Merge branch '293921-wrap-iterations' into 'master'

Wrap current iterations at a group level into an iteration cadence

See merge request gitlab-org/gitlab!50707

app/models/group.rb

@@ -34,6 +34,7 @@ class Group < Namespace
 
   has_many :milestones
   has_many :iterations
+  has_many :iterations_cadences, class_name: 'Iterations::Cadence'
   has_many :services
   has_many :shared_group_links, foreign_key: :shared_with_group_id, class_name: 'GroupGroupLink'
   has_many :shared_with_group_links, foreign_key: :shared_group_id, class_name: 'GroupGroupLink'

app/models/iteration.rb

@@ -16,6 +16,7 @@ class Iteration < ApplicationRecord
 
   belongs_to :project
   belongs_to :group
+  belongs_to :iterations_cadence, class_name: 'Iterations::Cadence', foreign_key: :iterations_cadence_id, inverse_of: :iterations
 
   has_internal_id :iid, scope: :project
   has_internal_id :iid, scope: :group
@@ -26,6 +27,9 @@ class Iteration < ApplicationRecord
   validate :dates_do_not_overlap, if: :start_or_due_dates_changed?
   validate :future_date, if: :start_or_due_dates_changed?, unless: :skip_future_date_validation
   validate :no_project, unless: :skip_project_validation
+  validate :validate_group
+
+  before_create :set_iterations_cadence
 
   scope :upcoming, -> { with_state(:upcoming) }
   scope :started, -> { with_state(:started) }
@@ -135,6 +139,30 @@ class Iteration < ApplicationRecord
 
     errors.add(:project_id, s_("is not allowed. We do not currently support project-level iterations"))
   end
+
+  # TODO: this method should be removed as part of https://gitlab.com/gitlab-org/gitlab/-/issues/296099
+  def set_iterations_cadence
+    return if iterations_cadence
+    # For now we support only group iterations
+    # issue to clarify project iterations: https://gitlab.com/gitlab-org/gitlab/-/issues/299864
+    return unless group
+
+    self.iterations_cadence = group.iterations_cadences.first || create_default_cadence
+  end
+
+  def create_default_cadence
+    cadence_title = "#{group.name} Iterations"
+
+    Iterations::Cadence.create!(group: group, title: cadence_title, start_date: start_date)
+  end
+
+  # TODO: remove this as part of https://gitlab.com/gitlab-org/gitlab/-/issues/296100
+  def validate_group
+    return unless iterations_cadence
+    return if iterations_cadence.group_id == group_id
+
+    errors.add(:group, s_('is not valid. The iteration group has to match the iteration cadence group.'))
+  end
 end
 
 Iteration.prepend_if_ee('EE::Iteration')

app/models/iterations/cadence.rb

+# frozen_string_literal: true
+
+class Iterations::Cadence < ApplicationRecord
+  self.table_name = 'iterations_cadences'
+
+  belongs_to :group
+  has_many :iterations, foreign_key: :iterations_cadence_id, inverse_of: :iterations_cadence
+
+  validates :title, presence: true
+  validates :start_date, presence: true
+  validates :group_id, presence: true
+  validates :active, presence: true
+  validates :automatic, presence: true
+end

changelogs/unreleased/293921-wrap-iterations.yml

+---
+title: Add iterations_cadences table and respective model
+merge_request: 50707
+author:
+type: other

db/migrate/20201228110136_create_iterations_cadence.rb

+# frozen_string_literal: true
+
+class CreateIterationsCadence < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    create_table_with_constraints :iterations_cadences do |t|
+      t.references :group, null: false, foreign_key: { to_table: :namespaces, on_delete: :cascade }
+      t.timestamps_with_timezone null: false
+      t.date :start_date, null: false
+      t.date :last_run_date
+      t.integer :duration_in_weeks
+      t.integer :iterations_in_advance
+      t.boolean :active, default: true, null: false
+      t.boolean :automatic, default: true, null: false
+      t.text :title, null: false
+
+      t.text_limit :title, 255
+    end
+  end
+
+  def down
+    drop_table :iterations_cadences if table_exists?(:iterations_cadences)
+  end
+end

