kermit-klein

class Validator {
  static REQUIRED = "REQUIRED";
  static MIN_LENGTH = "MIN_LENGTH";
  static validate(value, flag, validatorValue) {
    if (flag === this.REQUIRED) {
      return value.trim().length > 0;
    }
    if (flag === this.MIN_LENGTH) {
      return value.trim().length > validatorValue;
    }

kermit-klein

const REQUIRED = "REQUIRED";
const MIN_LENGTH = "MIN_LENGTH";

const validate = (value, flag, validatorValue) => {
  if (flag === REQUIRED) {
    return value.trim().length > 0;
  }
  if (flag === MIN_LENGTH) {
    return value.trim().length > validatorValue;
  }

kermit-klein

class Manifest < ActiveRecord::Base
  validates :name, presence: true
  validates :description, presence: true
  
  def outdate
    self.status = :outdated
  end
  
  def active?
    self.status != :outdated

kermit-klein

class Manifest < ActiveRecord::Base
  validates :name, presence: true
  validates :description, presence: true
end

kermit-klein

class Assembly < ApplicationRecord
  has_many :manifests
  has_many :parts, through: :manifests
end
 
class Manifest < ApplicationRecord
  belongs_to :assembly
  belongs_to :part
end

kermit-klein

class Assembly < ApplicationRecord
  has_and_belongs_to_many :parts
end
 
class Part < ApplicationRecord
  has_and_belongs_to_many :assemblies
end

kermit-klein

class CreateReviews < ActiveRecord::Migration[6.0]
  def change
    create_table :reviews do |t|
      t.references :reviewable, polymorphic: true, index: true
      t.string :body
      t.timestamps
    end
  end
end

kermit-klein

class Review < ApplicationRecord
# name the interface to the Review model reviewable
# establish that it is polymorphic
belongs_to :reviewable, polymorphic: true
end

class Restaurant < ApplicationRecord
# establish a relationship to the Review model 
# via the reviewable interface
has_many :reviews, as: :reviewable

kermit-klein

class User
  has_and_belongs_to_many :groups
end

class Group
  has_and_belongs_to_many :users
end

kermit-klein

class User
  has_one :profile
  has_one :avatar, through: :profile
end

class Profile
  belongs_to :user
  has_one :avatar
end