Module: ModelPresenter::HasMany

Defined in:
lib/model_presenter/has_many.rb

Instance Method Summary collapse

Instance Method Details

#has_many(relation, options) ⇒ Object

The DSL adds an instance method relation to represnet a has_many relationship

class User
  include ModelPresenter::Base
  has_many :groups, presenter_class: Presenters::Group
end

The macro will generates a groups methods, which will return an array. Each element of the array is an instance of Presenters::Group whose model is one of the group models that the user has.

Parameters:

  • relation (Symbol, #read) —

    the name of the relationship

  • options (Hash, #read) —

    Currently it accepts one key presenter_class is a class. The class is supposed to be a presenter class. The relation method will return an array of elements that are instances of the class

Returns:

  • none



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# File 'lib/model_presenter/has_many.rb', line 17

def has_many(relation, options)
  self.send :define_method, relation do
    instance_variable_name = "@#{relation}"
    instance_variable = instance_variable_get("@#{relation}")
    return instance_variable if instance_variable
    instance_variable_set(
      instance_variable_name,
      model.send(relation).map do |relation_model|
        options[:presenter_class].new relation_model
      end
    )
  end
end