db/migrate/20201228110238_add_iterations_cadence_to_sprints.rb

+# frozen_string_literal: true
+
+class AddIterationsCadenceToSprints < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  INDEX_NAME = 'index_sprints_iterations_cadence_id'
+
+  def up
+    add_column :sprints, :iterations_cadence_id, :integer unless column_exists?(:sprints, :iterations_cadence_id)
+
+    add_concurrent_index :sprints, :iterations_cadence_id, name: INDEX_NAME
+    add_concurrent_foreign_key :sprints, :iterations_cadences, column: :iterations_cadence_id, on_delete: :cascade
+  end
+
+  def down
+    remove_column :sprints, :iterations_cadence_id if column_exists?(:sprints, :iterations_cadence_id)
+  end
+end

db/post_migrate/20201231133921_schedule_set_default_iteration_cadences.rb

+# frozen_string_literal: true
+
+class ScheduleSetDefaultIterationCadences < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+  BATCH_SIZE = 1_000
+  DELAY_INTERVAL = 2.minutes.to_i
+  MIGRATION_CLASS = 'SetDefaultIterationCadences'
+
+  class Iteration < ActiveRecord::Base # rubocop:disable Style/Documentation
+    include EachBatch
+
+    self.table_name = 'sprints'
+  end
+
+  disable_ddl_transaction!
+
+  def up
+    Iteration.select(:group_id).distinct.each_batch(of: BATCH_SIZE, column: :group_id) do |batch, index|
+      group_ids = batch.pluck(:group_id)
+
+      migrate_in(index * DELAY_INTERVAL, MIGRATION_CLASS, group_ids)
+    end
+  end
+
+  def down
+    # Not needed
+  end
+end

db/schema_migrations/20201228110136

+6488e3542276042f302d79533e3e84c43a4ef471535137bcef11e73a0e4d961f
\ No newline at end of file

db/schema_migrations/20201228110238

+7be98c4f62df9fd837f7a547916dd5481c0b4da2d4fc6680b104b2a998be1eed
\ No newline at end of file

db/schema_migrations/20201231133921

+26bf4abb73a53f71fbcb8b5cd1ae1e1539ec59e7052b3bbed95ab1de3fda3de7
\ No newline at end of file

db/structure.sql

@@ -13544,6 +13544,30 @@ CREATE TABLE issues_self_managed_prometheus_alert_events (
     updated_at timestamp with time zone NOT NULL
 );
 
+CREATE TABLE iterations_cadences (
+    id bigint NOT NULL,
+    group_id bigint NOT NULL,
+    created_at timestamp with time zone NOT NULL,
+    updated_at timestamp with time zone NOT NULL,
+    start_date date NOT NULL,
+    last_run_date date,
+    duration_in_weeks integer,
+    iterations_in_advance integer,
+    active boolean DEFAULT true NOT NULL,
+    automatic boolean DEFAULT true NOT NULL,
+    title text NOT NULL,
+    CONSTRAINT check_fedff82d3b CHECK ((char_length(title) <= 255))
+);
+
+CREATE SEQUENCE iterations_cadences_id_seq
+    START WITH 1
+    INCREMENT BY 1
+    NO MINVALUE
+    NO MAXVALUE
+    CACHE 1;
+
+ALTER SEQUENCE iterations_cadences_id_seq OWNED BY iterations_cadences.id;
+
 CREATE TABLE jira_connect_installations (
     id bigint NOT NULL,
     client_key character varying,
@@ -17357,6 +17381,7 @@ CREATE TABLE sprints (
     description text,
     description_html text,
     state_enum smallint DEFAULT 1 NOT NULL,
+    iterations_cadence_id integer,
     CONSTRAINT sprints_must_belong_to_project_or_group CHECK ((((project_id <> NULL::bigint) AND (group_id IS NULL)) OR ((group_id <> NULL::bigint) AND (project_id IS NULL)))),
     CONSTRAINT sprints_title CHECK ((char_length(title) <= 255))
 );
@@ -19068,6 +19093,8 @@ ALTER TABLE ONLY issue_user_mentions ALTER COLUMN id SET DEFAULT nextval('issue_
 
