Update migration to add combination index

- Rename spec vars and tests

db/migrate/20210222030537_add_removed_at_to_oncall_participant.rb → db/migrate/20210222030537_add_is_removed_to_oncall_participant.rb

 # frozen_string_literal: true
 
-class AddRemovedAtToOncallParticipant < ActiveRecord::Migration[6.0]
+class AddIsRemovedToOncallParticipant < ActiveRecord::Migration[6.0]
   include Gitlab::Database::MigrationHelpers
 
   DOWNTIME = false

db/migrate/20210222042745_add_removed_at_to_oncall_participant_index.rb → db/migrate/20210222042745_add_is_removed_index_to_oncall_participant.rb

 # frozen_string_literal: true
 
-class AddRemovedAtToOncallParticipantIndex < ActiveRecord::Migration[6.0]
+class AddIsRemovedIndexToOncallParticipant < ActiveRecord::Migration[6.0]
   include Gitlab::Database::MigrationHelpers
 
   disable_ddl_transaction!
 
   DOWNTIME = false
-  INDEX_NAME = 'index_incident_management_oncall_participants_is_removed'
+  EXISTING_INDEX_NAME = 'index_inc_mgmnt_oncall_participants_on_oncall_rotation_id'
+  NEW_INDEX_NAME = 'index_inc_mgmnt_oncall_pcpnt_on_oncall_rotation_id_is_removed'
 
   def up
-    add_concurrent_index :incident_management_oncall_participants, :is_removed, name: INDEX_NAME
+    add_concurrent_index :incident_management_oncall_participants, [:oncall_rotation_id, :is_removed], name: NEW_INDEX_NAME
+    remove_concurrent_index_by_name(:incident_management_oncall_participants, EXISTING_INDEX_NAME)
   end
 
   def down
-    remove_concurrent_index_by_name(:incident_management_oncall_participants, INDEX_NAME)
+    add_concurrent_index :incident_management_oncall_participants, :oncall_rotation_id, name: EXISTING_INDEX_NAME
+    remove_concurrent_index_by_name(:incident_management_oncall_participants, NEW_INDEX_NAME)
   end
 end

db/structure.sql

@@ -22448,18 +22448,16 @@ CREATE INDEX index_import_failures_on_project_id_not_null ON import_failures USI
 
 CREATE INDEX index_imported_projects_on_import_type_creator_id_created_at ON projects USING btree (import_type, creator_id, created_at) WHERE (import_type IS NOT NULL);
 
-CREATE INDEX index_inc_mgmnt_oncall_participants_on_oncall_rotation_id ON incident_management_oncall_participants USING btree (oncall_rotation_id);
-
 CREATE INDEX index_inc_mgmnt_oncall_participants_on_oncall_user_id ON incident_management_oncall_participants USING btree (user_id);
 
 CREATE UNIQUE INDEX index_inc_mgmnt_oncall_participants_on_user_id_and_rotation_id ON incident_management_oncall_participants USING btree (user_id, oncall_rotation_id);
 
+CREATE INDEX index_inc_mgmnt_oncall_pcpnt_on_oncall_rotation_id_is_removed ON incident_management_oncall_participants USING btree (oncall_rotation_id, is_removed);
+
 CREATE UNIQUE INDEX index_inc_mgmnt_oncall_rotations_on_oncall_schedule_id_and_id ON incident_management_oncall_rotations USING btree (oncall_schedule_id, id);
 
 CREATE UNIQUE INDEX index_inc_mgmnt_oncall_rotations_on_oncall_schedule_id_and_name ON incident_management_oncall_rotations USING btree (oncall_schedule_id, name);
 
-CREATE INDEX index_incident_management_oncall_participants_is_removed ON incident_management_oncall_participants USING btree (is_removed);
-
 CREATE INDEX index_incident_management_oncall_schedules_on_project_id ON incident_management_oncall_schedules USING btree (project_id);
 
 CREATE INDEX index_incident_management_oncall_shifts_on_participant_id ON incident_management_oncall_shifts USING btree (participant_id);

ee/app/models/incident_management/oncall_rotation.rb

@@ -30,8 +30,8 @@ module IncidentManagement
     NAME_LENGTH = 200
 
     belongs_to :schedule, class_name: 'OncallSchedule', inverse_of: 'rotations', foreign_key: 'oncall_schedule_id'
-    # Note! If changing the order of participants, also change the :with_shift_generation_associations scope.
     has_many :participants, -> { order(id: :asc) }, class_name: 'OncallParticipant', inverse_of: :rotation
+    # Note! If changing the order of participants, also change the :with_shift_generation_associations scope.
     has_many :active_participants, -> { not_removed.order(id: :asc) }, class_name: 'OncallParticipant', inverse_of: :rotation
     has_many :users, through: :participants
     has_many :shifts, class_name: 'OncallShift', inverse_of: :rotation, foreign_key: :rotation_id

ee/lib/incident_management/oncall_shift_generator.rb

@@ -175,7 +175,7 @@ module IncidentManagement
 
     def participants
       strong_memoize(:participants) do
-        rotation.participants.not_removed
+        rotation.active_participants
       end
     end
 

ee/spec/models/incident_management/oncall_participant_spec.rb

@@ -40,7 +40,7 @@ RSpec.describe IncidentManagement::OncallParticipant do
   end
 
   describe 'scopes' do
-    let_it_be(:removed) { create(:incident_management_oncall_participant, :removed, rotation: rotation) }
+    let_it_be(:removed_participant) { create(:incident_management_oncall_participant, :removed, rotation: rotation) }
 
     describe '.not_removed' do
       subject { described_class.not_removed }
@@ -51,18 +51,14 @@ RSpec.describe IncidentManagement::OncallParticipant do
     describe '.removed' do
       subject { described_class.removed }
 
-      it { is_expected.to contain_exactly(removed) }
+      it { is_expected.to contain_exactly(removed_participant) }
     end
   end
 
   describe '#mark_as_removed' do
-    around do |example|
-      freeze_time { example.run }
-    end
-
     subject { participant.mark_as_removed }
 
-    it 'updates is_removed to the current time' do
+    it 'updates is_removed to true' do
       expect { subject }.to change { participant.reload.is_removed }.to(true)
     end
   end