The document summarizes some ways to avoid duplicate code in Ruby on Rails applications, including using scopes and modules in models, adding before_actions and private methods in controllers, and utilizing partials and nested layouts in views. Presenter Bui Trung Kien from Framgia Inc discusses techniques for DRYing up model, controller, and view code.

1. Seminar
Some ways to DRY in Rails
Presenter: Bui Trung Kien – Framgia Inc

2. Content
●
Model
●
Controller
●
Views

3. Model
●
Use 'scope'
scope :admin, ->{where(admin: true)}
●
Use 'module'
app/model/concern/set_user.rb
module SetUser
//code goes here
end
app/model/user.rb
class Admin < ActiveRecord::Base
include SetUser

4. Controller
●
Use 'before_action'
app/controllers/users_controller.rb
class UsersController < ApplicationController
before_action :set_user,
only: [:show, :edit, :update, :destroy]
.
.
.
private
def set_user
@user = User.find params[:id]
end

5. Controller
Use respond_with and respond_to
class UsersController <
ApplicationController
respond_to :html, :json, :xml
def index
@users = User.all
respond_with @users
end

6. Controller
●
Move business code logic into model methods.
●
Move view logic code into helper methods.
And then try to DRY it up.

7. View
●
Use 'partial'.
●
Use nested layout.

8. THANKS FOR WATCHING