GraphQL resolver example with tests

resolver.rb

module Resolvers
  class CreateEvent
    include Pundit

    def self.call(*args)
      new(*args).resolve
    end

    attr_reader :current_user

    def initialize(_obj, args, ctx)
      @organization_id = args[:organizationId]
      @current_user = ctx[:current_user]
      @params = args[:input].to_h.with_indifferent_access
      @questions = @params.delete(:questions) || []
    end

    def resolve
      raise Pundit::NotAuthorizedError if current_user.blank? || !authorized?
      build_questions
      if event.save
        event
      else
        GraphQL::ExecutionError.new(@event.errors.details.to_json)
      end
    end

    private

    def authorized?
      authorize event, :create?
    end

    def organization
      ::Organization.find(@organization_id)
    end

    def build_questions
      @questions.each do |question|
        event.questions.build(question)
      end
    end

    def event
      @event ||= organization.events.build(@params)
    end
  end
end

resolver_spec.rb

require 'rails_helper'

RSpec.describe Resolvers::CreateEvent do
  describe 'resolve create event mutation' do
    let!(:organization) { create(:organization) }
    let!(:args) do
      {
        organizationId: organization.id,
        input: attributes_for(:event)
      }
    end
    let(:user) { create(:user) }

    let(:context) { { current_user: user } }

    context 'when an user has access to the organization' do
      before { organization.users << user }

      context 'with questions' do
        let!(:args) do
          {
            organizationId: organization.id,
            input: attributes_for(:event).merge(
              questions: [
                { title: 'How well were you treated?', question_type: :rating }
              ]
            )
          }
        end
        it 'creates a new event' do
          described_class.call(nil, args, context)
          expect(organization.events.count).to eq 1
          event = organization.events.first
          expect(event.questions.count).to eq 1
        end
      end
    end
  end
end