 ALTER TABLE ONLY issues ALTER COLUMN id SET DEFAULT nextval('issues_id_seq'::regclass);
 
+ALTER TABLE ONLY iterations_cadences ALTER COLUMN id SET DEFAULT nextval('iterations_cadences_id_seq'::regclass);
+
 ALTER TABLE ONLY jira_connect_installations ALTER COLUMN id SET DEFAULT nextval('jira_connect_installations_id_seq'::regclass);
 
 ALTER TABLE ONLY jira_connect_subscriptions ALTER COLUMN id SET DEFAULT nextval('jira_connect_subscriptions_id_seq'::regclass);
@@ -20368,6 +20395,9 @@ ALTER TABLE ONLY sprints
 ALTER TABLE ONLY sprints
     ADD CONSTRAINT iteration_start_and_due_daterange_project_id_constraint EXCLUDE USING gist (project_id WITH =, daterange(start_date, due_date, '[]'::text) WITH &&) WHERE ((project_id IS NOT NULL));
 
+ALTER TABLE ONLY iterations_cadences
+    ADD CONSTRAINT iterations_cadences_pkey PRIMARY KEY (id);
+
 ALTER TABLE ONLY jira_connect_installations
     ADD CONSTRAINT jira_connect_installations_pkey PRIMARY KEY (id);
 
@@ -22441,6 +22471,8 @@ CREATE INDEX index_issues_on_updated_at ON issues USING btree (updated_at);
 
 CREATE INDEX index_issues_on_updated_by_id ON issues USING btree (updated_by_id) WHERE (updated_by_id IS NOT NULL);
 
+CREATE INDEX index_iterations_cadences_on_group_id ON iterations_cadences USING btree (group_id);
+
 CREATE UNIQUE INDEX index_jira_connect_installations_on_client_key ON jira_connect_installations USING btree (client_key);
 
 CREATE INDEX index_jira_connect_subscriptions_on_namespace_id ON jira_connect_subscriptions USING btree (namespace_id);
@@ -23431,6 +23463,8 @@ CREATE UNIQUE INDEX index_sop_configs_on_project_id ON security_orchestration_po
 
 CREATE UNIQUE INDEX index_sop_configs_on_security_policy_management_project_id ON security_orchestration_policy_configurations USING btree (security_policy_management_project_id);
 
+CREATE INDEX index_sprints_iterations_cadence_id ON sprints USING btree (iterations_cadence_id);
+
 CREATE INDEX index_sprints_on_description_trigram ON sprints USING gin (description gin_trgm_ops);
 
 CREATE INDEX index_sprints_on_due_date ON sprints USING btree (due_date);
@@ -24268,6 +24302,9 @@ ALTER TABLE ONLY namespaces
 ALTER TABLE ONLY epics
     ADD CONSTRAINT fk_3654b61b03 FOREIGN KEY (author_id) REFERENCES users(id) ON DELETE CASCADE;
 
+ALTER TABLE ONLY sprints
+    ADD CONSTRAINT fk_365d1db505 FOREIGN KEY (iterations_cadence_id) REFERENCES iterations_cadences(id) ON DELETE CASCADE;
+
 ALTER TABLE ONLY push_event_payloads
     ADD CONSTRAINT fk_36c74129da FOREIGN KEY (event_id) REFERENCES events(id) ON DELETE CASCADE;
 
@@ -26143,6 +26180,9 @@ ALTER TABLE ONLY alert_management_alert_user_mentions
 ALTER TABLE ONLY snippet_statistics
     ADD CONSTRAINT fk_rails_ebc283ccf1 FOREIGN KEY (snippet_id) REFERENCES snippets(id) ON DELETE CASCADE;
 
