the database.

Session Controller

 class SessionsController < ApplicationController

 def create
  @user = User.find_or_create_from_auth_hash(auth_hash)
  session[:user_id] = @user.id
  redirect_to root_path
 end

 protected

 def auth_hash
  request.env['omniauth.auth']
 end
end

User Model

class User < ActiveRecord::Base
 devise :database_authenticatable, :registerable,
     :recoverable, :rememberable, :trackable, :validatable

 before_create :generate_auth_token

def self.find_or_create_from_auth_hash(auth_hash)
user = where(provider: auth_hash.provider, uid:   auth_hash.uid).first_or_create
user.update(
  name: auth_hash.info.name,
  avatar: auth_hash.info.image,
  token: auth_hash.credentials.token,
  secret: auth_hash.credentials.secret)
user
end

 def generate_auth_token
 loop do 
  self.auth_token = SecureRandom.base64(64)
  break unless User.find_by(auth_token)
 end   
end
end

Routes.rb

Rails.application.routes.draw do
   get 'auth/:provider/callback', to: 'sessions#create'

   resources :tweets

   get 'signup/new'

   get 'signup/create'


   devise_for :users


   resources :contacts
  end

Also the User is not showing in the database it should be saved down

Loading production environment (Rails 4.2.1)
[1] pry(main)> User.all
User Load (3.2ms)  SELECT "users".* FROM "users"
=> []

Answer 1

You're seeing this error because 1) you're raising an exception in SessionsController#create (raise :test) and 2) raise is not expecting a symbol, which is why you're seeing that cryptic error message.

λ irb
2.3.1 :001 > raise :test
TypeError: exception class/object expected
        from (irb):1:in `raise'
        from (irb):1
        from /home/peter/.rvm/rubies/ruby-2.3.1/bin/irb:11:in `<main>'

You should remove the call to raise if it's not actually supposed to be there or, if it is, call raise with a legitimate argument (string, exception instance, etc.) and rescue accordingly.