Require authentication for most endpoints (#29)

Reviewed-on: #29

app/controllers/concerns/authorizable.rb

@@ -0,0 +1,37 @@
+module Authorizable
+  extend ActiveSupport::Concern
+
+  included do
+    before_action :require_registered_user
+  end
+
+  class_methods do
+    def allow_unregistered_user(**args)
+      skip_before_action :require_registered_user, **args
+    end
+
+    def require_unregistered_user(**args)
+      skip_before_action :require_registered_user, **args
+      before_action :require_unregistered_user, **args
+    end
+  end
+
+  private
+
+  def require_registered_user
+    Current.user.registered? || redirect_to_sign_in
+  end
+
+  def require_unregistered_user
+    Current.user.unregistered? || redirect_to_dashboard
+  end
+
+  def redirect_to_sign_in
+    session[:return_url] = request.url
+    redirect_to new_session_url, alert: "You must be logged in to continue."
+  end
+
+  def redirect_to_dashboard
+    redirect_to root_url, alert: "You are already logged in."
+  end
+end