class Person < ActiveRecord::Base
  validates :terms_of_service, acceptance: { accept: 'yes' }
end

class UsersController < ApplicationController
  before_filter :authenticate_user!
  before_filter :admin_only, :except => :show

  def index
    @users = User.all
  end

  def show
    @user = User.find(params[:id])
    unless current_user.admin?
      unless @user == current_user
        redirect_to :back, :alert => "Access denied."
      end
    end
  end

  def update
    @user = User.find(params[:id])
    if @user.update_attributes(secure_params)
      redirect_to users_path, :notice => "User updated."
    else
      redirect_to users_path, :alert => "Unable to update user."
    end
  end

  def destroy
    user = User.find(params[:id])
    user.destroy
    redirect_to users_path, :notice => "User deleted."
  end

  private

  def user_params
    params.require(:user).permit(:name, :email, :terms_accepted)
  end

  def admin_only
    unless current_user.admin?
      redirect_to :back, :alert => "Access denied."
    end
  end

  def secure_params
    params.require(:user).permit(:role)
  end
end

---
class User < ActiveRecord::Base
  validates :terms_accepted, acceptance: { accept: 'yes' }

  enum role: [:user, :vip, :admin]
  after_initialize :set_default_role, :if => :new_record?


  def set_default_role
    self.role ||= :user
  end

  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable and :omniauthable
  devise :invitable, :database_authenticatable, :registerable, :confirmable,
         :recoverable, :rememberable, :trackable, :validatable
  end
---

<div class="row">
  <div class="col-md-6">
    <%= form_for(resource, :as => resource_name, :url =>     registration_path(resource_name), :html => { :role => 'form'}) do |f| %>
        <h2 class="form-signin-heading">Sign Up</h2>
        <%= devise_error_messages! %>
        <div class="form-group">
          <%= f.label :name %>
          <%= f.text_field :name, :autofocus => true, class: 'form-control' %>
        </div>
        <div class="form-group">
          <%= f.label :email %>
          <%= f.email_field :email, class: 'form-control' %>
        </div>
        <div class="form-group">
          <%= f.label :password %>
          <%= f.password_field :password, class: 'form-control' %>
        </div>
            <div class="form-group">
          <%= f.label :confirm_password %>
          <%= f.password_field :password_confirmation, class: 'form-control' %>
        </div>
        <div class="form-group">
          <%= f.check_box :terms_accepted%>
          <%= f.label :accept_terms %>
          <%= link_to 'Terms Of Use', '/TermsOfUse.html', :target => "_blank" %>
        </div>
        <div class="form-group">
          <%= f.submit 'Sign Up', :class => 'btn btn-lg btn-login' %>
        </div>
        <div class="form-group">
          <%= render "devise/shared/links" %>
        </div>
    <% end %>
 </div>

Started GET "/" for ::1 at 2015-06-29 13:55:55 -0700
Processing by VisitorsController#index as HTML
   (0.5ms)  SELECT COUNT(*) FROM "users"
  Rendered visitors/index.html.erb within layouts/application (1.6ms)
  Rendered layouts/_flatlabnavbartop.html.haml (16.2ms)
Completed 200 OK in 347ms (Views: 345.7ms | ActiveRecord: 0.5ms)

Started GET "/users/sign_up" for ::1 at 2015-06-29 13:56:00 -0700
Processing by DeviseInvitable::RegistrationsController#new as HTML
  Rendered /usr/local/rvm/gems/ruby-2.2.1@suits6/gems/devise-3.4.1/app/views/devise/shared/_links.html.erb (1.4ms)
  Rendered devise/registrations/new.html.erb within layouts/application (51.9ms)
  Rendered layouts/_flatlabnavbartop.html.haml (1.9ms)
Completed 200 OK in 279ms (Views: 277.9ms | ActiveRecord: 0.0ms)


Started POST "/users" for ::1 at 2015-06-29 13:56:29 -0700
Processing by DeviseInvitable::RegistrationsController#create as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"4t0UPaQhI/0HcsqC3RkBrcWQWjhWzKojZLvrMloObPSAiapVc46bvxT5TGePh4v2IUCi8QbdVuMWuQsyzyFmdg==", "user"=>{"name"=>"Maude Username", "email"=>"maude@gmail.com", "password"=>"[FILTERED]", "password_confirmation"=>"[FILTERED]", "terms_accepted"=>"1"}, "commit"=>"Sign Up"}

Unpermitted parameter: terms_accepted

  User Load (119.8ms)  SELECT  "users".* FROM "users" WHERE "users"."email" = $1 AND "users"."encrypted_password" = $2  ORDER BY "users"."id" ASC LIMIT 1  [["email", "maude@gmail.com"], ["encrypted_password", ""]]

   (0.2ms)  BEGIN
  User Exists (16.6ms)  SELECT  1 AS one FROM "users" WHERE "users"."email" = 'maude@gmail.com' LIMIT 1

   (8.3ms)  ROLLBACK
  Rendered /usr/local/rvm/gems/ruby-2.2.1@suits6/gems/devise-3.4.1/app/views/devise/shared/_links.html.erb (0.7ms)

  Rendered devise/registrations/new.html.erb within layouts/application (18.5ms)

  Rendered layouts/_flatlabnavbartop.html.haml (2.9ms)

Completed 200 OK in 733ms (Views: 383.5ms | ActiveRecord: 144.9ms)