title: undefined method `session_path'
body: <p>I am using Rails + Devise + OmniAuth + Google OAuth2.</p>
  
  <p>My user model (user.rb) contains:</p>
  
  <pre><code>devise :registerable, :omniauthable, :omniauth_providers =&gt; [:google_oauth2]
  </code></pre>
  
  <p>My routes.rb look like:</p>
  
  <pre><code>Rails.application.routes.draw do
    devise_for :users, controllers: { omniauth_callbacks: 'omniauth_callbacks' }
    devise_scope :user do
        get 'sign_in', :to =&gt; 'devise/sessions#new', :as =&gt; :new_user_session
        post 'sign_in', :to =&gt; 'devise/session#create', :as =&gt; :user_session
        get 'sign_out', :to =&gt; 'devise/sessions#destroy', :as =&gt; :destroy_user_session
    end
  
    get 'services', to: 'static_pages#services'
    get 'my_account', to: 'my_account#index'
    get 'invite', to: 'invite#show'
    get 'invite/:id', to: 'invite#show'
  
    root 'static_pages#home'
  end
  </code></pre>
  
  <p>When I go to /sign_in, I get an exception like:</p>
  
  <pre><code>undefined method `session_path' for #&lt;#&lt;Class:0x007f9b7173af28&gt;:0x007f9b713d8da8&gt;
  </code></pre>
  
  <p>in:</p>
  
  <pre><code>~/.rvm/gems/ruby-2.1.1/gems/devise-3.2.4/app/views/devise/sessions/new.html.erb
  </code></pre>
  
  <p>in line:</p>
  
  <pre><code>&lt;%= form_for(resource, as: resource_name, url: session_path(resource_name)) do |f| %&gt;
  </code></pre>
  
  <p>If I add :database_authenticatable to user.rb it all starts working, but I want my users to be able to sign-in through Google OAuth2 only, so I don't want :database_authenticable. It looks like session_path is not available for some reason, but I am not sure why and how to make it available.</p>
  
  <p>Thanks,
  Jen</p>