Move requirements into its own module

Because there will be multiple resources needed for requirements
it's better to keep them all together in a separate module.

requirements table is not renamed because renaming this would cause
downtime and deployment issues.

ee/app/finders/requirements_finder.rb

@@ -26,7 +26,7 @@ class RequirementsFinder
   attr_reader :current_user, :params
 
   def init_collection
-    return Requirement.none unless Ability.allowed?(current_user, :read_requirement, project)
+    return RequirementsManagement::Requirement.none unless Ability.allowed?(current_user, :read_requirement, project)
 
     project.requirements
   end
@@ -50,7 +50,7 @@ class RequirementsFinder
   end
 
   def sort(items)
-    sorts = Requirement.simple_sorts.keys
+    sorts = RequirementsManagement::Requirement.simple_sorts.keys
     sort = sorts.include?(params[:sort]) ? params[:sort] : 'id_desc'
 
     items.order_by(sort)

ee/app/graphql/resolvers/requirements_resolver.rb

@@ -25,8 +25,8 @@ module Resolvers
       # At this point we need the `id` of the project to query for issues, so
       # make sure it's loaded and not `nil` before continuing.
       project = object.respond_to?(:sync) ? object.sync : object
-      return Requirement.none if project.nil?
-      return Requirement.none unless Feature.enabled?(:requirements_management, project, default_enabled: true)
+      return RequirementsManagement::Requirement.none if project.nil?
+      return RequirementsManagement::Requirement.none unless Feature.enabled?(:requirements_management, project, default_enabled: true)
 
       args[:project_id] = project.id
       args[:iids] ||= [args[:iid]].compact

ee/app/models/ee/project.rb

@@ -59,7 +59,7 @@ module EE
       has_many :audit_events, as: :entity
       has_many :designs, inverse_of: :project, class_name: 'DesignManagement::Design'
       has_many :path_locks
-      has_many :requirements
+      has_many :requirements, inverse_of: :project, class_name: 'RequirementsManagement::Requirement'
 
       # the rationale behind vulnerabilities and vulnerability_findings can be found here:
       # https://gitlab.com/gitlab-org/gitlab/issues/10252#terminology

ee/app/models/ee/user.rb

@@ -34,7 +34,7 @@ module EE
 
       has_many :reviews,                  foreign_key: :author_id, inverse_of: :author
       has_many :epics,                    foreign_key: :author_id
-      has_many :requirements,             foreign_key: :author_id
+      has_many :requirements,             foreign_key: :author_id, inverse_of: :author, class_name: 'RequirementsManagement::Requirement'
       has_many :assigned_epics,           foreign_key: :assignee_id, class_name: "Epic"
       has_many :path_locks,               dependent: :destroy # rubocop: disable Cop/ActiveRecordDependent
       has_many :vulnerability_feedback, foreign_key: :author_id, class_name: 'Vulnerabilities::Feedback'

ee/app/models/requirement.rb

-# frozen_string_literal: true
-
-class Requirement < ApplicationRecord
-  include CacheMarkdownField
-  include StripAttribute
-  include AtomicInternalId
-  include Sortable
-
-  cache_markdown_field :title, pipeline: :single_line
-
-  strip_attributes :title
-
-  belongs_to :author, class_name: 'User'
-  belongs_to :project
-
-  has_internal_id :iid, scope: :project, init: ->(s) { s&.project&.requirements&.maximum(:iid) }
-
-  validates :author, :project, :title, presence: true
-
-  validates :title, length: { maximum: Issuable::TITLE_LENGTH_MAX }
-  validates :title_html, length: { maximum: Issuable::TITLE_HTML_LENGTH_MAX }, allow_blank: true
-
-  enum state: { opened: 1, archived: 2 }
-
-  scope :for_iid, -> (iid) { where(iid: iid) }
-  scope :for_state, -> (state) { where(state: state) }
-  scope :counts_by_state, -> { group(:state).count }
-
-  def self.simple_sorts
-    super.except('name_asc', 'name_desc')
-  end
-
-  # In the next iteration we will support also group-level requirements
-  # so it's better to use resource_parent instead of project directly
-  def resource_parent
-    project
-  end
-end

