The Guest User

What is a Guest User?

By convention, a Guest User is a User Entity with whatever attributes your UserRepository says a Guest User has. This will often be mirrored in your User Entity class itself, so that code can ask a User Entity if it's a Guest User without having to know what defines it as such.

For example:

In lib/your_stuff/entities/user.rb

# frozen_string_literal: true

class User < Hanami::Entity
  GUEST_EMAIL = '[email protected]'
  GUEST_NAME = 'Guest User'
  GUEST_PROFILE = 'This is the Guest User. It can do nothing.'

  def guest?
    name == GUEST_NAME && email == GUEST_EMAIL && profile == GUEST_PROFILE
  end
end

and in lib/your_stuff/repositories/user_repository.rb

# frozen_string_literal: true

require 'securerandom'

class UserRepository < Hanami::Repository
  # ... associations, finders, etc ...

  def self.guest_user
    @guest_user ||= entity.new name: User::GUEST_NAME, email: User::GUEST_EMAIL,
                               password_hash: SecureRandom.alphanumeric(48),
                               profile: User::GUEST_PROFILE, id: -1
  end

  def guest_user
    self.class.guest_user
  end
end

Note that the Entity's #guest? method doesn't simply compare against the Repository's .guest_user returned Entity, as the latter has an unmatchable password_hash attribute. ("But doesn't this violate SRP", I hear you asking back there? No, because there is still a single source of truth for "what makes a Guest a Guest": the constant definitions on the User class that are used by the UserRepository.

Got a better idea? Open an issue or, better yet, a PR and let's talk about it!