Add update on-call schedule service

ee/app/services/incident_management/oncall_schedules/update_service.rb

+# frozen_string_literal: true
+
+module IncidentManagement
+  module OncallSchedules
+    class UpdateService
+      # @param oncall_schedule [IncidentManagement::OncallSchedule]
+      # @param user [User]
+      # @param params [Hash]
+      def initialize(oncall_schedule, user, params)
+        @oncall_schedule = oncall_schedule
+        @user = user
+        @params = params
+        @project = oncall_schedule.project
+      end
+
+      def execute
+        return error_no_license unless available?
+        return error_no_permissions unless allowed?
+
+        if oncall_schedule.update(params)
+          success(oncall_schedule)
+        else
+          error(oncall_schedule.errors.full_messages.to_sentence)
+        end
+      end
+
+      private
+
+      attr_reader :oncall_schedule, :user, :params, :project
+
+      def allowed?
+        user&.can?(:admin_incident_management_oncall_schedule, project)
+      end
+
+      def available?
+        Feature.enabled?(:oncall_schedules_mvc, project) &&
+          project.feature_available?(:oncall_schedules)
+      end
+
+      def error(message)
+        ServiceResponse.error(message: message)
+      end
+
+      def success(oncall_schedule)
+        ServiceResponse.success(payload: { oncall_schedule: oncall_schedule })
+      end
+
+      def error_no_permissions
+        error(_('You have insufficient permissions to update an on-call schedule for this project'))
+      end
+
+      def error_no_license
+        error(_('Your license does not support on-call schedules'))
+      end
+    end
+  end
+end

ee/spec/services/incident_management/oncall_schedules/update_service_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe IncidentManagement::OncallSchedules::UpdateService do
+  let_it_be(:user_with_permissions) { create(:user) }
+  let_it_be(:user_without_permissions) { create(:user) }
+  let_it_be_with_refind(:project) { create(:project) }
+  let!(:oncall_schedule) { create(:incident_management_oncall_schedule, project: project) }
+
+  let(:current_user) { user_with_permissions }
+  let(:params) { { name: 'Updated name', description: 'Updated description', timezone: 'America/New_York' } }
+  let(:service) { described_class.new(oncall_schedule, current_user, params) }
+
+  before do
+    stub_licensed_features(oncall_schedules: true)
+    project.add_maintainer(user_with_permissions)
+  end
+
+  describe '#execute' do
+    shared_examples 'error response' do |message|
+      it 'has an informative message' do
+        expect(execute).to be_error
+        expect(execute.message).to eq(message)
+      end
+    end
+
+    subject(:execute) { service.execute }
+
+    context 'when the current_user is anonymous' do
+      let(:current_user) { nil }
+
+      it_behaves_like 'error response', 'You have insufficient permissions to update an on-call schedule for this project'
+    end
+
+    context 'when the current_user does not have permissions to update on-call schedules' do
+      let(:current_user) { user_without_permissions }
+
+      it_behaves_like 'error response', 'You have insufficient permissions to update an on-call schedule for this project'
+    end
+
+    context 'when feature is not available' do
+      before do
+        stub_licensed_features(oncall_schedules: false)
+      end
+
+      it_behaves_like 'error response', 'Your license does not support on-call schedules'
+    end
+
+    context 'when feature flag is disabled' do
+      before do
+        stub_feature_flags(oncall_schedules_mvc: false)
+      end
+
+      it_behaves_like 'error response', 'Your license does not support on-call schedules'
+    end
+
+    context 'when an on-call schedule witht the same name already exists' do
+      before do
+        create(:incident_management_oncall_schedule, project: project, name: params[:name])
+      end
+
+      it_behaves_like 'error response', 'Name has already been taken'
+    end
+
+    context 'with valid params' do
+      it 'successfully creates an on-call schedule' do
+        response = execute
+        payload = response.payload
+        oncall_schedule.reload
+
+        expect(response).to be_success
+        expect(payload[:oncall_schedule]).to eq(oncall_schedule)
+        expect(oncall_schedule).to be_a(::IncidentManagement::OncallSchedule)
+        expect(oncall_schedule.name).to eq(params[:name])
+        expect(oncall_schedule.description).to eq(params[:description])
+        expect(oncall_schedule.timezone).to eq(params[:timezone])
+      end
+    end
+  end
+end