Add login_options as a permitted param; add rpi_auth_signup_path

Author: patch0

README.md

@@ -96,7 +96,13 @@ link_to 'Log in', rpi_auth_login_path, method: :post
 button_to 'Log in', rpi_auth_login_path
 ```
 
-There is also a helper for the logout route:
+There is a helper for the sign-up buttons, which pushes the user through the sign-up flow.
+
+```ruby
+button_to 'Sign up', rpi_auth_signup_path
+```
+
+And there is also a helper for the logout route:
 
 ```ruby
 link_to 'Log out', rpi_auth_logout_path

config/routes.rb

@@ -1,10 +1,11 @@
 # frozen_string_literal: true
 
 Rails.application.routes.draw do
-  # Dummy route. This route is never reached in the app, as Omniauth intercepts
-  # it via Rack middleware before it reaches Rails, however adding this route
-  # allows us to use rpi_auth_login_path helpers etc.
+  # Dummy routes. These routes are never reached in the app, as Omniauth
+  # intercepts it via Rack middleware before it reaches Rails, however adding
+  # them allows us to use rpi_auth_login_path helpers etc.
   post '/auth/rpi', as: :rpi_auth_login
+  post '/auth/rpi', as: :rpi_auth_signup, params: { login_options: 'force_signup,v1_signup' }
 
   namespace 'rpi_auth' do
     get '/auth/callback', to: 'auth#callback', as: 'callback'

lib/rpi_auth/engine.rb

@@ -36,6 +36,7 @@ class Engine < ::Rails::Engine
             jwks_uri: RpiAuth.configuration.jwks_uri
           },
           extra_authorize_params: { brand: RpiAuth.configuration.brand },
+          allow_authorize_params: [ :login_options ],
           origin_param: 'returnTo'
         )
 

spec/dummy/app/views/home/show.html.erb

@@ -7,6 +7,8 @@
   <% else %>
     <%= button_to 'Log in', rpi_auth_login_path, method: :post %>
     <br />
-    <%= link_to 'Log in GET', rpi_auth_login_path %>
+    <%= link_to 'Log in GET', rpi_auth_login_path %> (should 404)
+    <br />
+    <%= button_to 'Sign up', rpi_auth_signup_path, method: :post %>
   <% end %>
 </p>