Create service for assigning policy project

ee/app/services/security/orchestration/assign_service.rb

+# frozen_string_literal: true
+
+module Security
+  module Orchestration
+    class AssignService < ::BaseService
+      def execute
+        res = create_or_update_security_policy_configuration
+
+        return success if res
+
+      rescue ActiveRecord::RecordNotFound => _
+        error('Policy project doesn\'t exists')
+      rescue ActiveRecord::RecordInvalid => _
+        error('Couldn\'t assign policy to project')
+      end
+
+      private
+
+      def create_or_update_security_policy_configuration
+        policy_project = Project.find(policy_project_id)
+
+        if has_existing_policy?
+          project.security_orchestration_policy_configuration.update!(
+            security_policy_management_project_id: policy_project.id
+          )
+        else
+          project.create_security_orchestration_policy_configuration! do |p|
+            p.security_policy_management_project_id = policy_project.id
+          end
+        end
+      end
+
+      def success
+        ServiceResponse.success(payload: { policy_project: policy_project_id })
+      end
+
+      def error(message)
+        ServiceResponse.error(payload: { policy_project: policy_project_id }, message: message)
+      end
+
+      def has_existing_policy?
+        project.security_orchestration_policy_configuration.present?
+      end
+
+      def policy_project_id
+        params[:policy_project_id]
+      end
+    end
+  end
+end

ee/spec/services/security/orchestration/assign_service_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Security::Orchestration::AssignService do
+  let_it_be(:project, reload: true) { create(:project) }
+  let_it_be(:another_project) { create(:project) }
+  let_it_be(:policy_project) { create(:project) }
+  let_it_be(:new_policy_project) { create(:project) }
+
+  describe '#execute' do
+    subject(:service) { described_class.new(project, nil, policy_project_id: policy_project.id).execute }
+
+    it 'assigns policy project to project' do
+      expect(service).to be_success
+      expect(project.security_orchestration_policy_configuration.security_policy_management_project_id).to eq(policy_project.id)
+    end
+
+    it 'updates project with new policy project' do
+      service
+
+      repeated_service = described_class.new(project, nil, policy_project_id: new_policy_project.id).execute
+
+      expect(repeated_service).to be_success
+      expect(project.security_orchestration_policy_configuration.security_policy_management_project_id).to eq(new_policy_project.id)
+    end
+
+    it 'returns error when same policy is assigned to different projects' do
+      service
+
+      repeated_service = described_class.new(another_project, nil, policy_project_id: policy_project.id).execute
+
+      expect(repeated_service).to be_error
+    end
+
+    it 'returns error when db has problem' do
+      dbl_error = double('ActiveRecord')
+      dbl = double('Security::OrchestrationPolicyConfiguration', security_orchestration_policy_configuration: dbl_error)
+
+      allow(dbl_error).to receive(:update!).and_raise(ActiveRecord::RecordInvalid)
+
+      allow_next_instance_of(described_class) do |instance|
+        allow(instance).to receive(:has_existing_policy?).and_return(true)
+        allow(instance).to receive(:project).and_return(dbl)
+      end
+
+      repeated_service = described_class.new(project, nil, policy_project_id: new_policy_project.id).execute
+
+      expect(repeated_service).to be_error
+    end
+
+    describe 'with invalid project id' do
+      subject(:service) { described_class.new(project, nil, policy_project_id: 345).execute }
+
+      it 'assigns policy project to project' do
+        expect(service).to be_error
+
+        expect { service }.not_to change { project.security_orchestration_policy_configuration }
+      end
+    end
+  end
+end