Add rails-settings-cached, use for initial feature flags

app/controllers/admin/lightning_controller.rb

@@ -13,7 +13,7 @@ class Admin::LightningController < Admin::BaseController
   end
 
   def check_feature_enabled
-    if ENV["LNDHUB_ADMIN_UI"].empty?
+    if !Setting.lndhub_admin_enabled?
       flash[:alert] = "Lightning Admin UI not enabled"
       redirect_to admin_root_path and return
     end

app/models/setting.rb

@@ -0,0 +1,7 @@
+# RailsSettings Model
+class Setting < RailsSettings::Base
+  cache_prefix { "v1" }
+
+  field :lndhub_enabled, default: (ENV["LNDHUB_API_URL"].present?.to_s || "false"), type: :boolean
+  field :lndhub_admin_enabled, default: (ENV["LNDHUB_ADMIN_UI"] || "false"), type: :boolean
+end

app/views/shared/_admin_nav.html.erb

@@ -6,7 +6,7 @@
       class: main_nav_class(@current_section, :invitations) %>
 <%= link_to "Donations", admin_donations_path,
       class: main_nav_class(@current_section, :donations) %>
-<% if ENV["LNDHUB_ADMIN_UI"] %>
+<% if Setting.lndhub_admin_enabled? %>
   <%= link_to "Lightning", admin_lightning_path,
         class: main_nav_class(@current_section, :lightning) %>
 <% end %>