+ALTER TABLE ONLY iterations_cadences
+    ADD CONSTRAINT fk_rails_ece400c55a FOREIGN KEY (group_id) REFERENCES namespaces(id) ON DELETE CASCADE;
+
 ALTER TABLE ONLY dast_profiles
     ADD CONSTRAINT fk_rails_ed1e66fbbf FOREIGN KEY (dast_site_profile_id) REFERENCES dast_site_profiles(id) ON DELETE CASCADE;
 

ee/spec/lib/banzai/filter/iteration_reference_filter_spec.rb

@@ -319,7 +319,9 @@ RSpec.describe Banzai::Filter::IterationReferenceFilter do
       project_reference = another_project.to_reference_base(project)
       input_text = "See #{project_reference}#{reference}"
 
-      iteration.update!(group: another_group)
+      # we have to update iterations_cadence group first in order to avoid invalid record
+      iteration.iterations_cadence.update_column(:group_id, another_group.id)
+      iteration.update_column(:group_id, another_group.id)
 
       doc = reference_filter(input_text)
 
@@ -328,7 +330,9 @@ RSpec.describe Banzai::Filter::IterationReferenceFilter do
     end
 
     it 'supports parent group references' do
-      iteration.update!(group: parent_group)
+      # we have to update iterations_cadence group first in order to avoid invallid record
+      iteration.iterations_cadence.update_column(:group_id, parent_group.id)
+      iteration.update_column(:group_id, parent_group.id)
 
       doc = reference_filter("See #{reference}")
 

lib/gitlab/background_migration/set_default_iteration_cadences.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module BackgroundMigration
+    # rubocop:disable Style/Documentation
+    class SetDefaultIterationCadences
+      class Iteration < ApplicationRecord
+        self.table_name = 'sprints'
+      end
+
+      class IterationCadence < ApplicationRecord
+        self.table_name = 'iterations_cadences'
+
+        include BulkInsertSafe
+      end
+
+      class Group < ApplicationRecord
+        self.table_name = 'namespaces'
+      end
+
+      def perform(*group_ids)
+        create_iterations_cadences(group_ids)
+        assign_iterations_cadences(group_ids)
+      end
+
+      private
+
+      def create_iterations_cadences(group_ids)
+        groups_with_cadence = IterationCadence.select(:group_id)
+        new_cadences = Group.where(id: group_ids).where.not(id: groups_with_cadence).map do |group|
+          last_iteration = Iteration.where(group_id: group.id).order(:start_date)&.last
+
+          next unless last_iteration
+
+          time = Time.now
+          IterationCadence.new(
+            group_id: group.id,
+            title: "#{group.name} Iterations",
+            start_date: last_iteration.start_date,
+            last_run_date: last_iteration.start_date,
+            automatic: false,
+            created_at: time,
+            updated_at: time
+          )
+        end
+
+        IterationCadence.bulk_insert!(new_cadences.compact)
+      end
+
+      def assign_iterations_cadences(group_ids)
+        IterationCadence.where(group_id: group_ids).each do |cadence|
+          Iteration.where(iterations_cadence_id: nil).where(group_id: cadence.group_id).update_all(iterations_cadence_id: cadence.id)
+        end
+      end
+    end
+  end
+end

locale/gitlab.pot

@@ -34933,6 +34933,9 @@ msgstr ""
 msgid "is not in the group enforcing Group Managed Account"
 msgstr ""
 
+msgid "is not valid. The iteration group has to match the iteration cadence group."
+msgstr ""
+
 msgid "is read only"
 msgstr ""
 

spec/factories/iteration_cadences.rb

+# frozen_string_literal: true
+
+FactoryBot.define do
+  sequence(:cadence_sequential_date) do |n|
+    n.days.from_now
+  end
+
+  factory :iterations_cadence, class: 'Iterations::Cadence' do
+    title
+    group
+    start_date { generate(:cadence_sequential_date) }
+  end
+end

