Build modern Rails applications with MVC architecture, Active Record, Hotwire, and production-ready patterns.
Core Patterns
Controller
class UsersController < ApplicationController
before_action :set_user, only: [:show, :edit, :update, :destroy]
def index
@users = User.all
end
def create
@user = User.new(user_params)
if @user.save
redirect_to @user, notice: 'User created successfully'
else
render :new, status: :unprocessable_entity
end
end
private
def set_user @user = User.find(params[:id]) end
def user_params params.require(:user).permit(:name, :email) end end
### Model
```ruby
class User < ApplicationRecord
has_many :posts, dependent: :destroy
validates :email, presence: true, uniqueness: true
validates :name, presence: true, length: { minimum: 2 }
scope :active, -> { where(active: true) }
def full_name
"#{first_name} #{last_name}"
end
end
Service Object
class UserRegistrationService
def initialize(user_params)
@user_params = user_params
end
def call
User.transaction do
user = User.create!(@user_params)
send_welcome_email(user)
user
end
rescue ActiveRecord::RecordInvalid => e
OpenStruct.new(success?: false, error: e.message)
end
private
def send_welcome_email(user)
UserMailer.welcome(user).deliver_later
end
end
Best Practices
- Follow Rails conventions
- Use service objects for complex logic
- Implement proper validations
- Use concerns for shared behavior
- Write comprehensive tests
- Use background jobs
- Implement caching
- Follow RESTful routing