Merge branch '396351-no-ddl-transaction-for-batch-migrations' into 'master'

Require disable_ddl_transaction on bbm finalization

See merge request gitlab-org/gitlab!114558



Merged-by: Pavel Shutsin <pshutsin@gitlab.com>
Approved-by: Pavel Shutsin <pshutsin@gitlab.com>
Co-authored-by: Marius Bobin <mbobin@gitlab.com>

db/post_migrate/20230228021910_ensure_timelogs_note_id_bigint_backfill_is_finished_for_gitlab_dot_com.rb

@@ -2,6 +2,7 @@
 
 class EnsureTimelogsNoteIdBigintBackfillIsFinishedForGitlabDotCom < Gitlab::Database::Migration[2.1]
   restrict_gitlab_migration gitlab_schema: :gitlab_main
+  disable_ddl_transaction!
 
   def up
     return unless should_run?

lib/gitlab/database/migrations/batched_background_migration_helpers.rb

@@ -201,6 +201,12 @@ def gitlab_schema_from_context
         def ensure_batched_background_migration_is_finished(job_class_name:, table_name:, column_name:, job_arguments:, finalize: true)
           Gitlab::Database::QueryAnalyzers::RestrictAllowedSchemas.require_dml_mode!
 
+          if transaction_open?
+            raise 'The `ensure_batched_background_migration_is_finished` cannot be run inside a transaction. ' \
+              'You can disable transactions by calling `disable_ddl_transaction!` in the body of ' \
+              'your migration class.'
+          end
+
           Gitlab::Database::BackgroundMigration::BatchedMigration.reset_column_information
           migration = Gitlab::Database::BackgroundMigration::BatchedMigration.find_for_configuration(
             Gitlab::Database.gitlab_schemas_for_connection(connection),

spec/lib/gitlab/database/migrations/batched_background_migration_helpers_spec.rb

@@ -513,6 +513,17 @@ def self.name
       end
     end
 
+    context 'when within transaction' do
+      before do
+        allow(migration).to receive(:transaction_open?).and_return(true)
+      end
+
+      it 'does raise an exception' do
+        expect { ensure_batched_background_migration_is_finished }
+          .to raise_error /`ensure_batched_background_migration_is_finished` cannot be run inside a transaction./
+      end
+    end
+
     it 'finalizes the migration' do
       expect(Gitlab::Database::QueryAnalyzers::RestrictAllowedSchemas).to receive(:require_dml_mode!).twice