interactor-demo

create_project.rb

class CreateProject
  include Interactor

  def call
    context.project = context.controller.current_user.projects.build(context.project_params)

    if context.project.save
      context.notice = 'Your project was created successfully.'
      send_emails_for(context.project)
    else
      context.fail!(notice: context.project.errors.full_messages)
    end
  end
  
  private
  
  def send_emails_for(project)
    AdminNotifier.project_created(project: @project).deliver
    UserNotifier.project_created(project: @project).deliver
    DesignerNotifier.project_created(project: @project).deliver
  end
end

create_project_spec.rb

require 'spec_helper'

describe CreateProject do
  describe '#call' do
    let(:user) { double(:user) }
    let(:interactor) do
      CreateProject.new(
        controller: double(:controller, current_user: user), 
        project_params: attributes_for(:project)
      )
    end
    let(:context) { interactor.context }
    
    context 'when given valid attributes' do
      let(:project) { create(:project) }
      
      before do
        allow(Project).to recieve(:save)
      end
    end
    
    context 'when given invalid attributes' do
    end
  end
end

projects_controller_after.rb

class ProjectsController < ApplicationController
  before_filter :require_login
  
  def create
    result = CreateProject.call(controller: self, project_params: project_params)

    if result.success?
      redirect_to project_path(result.project), notice: result.notice
    else
      render :new, notice: result.notice
    end
  end
end

projects_controller_before.rb

class ProjectsController < ApplicationController
  before_filter :require_login
  
  def create
    @project = current_user.projects.build(project_params)

    if @project.save
      AdminNotifier.project_created(project: @project).deliver
      UserNotifier.project_created(project: @project).deliver
      DesignerNotifier.project_created(project: @project).deliver
      
      redirect_to project_path(@project), notice: 'Your project was created successfully.'
    else
      render :new, notice: @project.errors.full_messages.join(', ')
    end
  end
end

projects_controller_spec_after.rb

require 'spec_helper'

describe ProjectsController do
  describe '#create' do
    before do
      sign_in_as(user)
      
      expect(CreateProject).to receive(:call).once.with(
        controller: controller,
        project_params: project_params
      ).and_return(context)
    end
    
    context 'when successful' do
      let(:user)           { double(:user) }
      let(:project)        { double(:project) }
      let(:context)        { double(:context, success?: true, notice: 'Your project was created successfully.', project: project) }
      let(:project_params) { attributes_for(:project) }
      
      it 'redirects to the project page' do
        expect do
          post :create, project_params
        end.to redirect_to(project_path(project))
      end
    end
    
    context 'when unsuccessful' do
      it 'renders the new project page' do
        let(:context) { double(:context, success?: false, notice: 'notice') }
          
        expect do
          post :create, attributes_for(project, :invalid)
        end.to render_template(:new)
      end
      
      it 'sets a flash notice' do
        expect do
          post :create, attributes_for(project, :invalid)
        end.to change do
          flash[:notice]
        end.from(nil).to('notice')
      end
    end
  end
end

projects_controller_spec_before.rb

require 'spec_helper'

describe ProjectsController do
  let(:user) { create(:user) }
  
  describe '#create' do
    before { sign_in_as(user) }
    
    context 'with valid project_params' do
      it 'should create a Project' do
        expect do
          post :create, attributes_for(project)
        end.to change do
          Project.count
        end.by(1)
      end
      
      it 'should notify Admin, User, and Designer' do
        expect do
          post :create, attributes_for(project)
        end.to change do
          ActionMailer::Base.deliveries.count
        end.by(3)
      end
    end
    
    context 'with invalid project_params' do
      it 'should not create a Project' do
        expect do
          post :create, attributes_for(project, :invalid)
        end.to_not change do
          Project.count
        end
      end
      
      it 'should not notify Admin, User, and Designer' do
        expect do
          post :create, attributes_for(project, :invalid)
        end.to_not change do
          ActionMailer::Base.deliveries.count
        end
      end
    end
  end
end