spec/lib/gitlab/background_migration/set_default_iteration_cadences_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::BackgroundMigration::SetDefaultIterationCadences, schema: 20201231133921 do
+  let(:namespaces) { table(:namespaces) }
+  let(:iterations) { table(:sprints) }
+  let(:iterations_cadences) { table(:iterations_cadences) }
+
+  describe '#perform' do
+    context 'when no iteration cadences exists' do
+      let!(:group_1) { namespaces.create!(name: 'group 1', path: 'group-1') }
+      let!(:group_2) { namespaces.create!(name: 'group 2', path: 'group-2') }
+      let!(:group_3) { namespaces.create!(name: 'group 3', path: 'group-3') }
+
+      let!(:iteration_1) { iterations.create!(group_id: group_1.id, iid: 1, title: 'Iteration 1', start_date: 10.days.ago, due_date: 8.days.ago) }
+      let!(:iteration_2) { iterations.create!(group_id: group_3.id, iid: 1, title: 'Iteration 2', start_date: 10.days.ago, due_date: 8.days.ago) }
+      let!(:iteration_3) { iterations.create!(group_id: group_3.id, iid: 1, title: 'Iteration 3', start_date: 5.days.ago, due_date: 2.days.ago) }
+
+      before do
+        described_class.new.perform(group_1.id, group_2.id, group_3.id, namespaces.last.id + 1)
+      end
+
+      it 'creates iterations_cadence records for the requested groups' do
+        expect(iterations_cadences.count).to eq(2)
+      end
+
+      it 'assigns the iteration cadences to the iterations correctly' do
+        iterations_cadence = iterations_cadences.find_by(group_id: group_1.id)
+        iteration_records = iterations.where(iterations_cadence_id: iterations_cadence.id)
+
+        expect(iterations_cadence.start_date).to eq(iteration_1.start_date)
+        expect(iterations_cadence.last_run_date).to eq(iteration_1.start_date)
+        expect(iterations_cadence.title).to eq('group 1 Iterations')
+        expect(iteration_records.size).to eq(1)
+        expect(iteration_records.first.id).to eq(iteration_1.id)
+
+        iterations_cadence = iterations_cadences.find_by(group_id: group_3.id)
+        iteration_records = iterations.where(iterations_cadence_id: iterations_cadence.id)
+
+        expect(iterations_cadence.start_date).to eq(iteration_3.start_date)
+        expect(iterations_cadence.last_run_date).to eq(iteration_3.start_date)
+        expect(iterations_cadence.title).to eq('group 3 Iterations')
+        expect(iteration_records.size).to eq(2)
+        expect(iteration_records.first.id).to eq(iteration_2.id)
+        expect(iteration_records.second.id).to eq(iteration_3.id)
+      end
+    end
+
+    context 'when an iteration cadence exists for a group' do
+      let!(:group) { namespaces.create!(name: 'group', path: 'group') }
+
+      let!(:iterations_cadence_1) { iterations_cadences.create!(group_id: group.id, start_date: 5.days.ago, title: 'Cadence 1') }
+      let!(:iterations_cadence_2) { iterations_cadences.create!(group_id: group.id, start_date: 2.days.ago, title: 'Cadence 2') }
+
+      let!(:iteration_1) { iterations.create!(group_id: group.id, iid: 1, title: 'Iteration 1', start_date: 10.days.ago, due_date: 8.days.ago) }
+      let!(:iteration_2) { iterations.create!(group_id: group.id, iterations_cadence_id: iterations_cadence_1.id, iid: 2, title: 'Iteration 2', start_date: 5.days.ago, due_date: 3.days.ago) }
+      let!(:iteration_3) { iterations.create!(group_id: group.id, iterations_cadence_id: iterations_cadence_2.id, iid: 3, title: 'Iteration 3', start_date: 2.days.ago, due_date: 1.day.ago) }
+
+      subject { described_class.new.perform(group.id) }
+
+      it 'does not create a new iterations_cadence' do
+        expect { subject }.not_to change { iterations_cadences.count }
+      end
+
+      it 'assigns iteration cadences to iterations if needed' do
+        subject
+
+        expect(iteration_1.reload.iterations_cadence_id).to eq(iterations_cadence_1.id)
+        expect(iteration_2.reload.iterations_cadence_id).to eq(iterations_cadence_1.id)
+        expect(iteration_3.reload.iterations_cadence_id).to eq(iterations_cadence_2.id)
+      end
+    end
+  end
+end

