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

Gemfile

@@ -38,6 +38,7 @@ gem 'net-ldap'
 
 # Utilities
 gem "rqrcode", "~> 2.0"
+gem 'rails-settings-cached', '~> 2.8.3'
 
 # HTTP requests
 gem 'faraday'

Gemfile.lock

@@ -206,6 +206,9 @@ GEM
       nokogiri (>= 1.6)
     rails-html-sanitizer (1.4.3)
       loofah (~> 2.3)
+    rails-settings-cached (2.8.3)
+      activerecord (>= 5.0.0)
+      railties (>= 5.0.0)
     railties (7.0.4)
       actionpack (= 7.0.4)
       activesupport (= 7.0.4)
@@ -327,6 +330,7 @@ DEPENDENCIES
   pg (~> 1.2.3)
   puma (~> 4.1)
   rails (~> 7.0.2)
+  rails-settings-cached (~> 2.8.3)
   rqrcode (~> 2.0)
   rspec-rails
   sidekiq (< 7)

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 %>

db/migrate/20230217084310_create_settings.rb

@@ -0,0 +1,15 @@
+class CreateSettings < ActiveRecord::Migration[7.0]
+  def self.up
+    create_table :settings do |t|
+      t.string  :var,        null: false
+      t.text    :value,      null: true
+      t.timestamps
+    end
+
+    add_index :settings, %i(var), unique: true
+  end
+
+  def self.down
+    drop_table :settings
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.0].define(version: 2023_01_11_113139) do
+ActiveRecord::Schema[7.0].define(version: 2023_02_17_084310) do
   create_table "donations", force: :cascade do |t|
     t.integer "user_id"
     t.integer "amount_sats"
@@ -34,6 +34,14 @@ ActiveRecord::Schema[7.0].define(version: 2023_01_11_113139) do
     t.index ["user_id"], name: "index_invitations_on_user_id"
   end
 
+  create_table "settings", force: :cascade do |t|
+    t.string "var", null: false
+    t.text "value"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["var"], name: "index_settings_on_var", unique: true
+  end
+
   create_table "users", force: :cascade do |t|
     t.string "cn"
     t.string "ou"