Remove feature flag check from migration helpers

Remove `database_async_index_creation` feature flag check from
migration helpers related to async index creation.

See https://gitlab.com/gitlab-org/gitlab/-/issues/354776.

lib/gitlab/database/async_indexes/migration_helpers.rb

@@ -72,8 +72,7 @@ module Gitlab
         end
 
         def async_index_creation_available?
-          ApplicationRecord.connection.table_exists?(:postgres_async_indexes) &&
-            Feature.enabled?(:database_async_index_creation, type: :ops)
+          ApplicationRecord.connection.table_exists?(:postgres_async_indexes)
         end
       end
     end

spec/lib/gitlab/database/async_indexes/migration_helpers_spec.rb

@@ -16,45 +16,29 @@ RSpec.describe Gitlab::Database::AsyncIndexes::MigrationHelpers do
   describe '#unprepare_async_index' do
     let!(:async_index) { create(:postgres_async_index, name: index_name) }
 
-    context 'when the flag is enabled' do
-      before do
-        stub_feature_flags(database_async_index_creation: true)
-      end
+    it 'destroys the record' do
+      expect do
+        migration.unprepare_async_index(table_name, 'id')
+      end.to change { index_model.where(name: index_name).count }.by(-1)
+    end
+
+    context 'when an explicit name is given' do
+      let(:index_name) { 'my_test_async_index' }
 
       it 'destroys the record' do
         expect do
-          migration.unprepare_async_index(table_name, 'id')
+          migration.unprepare_async_index(table_name, 'id', name: index_name)
         end.to change { index_model.where(name: index_name).count }.by(-1)
       end
-
-      context 'when an explicit name is given' do
-        let(:index_name) { 'my_test_async_index' }
-
-        it 'destroys the record' do
-          expect do
-            migration.unprepare_async_index(table_name, 'id', name: index_name)
-          end.to change { index_model.where(name: index_name).count }.by(-1)
-        end
-      end
-
-      context 'when the async index table does not exist' do
-        it 'does not raise an error' do
-          connection.drop_table(:postgres_async_indexes)
-
-          expect(index_model).not_to receive(:find_by)
-
-          expect { migration.unprepare_async_index(table_name, 'id') }.not_to raise_error
-        end
-      end
     end
 
-    context 'when the feature flag is disabled' do
-      it 'does not destroy the record' do
-        stub_feature_flags(database_async_index_creation: false)
+    context 'when the async index table does not exist' do
+      it 'does not raise an error' do
+        connection.drop_table(:postgres_async_indexes)
 
-        expect do
-          migration.unprepare_async_index(table_name, 'id')
-        end.not_to change { index_model.where(name: index_name).count }
+        expect(index_model).not_to receive(:find_by)
+
+        expect { migration.unprepare_async_index(table_name, 'id') }.not_to raise_error
       end
     end
   end
@@ -63,35 +47,19 @@ RSpec.describe Gitlab::Database::AsyncIndexes::MigrationHelpers do
     let(:index_name) { "index_#{table_name}_on_id" }
     let!(:async_index) { create(:postgres_async_index, name: index_name) }
 
-    context 'when the flag is enabled' do
-      before do
-        stub_feature_flags(database_async_index_creation: true)
-      end
-
-      it 'destroys the record' do
-        expect do
-          migration.unprepare_async_index_by_name(table_name, index_name)
-        end.to change { index_model.where(name: index_name).count }.by(-1)
-      end
-
-      context 'when the async index table does not exist' do
-        it 'does not raise an error' do
-          connection.drop_table(:postgres_async_indexes)
-
-          expect(index_model).not_to receive(:find_by)
-
-          expect { migration.unprepare_async_index_by_name(table_name, index_name) }.not_to raise_error
-        end
-      end
+    it 'destroys the record' do
+      expect do
+        migration.unprepare_async_index_by_name(table_name, index_name)
+      end.to change { index_model.where(name: index_name).count }.by(-1)
     end
 
-    context 'when the feature flag is disabled' do
-      it 'does not destroy the record' do
-        stub_feature_flags(database_async_index_creation: false)
+    context 'when the async index table does not exist' do
+      it 'does not raise an error' do
+        connection.drop_table(:postgres_async_indexes)
 
-        expect do
-          migration.unprepare_async_index_by_name(table_name, index_name)
-        end.not_to change { index_model.where(name: index_name).count }
+        expect(index_model).not_to receive(:find_by)
+
+        expect { migration.unprepare_async_index_by_name(table_name, index_name) }.not_to raise_error
       end
     end
   end
@@ -101,14 +69,23 @@ RSpec.describe Gitlab::Database::AsyncIndexes::MigrationHelpers do
       connection.create_table(table_name)
     end
 
-    context 'when the feature flag is enabled' do
-      before do
-        stub_feature_flags(database_async_index_creation: true)
-      end
+    it 'creates the record for the async index' do
+      expect do
+        migration.prepare_async_index(table_name, 'id')
+      end.to change { index_model.where(name: index_name).count }.by(1)
+
+      record = index_model.find_by(name: index_name)
 
