Make admin settings more efficient and safer.

app/controllers/admin_controller.rb

@@ -3,10 +3,8 @@ class AdminController < ApplicationController
   end
 
   def update
-    if !params[:settings].nil?
+    if params[:settings].is_a? Hash
       params[:settings].each do |key, value|
-        ## assert in list of valid settings...
-        ## only if changed (i.e. not equal to get)
         AdminSetting.set(key, value)
       end
     end

app/models/admin_setting.rb

@@ -1,12 +1,21 @@
 class AdminSetting < ActiveRecord::Base
 
+  def self.add(key, value)
+    self.create(key: key, value: value)
+  end
+
   def self.get(key)
-    Rails.cache.fetch("admin_setting/#{key}") do
-      self.find_by(key: key).value
-    end
+    existing = Rails.cache.read("admin_setting/#{key}")
+    return existing unless existing.nil?
+    setting = self.find_by(key: key)
+    return nil if setting.nil?
+    Rails.cache.write("admin_setting/#{key}", setting.value)
+    setting.value
   end
 
   def self.set(key, value)
+    existing = self.get(key)
+    return if existing.nil? || existing == value
     self.find_by(key: key).update(value: value)
     Rails.cache.write("admin_setting/#{key}", value)
   end

db/seeds.rb

@@ -6,7 +6,7 @@
 #   cities = City.create([{ name: 'Chicago' }, { name: 'Copenhagen' }])
 #   Mayor.create(name: 'Emanuel', city: cities.first)
 
-AdminSetting.create(key: 'site_name',   value: 'Your Corporation Site')
-AdminSetting.create(key: 'corporation', value: 'Your Corporation')
-AdminSetting.create(key: 'description', value: 'Your corporation\'s description goes here!')
-AdminSetting.create(key: 'copyright',   value: 'Your Corporation/Your Name')
+AdminSetting.add('site_name',   'Your Corporation Site')
+AdminSetting.add('corporation', 'Your Corporation')
+AdminSetting.add('description', 'Your corporation\'s description goes here!')
+AdminSetting.add('copyright',   'Your Corporation/Your Name')