spec/migrations/schedule_set_default_iteration_cadences_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+require_migration!
+
+RSpec.describe ScheduleSetDefaultIterationCadences do
+  let(:namespaces) { table(:namespaces) }
+  let(:iterations) { table(:sprints) }
+
+  let(:group_1) { namespaces.create!(name: 'test_1', path: 'test_1') }
+  let!(:group_2) { namespaces.create!(name: 'test_2', path: 'test_2') }
+  let(:group_3) { namespaces.create!(name: 'test_3', path: 'test_3') }
+  let(:group_4) { namespaces.create!(name: 'test_4', path: 'test_4') }
+  let(:group_5) { namespaces.create!(name: 'test_5', path: 'test_5') }
+  let(:group_6) { namespaces.create!(name: 'test_6', path: 'test_6') }
+  let(:group_7) { namespaces.create!(name: 'test_7', path: 'test_7') }
+  let(:group_8) { namespaces.create!(name: 'test_8', path: 'test_8') }
+
+  let!(:iteration_1) { iterations.create!(iid: 1, title: 'iteration 1', group_id: group_1.id) }
+  let!(:iteration_2) { iterations.create!(iid: 1, title: 'iteration 2', group_id: group_3.id) }
+  let!(:iteration_3) { iterations.create!(iid: 1, title: 'iteration 2', group_id: group_4.id) }
+  let!(:iteration_4) { iterations.create!(iid: 1, title: 'iteration 2', group_id: group_5.id) }
+  let!(:iteration_5) { iterations.create!(iid: 1, title: 'iteration 2', group_id: group_6.id) }
+  let!(:iteration_6) { iterations.create!(iid: 1, title: 'iteration 2', group_id: group_7.id) }
+  let!(:iteration_7) { iterations.create!(iid: 1, title: 'iteration 2', group_id: group_8.id) }
+
+  around do |example|
+    freeze_time { Sidekiq::Testing.fake! { example.run } }
+  end
+
+  it 'schedules the background jobs', :aggregate_failures do
+    stub_const("#{described_class.name}::BATCH_SIZE", 3)
+
+    migrate!
+
+    expect(BackgroundMigrationWorker.jobs.size).to be(3)
+    expect(described_class::MIGRATION_CLASS).to be_scheduled_delayed_migration(2.minutes, group_1.id, group_3.id, group_4.id)
+    expect(described_class::MIGRATION_CLASS).to be_scheduled_delayed_migration(4.minutes, group_5.id, group_6.id, group_7.id)
+    expect(described_class::MIGRATION_CLASS).to be_scheduled_delayed_migration(6.minutes, group_8.id)
+  end
+end

spec/models/iteration_spec.rb

@@ -5,6 +5,13 @@ require 'spec_helper'
 RSpec.describe Iteration do
   let_it_be(:project) { create(:project) }
   let_it_be(:group) { create(:group) }
+  let(:set_cadence) { nil }
+
+  describe 'associations' do
+    it { is_expected.to belong_to(:project) }
+    it { is_expected.to belong_to(:group) }
+    it { is_expected.to belong_to(:iterations_cadence).inverse_of(:iterations) }
+  end
 
   describe "#iid" do
     it "is properly scoped on project and group" do
@@ -32,6 +39,59 @@ RSpec.describe Iteration do
     end
   end
 