-      it 'creates the record for the async index' do
+      expect(record.table_name).to eq(table_name)
+      expect(record.definition).to match(/CREATE INDEX CONCURRENTLY "#{index_name}"/)
+    end
+
+    context 'when an explicit name is given' do
+      let(:index_name) { 'my_async_index_name' }
+
+      it 'creates the record with the given name' do
         expect do
-          migration.prepare_async_index(table_name, 'id')
+          migration.prepare_async_index(table_name, 'id', name: index_name)
         end.to change { index_model.where(name: index_name).count }.by(1)
 
         record = index_model.find_by(name: index_name)
@@ -116,77 +93,52 @@ RSpec.describe Gitlab::Database::AsyncIndexes::MigrationHelpers do
         expect(record.table_name).to eq(table_name)
         expect(record.definition).to match(/CREATE INDEX CONCURRENTLY "#{index_name}"/)
       end
+    end
 
-      context 'when an explicit name is given' do
-        let(:index_name) { 'my_async_index_name' }
-
-        it 'creates the record with the given name' do
-          expect do
-            migration.prepare_async_index(table_name, 'id', name: index_name)
-          end.to change { index_model.where(name: index_name).count }.by(1)
-
-          record = index_model.find_by(name: index_name)
+    context 'when the index already exists' do
+      it 'does not create the record' do
+        connection.add_index(table_name, 'id', name: index_name)
 
-          expect(record.table_name).to eq(table_name)
-          expect(record.definition).to match(/CREATE INDEX CONCURRENTLY "#{index_name}"/)
-        end
+        expect do
+          migration.prepare_async_index(table_name, 'id')
+        end.not_to change { index_model.where(name: index_name).count }
       end
+    end
 
-      context 'when the index already exists' do
-        it 'does not create the record' do
-          connection.add_index(table_name, 'id', name: index_name)
+    context 'when the record already exists' do
+      it 'does attempt to create the record' do
+        create(:postgres_async_index, table_name: table_name, name: index_name)
 
-          expect do
-            migration.prepare_async_index(table_name, 'id')
-          end.not_to change { index_model.where(name: index_name).count }
-        end
+        expect do
+          migration.prepare_async_index(table_name, 'id')
+        end.not_to change { index_model.where(name: index_name).count }
       end
 
-      context 'when the record already exists' do
-        it 'does attempt to create the record' do
-          create(:postgres_async_index, table_name: table_name, name: index_name)
-
-          expect do
-            migration.prepare_async_index(table_name, 'id')
-          end.not_to change { index_model.where(name: index_name).count }
-        end
-
-        it 'updates definition if changed' do
-          index = create(:postgres_async_index, table_name: table_name, name: index_name, definition: '...')
-
-          expect do
-            migration.prepare_async_index(table_name, 'id', name: index_name)
-          end.to change { index.reload.definition }
-        end
+      it 'updates definition if changed' do
+        index = create(:postgres_async_index, table_name: table_name, name: index_name, definition: '...')
 
-        it 'does not update definition if not changed' do
-          definition = "CREATE INDEX CONCURRENTLY \"index_#{table_name}_on_id\" ON \"#{table_name}\" (\"id\")"
-          index = create(:postgres_async_index, table_name: table_name, name: index_name, definition: definition)
-
-          expect do
-            migration.prepare_async_index(table_name, 'id', name: index_name)
-          end.not_to change { index.reload.updated_at }
-        end
+        expect do
+          migration.prepare_async_index(table_name, 'id', name: index_name)
+        end.to change { index.reload.definition }
       end
 
-      context 'when the async index table does not exist' do
-        it 'does not raise an error' do
-          connection.drop_table(:postgres_async_indexes)
-
-          expect(index_model).not_to receive(:safe_find_or_create_by!)
+      it 'does not update definition if not changed' do
+        definition = "CREATE INDEX CONCURRENTLY \"index_#{table_name}_on_id\" ON \"#{table_name}\" (\"id\")"
+        index = create(:postgres_async_index, table_name: table_name, name: index_name, definition: definition)
 
-          expect { migration.prepare_async_index(table_name, 'id') }.not_to raise_error
-        end
+        expect do
+          migration.prepare_async_index(table_name, 'id', name: index_name)
+        end.not_to change { index.reload.updated_at }
       end
     end
 
-    context 'when the feature flag is disabled' do
-      it 'does not create the record' do
-        stub_feature_flags(database_async_index_creation: false)
+    context 'when the async index table does not exist' do
+      it 'does not raise an error' do
+        connection.drop_table(:postgres_async_indexes)
 
-        expect do
-          migration.prepare_async_index(table_name, 'id')
-        end.not_to change { index_model.where(name: index_name).count }
+        expect(index_model).not_to receive(:safe_find_or_create_by!)
+
+        expect { migration.prepare_async_index(table_name, 'id') }.not_to raise_error
       end
     end
   end