ee/app/models/requirements_management/requirement.rb

+# frozen_string_literal: true
+
+module RequirementsManagement
+  class Requirement < ApplicationRecord
+    include CacheMarkdownField
+    include StripAttribute
+    include AtomicInternalId
+    include Sortable
+
+    # the expected name for this table is `requirements_management_requirements`,
+    # but to avoid downtime and deployment issues `requirements` is still used
+    # https://gitlab.com/gitlab-org/gitlab/-/merge_requests/30052#note_329556542
+    self.table_name = 'requirements'
+
+    cache_markdown_field :title, pipeline: :single_line
+
+    strip_attributes :title
+
+    belongs_to :author, inverse_of: :requirements, class_name: 'User'
+    belongs_to :project, inverse_of: :requirements
+
+    has_internal_id :iid, scope: :project, init: ->(s) { s&.project&.requirements&.maximum(:iid) }
+
+    validates :author, :project, :title, presence: true
+
+    validates :title, length: { maximum: Issuable::TITLE_LENGTH_MAX }
+    validates :title_html, length: { maximum: Issuable::TITLE_HTML_LENGTH_MAX }, allow_blank: true
+
+    enum state: { opened: 1, archived: 2 }
+
+    scope :for_iid, -> (iid) { where(iid: iid) }
+    scope :for_state, -> (state) { where(state: state) }
+    scope :counts_by_state, -> { group(:state).count }
+
+    def self.simple_sorts
+      super.except('name_asc', 'name_desc')
+    end
+
+    # In the next iteration we will support also group-level requirements
+    # so it's better to use resource_parent instead of project directly
+    def resource_parent
+      project
+    end
+  end
+end

ee/app/policies/requirement_policy.rb

-# frozen_string_literal: true
-
-class RequirementPolicy < BasePolicy
-  delegate { @subject.resource_parent }
-end

ee/app/policies/requirements_management/requirement_policy.rb

+# frozen_string_literal: true
+
+module RequirementsManagement
+  class RequirementPolicy < BasePolicy
+    delegate { @subject.resource_parent }
+  end
+end

ee/app/services/ee/users/migrate_to_ghost_user_service.rb

@@ -7,7 +7,7 @@ module EE
 
       def migrate_records
         migrate_epics
-        migrate_requirements
+        migrate_requirements_management_requirements
         migrate_vulnerabilities_feedback
         migrate_reviews
         super
@@ -20,7 +20,7 @@ module EE
       end
       # rubocop: enable CodeReuse/ActiveRecord
 
-      def migrate_requirements
+      def migrate_requirements_management_requirements
         user.requirements.update_all(author_id: ghost_user.id)
       end
 

ee/spec/factories/requirements.rb → ee/spec/factories/requirements_management/requirements.rb

 # frozen_string_literal: true
 
 FactoryBot.define do
-  factory :requirement do
+  factory :requirement, class: 'RequirementsManagement::Requirement' do
     project
     author
     title { generate(:title) }

ee/spec/models/requirement_spec.rb → ee/spec/models/requirements_management/requirement_spec.rb

@@ -2,7 +2,7 @@
 
 require 'spec_helper'
 
-describe Requirement do
+describe RequirementsManagement::Requirement do
   let_it_be(:user) { create(:user) }
   let_it_be(:project) { create(:project) }
 

ee/spec/policies/requirement_policy_spec.rb → ee/spec/policies/requirements_management/requirement_policy_spec.rb

@@ -2,7 +2,7 @@
 
 require 'spec_helper'
 
-describe RequirementPolicy do
+describe RequirementsManagement::RequirementPolicy do
   let_it_be(:owner) { create(:user) }
   let_it_be(:admin) { create(:admin) }
   let_it_be(:reporter) { create(:user) }

ee/spec/requests/api/graphql/mutations/requirements/create_spec.rb

@@ -29,7 +29,7 @@ describe 'Creating a Requirement' do
                'or you don\'t have permission to perform this action']
 
     it 'does not create requirement' do
-      expect { post_graphql_mutation(mutation, current_user: current_user) }.not_to change(Requirement, :count)
+      expect { post_graphql_mutation(mutation, current_user: current_user) }.not_to change(RequirementsManagement::Requirement, :count)
     end
   end
 
@@ -69,7 +69,7 @@ describe 'Creating a Requirement' do
           errors: ["Title can't be blank"]
 
         it 'does not create the requirement' do
-          expect { post_graphql_mutation(mutation, current_user: current_user) }.not_to change(Requirement, :count)
+          expect { post_graphql_mutation(mutation, current_user: current_user) }.not_to change(RequirementsManagement::Requirement, :count)
         end
       end
 

ee/spec/services/ee/users/migrate_to_ghost_user_service_spec.rb

@@ -53,7 +53,7 @@ describe Users::MigrateToGhostUserService do
     let!(:user)   { create(:user) }
     let(:service) { described_class.new(user) }
 
-    include_examples "migrating a deleted user's associated records to the ghost user", Requirement, [:author] do
+    include_examples "migrating a deleted user's associated records to the ghost user", RequirementsManagement::Requirement, [:author] do
       let(:created_record) { create(:requirement, author: user) }
     end
   end

ee/spec/services/requirements/create_service_spec.rb

@@ -21,7 +21,7 @@ describe Requirements::CreateService do
       end
 
       it 'creates new requirement' do
-        expect { subject }.to change { Requirement.count }.by(1)
+        expect { subject }.to change { RequirementsManagement::Requirement.count }.by(1)
       end
 
       it 'uses only permitted params' do