+  describe 'setting iteration cadence' do
+    let_it_be(:iterations_cadence) { create(:iterations_cadence, group: group, start_date: 10.days.ago) }
+    let(:iteration) { create(:iteration, group: group, iterations_cadence: set_cadence, start_date: 2.days.from_now) }
+
+    context 'when iterations_cadence is set correctly' do
+      let(:set_cadence) { iterations_cadence}
+
+      it 'does not change the iterations_cadence' do
+        expect(iteration.iterations_cadence).to eq(iterations_cadence)
+      end
+    end
+
+    context 'when iterations_cadence exists for the group' do
+      let(:set_cadence) { nil }
+
+      it 'sets the iterations_cadence to the existing record' do
+        expect(iteration.iterations_cadence).to eq(iterations_cadence)
+      end
+    end
+
+    context 'when iterations_cadence does not exists for the group' do
+      let_it_be(:group) { create(:group, name: 'Test group')}
+      let(:iteration) { build(:iteration, group: group, iterations_cadence: set_cadence) }
+
+      it 'creates a default iterations_cadence and uses it for the iteration' do
+        expect { iteration.save! }.to change { Iterations::Cadence.count }.by(1)
+      end
+
+      it 'sets the newly created iterations_cadence to the reecord' do
+        iteration.save!
+
+        expect(iteration.iterations_cadence).to eq(Iterations::Cadence.last)
+      end
+
+      it 'creates the iterations_cadence with the correct attributes' do
+        iteration.save!
+
+        cadence = Iterations::Cadence.last
+
+        expect(cadence.reload.start_date).to eq(iteration.start_date)
+        expect(cadence.title).to eq('Test group Iterations')
+      end
+    end
+
+    context 'when iteration is a project iteration' do
+      it 'does not set the iterations_cadence' do
+        iteration = create(:iteration, iterations_cadence: nil, project: project, skip_project_validation: true)
+
+        expect(iteration.reload.iterations_cadence).to be_nil
+      end
+    end
+  end
+
   describe '.filter_by_state' do
     let_it_be(:closed_iteration) { create(:iteration, :closed, :skip_future_date_validation, group: group, start_date: 8.days.ago, due_date: 2.days.ago) }
     let_it_be(:started_iteration) { create(:iteration, :started, :skip_future_date_validation, group: group, start_date: 1.day.ago, due_date: 6.days.from_now) }
@@ -307,6 +367,43 @@ RSpec.describe Iteration do
     end
   end
 
+  describe '#validate_group' do
+    let_it_be(:iterations_cadence) { create(:iterations_cadence, group: group) }
+
+    context 'when the iteration and iteration cadence groups are same' do
+      it 'is valid' do
+        iteration = build(:iteration, group: group, iterations_cadence: iterations_cadence)
+
+        expect(iteration).to be_valid
+      end
+    end
+
+    context 'when the iteration and iteration cadence groups are different' do
+      it 'is invalid' do
+        other_group = create(:group)
+        iteration = build(:iteration, group: other_group, iterations_cadence: iterations_cadence)
+
+        expect(iteration).not_to be_valid
+      end
+    end
+
+    context 'when the iteration belongs to a project and the iteration cadence is set' do
+      it 'is invalid' do
+        iteration = build(:iteration, project: project, iterations_cadence: iterations_cadence, skip_project_validation: true)
+
+        expect(iteration).to be_invalid
+      end
+    end
+
+    context 'when the iteration belongs to a project and the iteration cadence is not set' do
+      it 'is valid' do
+        iteration = build(:iteration, project: project, skip_project_validation: true)
+
+        expect(iteration).to be_valid
+      end
+    end
+  end
+
   describe '.within_timeframe' do
     let_it_be(:now) { Time.current }
     let_it_be(:project) { create(:project, :empty_repo) }

spec/models/iterations/cadence_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Iterations::Cadence do
+  describe 'associations' do
+    subject { build(:iterations_cadence) }
+
+    it { is_expected.to belong_to(:group) }
+    it { is_expected.to have_many(:iterations).inverse_of(:iterations_cadence) }
+  end
+
+  describe 'validations' do
+    subject { build(:iterations_cadence) }
+
+    it { is_expected.to validate_presence_of(:title) }
+    it { is_expected.to validate_presence_of(:start_date) }
+    it { is_expected.to validate_presence_of(:group_id) }
+    it { is_expected.to validate_presence_of(:active) }
+    it { is_expected.to validate_presence_of(:automatic) }
+  end
+end