Replace method_missing per explicit delegation

To avoid as much magic as possible

Makefile

@@ -259,6 +259,8 @@ WORKING_SPECS_9 = \
 	services/geocoder/spec/hires_geocoder_factory_spec.rb \
 	services/table-geocoder/spec/geocoder_cache_spec.rb \
 	services/user-mover/spec/user_mover_spec.rb \
+	spec/presenters/base_presenter_spec.rb \
+	spec/presenters/organization_presenter_spec.rb \
 	$(NULL)
 
 # Tests using spec_helper_min instead of spec_helper

app/presenters/base_presenter.rb

@@ -2,17 +2,17 @@ class BasePresenter
 
   attr_accessor :object, :params
 
-  def initialize(object, params = {})
+  def self.object_klass
-    @object = object
+    raise 'Must be overriden in child class'
-    @params = params
   end
 
-  def method_missing(*args, &block)
+  def self.delegated_methods
-    object.send(*args, &block)
+    object_klass.columns.map(&:name).map(&:to_sym) + object_klass.instance_methods
   end
 
-  def respond_to_missing?(method_name, _include_private = false)
+  def initialize(object, params = {})
-    object.respond_to?(method_name)
+    @object = object
+    @params = params
   end
 
 end

app/presenters/organization_presenter.rb

@@ -1,5 +1,14 @@
 class OrganizationPresenter < BasePresenter
 
+  def self.object_klass
+    Carto::Organization
+  end
+
+  # rubocop:disable Style/AccessModifierDeclarations
+  protected(*delegate(*delegated_methods, to: :object))
+  # rubocop:enable Style/AccessModifierDeclarations
+  delegate(:owner, :unassigned_quota, :db_size_in_bytes, to: :object)
+
   def data
     params[:extended] ? extended_representation : default_representation
   end

spec/presenters/base_presenter_spec.rb

@@ -0,0 +1,27 @@
+require 'spec_helper'
+
+describe BasePresenter do
+  class DummyPresenter < BasePresenter
+
+    def self.object_klass
+      Carto::Organization
+    end
+
+    # rubocop:disable Style/AccessModifierDeclarations
+    private(*delegate(*delegated_methods, to: :object))
+    # rubocop:enable Style/AccessModifierDeclarations
+
+    def data
+      { id: id }
+    end
+
+  end
+
+  let(:organization) { create(:carto_organization) }
+  let(:presenter) { DummyPresenter.new(organization) }
+
+  it 'delegates basic methods to inner object while keeping them private' do
+    expect(presenter.data[:id]).to eq(organization.id)
+    expect { presenter.id }.to raise_error(NoMethodError)
+  end
+end

spec/presenters/organization_presenter_spec.rb

@@ -0,0 +1,25 @@
+require 'spec_helper'
+
+describe OrganizationPresenter do
+  let(:user) { create(:carto_user, period_end_date: Time.parse('2018-01-01')) }
+  let(:organization) { create(:carto_organization, owner: user) }
+  let(:presenter) { described_class.new(organization) }
+  let(:date_range) { { Date.new(2017, 3, 20) => 1 } }
+
+  describe '#data' do
+    before do
+      CartoDB::ServiceUsageMetrics.any_instance.stubs(:get_date_range).returns(date_range)
+    end
+
+    it 'returns the default representation' do
+      expect(presenter.data[:id]).to eq(organization.id)
+      expect(presenter.data[:owner][:username]).to eq(organization.owner.username)
+    end
+
+    it 'returns extra attributes for the extended representation' do
+      presenter = described_class.new(organization, extended: true)
+
+      expect(presenter.data[:table_count]).to eq(0)
+    end
+  end
+end