Delegate Pattern With Rails

commands.bash

rails generate model User first_name:string last_name:string email:string

rails generate Profile tagline user:references
rails db:migrate

User.create({name: 'Danilo Velozo', email: 'velozo.dan@gmail.com', password: '12345', password_confirmation: '12345'})

Profile.create(tagline: 'My Awesome Profile', user_id: User.first.id)

# Or

Profile.create(tagline: 'My Awesome Profile', user: User.first)

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# The delegate method allows you to optionally pass allow_nil and a prefix as well.

rails c
profile = Profile.first
profile.email #= "velozo.dan@gmail.com"
profile.username #= "Danilo Velozo"

profile.rb

# app/models/profile.rb

class Profile < ApplicationRecord
  belongs_to :user

  delegate :username, :email, to: :user, allow_nil: true, prefix: :user
end

user.rb

# app/models/user.rb

class User < ApplicationRecord
  has_person_name
  has_one :profile

  delegate :username, to: :profile

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

  def username
    "#{first_name}_#{last_name}"
  end
end