session,model,railscast

http://railscasts.com/episodes/119-session-based-model

<br /># models/user_session.rb<br />class UserSession<br /> def initialize(session)<br /> @session = session<br /> @session[:comment_ids] ||= []<br /> end<br /> <br /> def add_comment(comment)<br /> @session[:comment_ids] << comment.id<br /> end<br /> <br /> def can_edit_comment?(comment)<br /> @session[:comment_ids].include?(comment.id) && comment.created_at > 15.minutes.ago<br /> end<br />end<br /><br /># controllers/application.rb<br />def user_session<br /> @user_session ||= UserSession.new(session)<br />end<br />helper_method :user_session<br /><br /># comments_controller.rb<br />before_filter :authorize, :only => [:edit, :update]<br /><br />def create<br /> @comment = Comment.new(params[:comment])<br /> if @comment.save<br /> user_session.add_comment(@comment)<br /> flash[:notice] = "Successfully created comment."<br /> redirect_to article_url(@comment.article_id)<br /> else<br /> render :action => 'new'<br /> end<br />end<br /><br />private<br /><br />def authorize<br /> unless user_session.can_edit_comment? Comment.find(params[:id])<br /> flash[:error] = "You are no longer able to edit this comment."<br /> redirect_to root_url<br /> end<br />end<br />
<br /><% if user_session.can_edit_comment? comment %><br /> <p><%= link_to "Edit", edit_comment_path(comment) %></p><br /><% end %><br />