Question

I am getting undefined method `[]’ for nil:NilClass

 NoMethodError in Users::OmniauthCallbacksController#facebook

  undefined method `[]' for nil:NilClass

  Rails.root: /home/krishna/picer
  Application Trace | Framework Trace | Full Trace

  app/models/user.rb:13:in `find_for_facebook_oauth'
  app/controllers/users/omniauth_callbacks_controller.rb:4:in `facebook'

This is my user.rb code

class User < ActiveRecord::Base
# Include default devise modules. Others available are:
# :token_authenticatable, :encryptable, :confirmable, :lockable, :timeoutable:omniauthable
devise :database_authenticatable, :registerable,
     :recoverable, :rememberable, :trackable, :validatable,
     :omniauthable

# Setup accessible (or protected) attributes for your model
attr_accessible :email, :password, :password_confirmation, :remember_me

def self.find_for_facebook_oauth(access_token, signed_in_resource=nil)
data = access_token['extra']['user_hash']
if user = User.find_by_email(data["email"])
  user
else # Create a user with a stub password.
  User.create(:email => data["email"], :password => Devise.friendly_token[0,20])
  end
end

 def self.new_with_session(params, session)
  super.tap do |user|
    if data = session["devise.facebook_data"] && session["devise.facebook_data"]  ["extra"]["user_hash"]
    user.email = data["email"]
   end
  end
 end
end

And omniauth callbacks controller code

 class Users::OmniauthCallbacksController < Devise::OmniauthCallbacksController
 def facebook
 # You need to implement the method below in your model
 @user = User.find_for_facebook_oauth(request.env["omniauth.auth"], current_user)

if @user.persisted?
  flash[:notice] = I18n.t "devise.omniauth_callbacks.success", :kind => "Facebook"
  sign_in_and_redirect @user, :event => :authentication
else
  session["devise.facebook_data"] = env["omniauth.auth"]
  redirect_to new_user_registration_url
 end
end

def passthru
  render :file => "#{Rails.root}/public/404.html", :status => 404, :layout => false
 end

end

I am getting error line four user.rb I used a example for this https://github.com/ryanatwork/devise-omniauth

Answer 1

You should get the user email with access_token['info']['email'] instead of access_token['extra']['user_hash']['email'].

I don’t think the data in access_token['extra'] follows a convention like the rest, so you should be extra careful and test if the property you’re trying to access exists. It’s not that important if you only have one provider, but it is if you have several of them.