devise's sign_in_and_redirect method logged me in but spree does not recognize it

[shivabhusal]

Problem

I am developing a store as a separate app to be integrated with my another app via APIs. I have used doorkeeper as OAuth2 provider. The code below is from the Oauth callback which is called when user is successfully validated by OAuth2 provider base-app.

in line sign_in_and_redirect @user, :event => :authentication I intend to signin with the validated user and redirect. The Login button in home page was still visible.

While moving to the code base I found that it checks if spree_current_user is present or not.

<% if spree_current_user %>
  <li><%= link_to Spree.t(:my_account), spree.account_path %></li>
  <li><%= link_to Spree.t(:logout), spree.logout_path %></li>
<% else %>
  <li id="link-to-login"><%= link_to Spree.t(:login), spree.login_path %></li>
<% end %>

But the sign_in_and_redirect is supposed to set the spree_current_user but it was not.

After prying I found

pry(#<Users::OmniauthCallbacksController>)> current_user
=> #<Spree::User:0x007f1efc2b3208
 id: 4,
 encrypted_password: nil,
 password_salt: nil,


pry(#<Users::OmniauthCallbacksController>)> spree_current_user
=> nil

Question:

How can I let users signin and also set spree_current_user so that my users signed in via SSO no more see the Login button even after logged in.
Thanks :)

Code sample

class Users::OmniauthCallbacksController < Devise::OmniauthCallbacksController
  def the_pact
    # You need to implement the method below in your model (e.g. app/models/user.rb)
    @user = Spree::User.from_omniauth(request.env["omniauth.auth"])

    if @user.persisted?
      sign_in_and_redirect @user, :event => :authentication #this will throw if @user is not activated
      set_flash_message(:notice, :success, :kind => "ThePact") if is_navigational_format?
    else
      session["devise.the_pact_data"] = request.env["omniauth.auth"]
      redirect_to new_user_registration_url
    end
  end

  def failure
    redirect_to root_path
  end
end

Libraries used:

Rails: **4.2.5.1**
Spree: 3.0.5
spree_auth_devise: 3.0.0
devise (~> 3.4.1)

[shivabhusal]

BTW

I did this

class ApplicationController < ActionController::Base
  # Prevent CSRF attacks by raising an exception.
  # For APIs, you may want to use :null_session instead.
  protect_from_forgery with: :exception

  def spree_current_user
    current_user
  end

end

Is there any better way to do this?