From df127e042ffa0409857c8a7e5e35dd9144805af8 Mon Sep 17 00:00:00 2001
From: Minghui Yang <myang@yugabyte.com>
Date: Thu, 16 May 2024 23:03:18 +0000
Subject: [PATCH] [#13358] YSQL: YBDdlAtomicityBackupTest::RunDdlAtomicityTest
 test change

Summary:
The way the test YBDdlAtomicityBackupTest::RunDdlAtomicityTest is written, all
the DDLs will be inflight during the backup - so backup will fail. It's better
to test the case where backup fails if any single DDL is inflight. This diff
changes the test to randomly pick one DDL to be inflight and verify the backup
fails.
Jira: DB-2996

Test Plan:
./yb_build.sh release --cxx-test yb-backup-cross-feature-test --gtest_filter YBDdlAtomicityBackupTest.DdlRollbackAtomicityTest  -n 20

Reviewers: fizaa

Reviewed By: fizaa

Subscribers: ybase, yql

Differential Revision: https://phorge.dev.yugabyte.com/D35140
---
 src/yb/tools/yb-backup/yb-backup-cross-feature-test.cc | 5 +++--
 src/yb/yql/pgwrapper/pg_ddl_atomicity_test_base.cc     | 9 +++++++++
 src/yb/yql/pgwrapper/pg_ddl_atomicity_test_base.h      | 4 ++++
 3 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/src/yb/tools/yb-backup/yb-backup-cross-feature-test.cc b/src/yb/tools/yb-backup/yb-backup-cross-feature-test.cc
index e180b9369586..d94748b09247 100644
--- a/src/yb/tools/yb-backup/yb-backup-cross-feature-test.cc
+++ b/src/yb/tools/yb-backup/yb-backup-cross-feature-test.cc
@@ -1917,12 +1917,13 @@ Status YBDdlAtomicityBackupTest::RunDdlAtomicityTest(pgwrapper::DdlErrorInjectio
 
   auto client = VERIFY_RESULT(cluster_->CreateClient());
 
-  // Run all DDLs after pausing DDL rollback.
   RETURN_NOT_OK(cluster_->SetFlagOnMasters("TEST_pause_ddl_rollback", "true"));
 
   if (inject_error) {
-    RETURN_NOT_OK(RunAllDdlsWithErrorInjection(&conn));
+    // Run one failed DDL after pausing DDL rollback.
+    RETURN_NOT_OK(RunOneDdlWithErrorInjection(&conn));
   } else {
+    // Run all DDLs after pausing DDL rollback.
     RETURN_NOT_OK(RunAllDdls(&conn));
   }
 
diff --git a/src/yb/yql/pgwrapper/pg_ddl_atomicity_test_base.cc b/src/yb/yql/pgwrapper/pg_ddl_atomicity_test_base.cc
index 924e705ae2bb..a1301b74ea00 100644
--- a/src/yb/yql/pgwrapper/pg_ddl_atomicity_test_base.cc
+++ b/src/yb/yql/pgwrapper/pg_ddl_atomicity_test_base.cc
@@ -90,6 +90,15 @@ Status PgDdlAtomicityTestBase::RunAllDdlsWithErrorInjection(PGConn* conn) {
   return Status::OK();
 }
 
+Status PgDdlAtomicityTestBase::RunOneDdlWithErrorInjection(PGConn* conn) {
+  const auto& ddls = GetAllDDLs();
+  const auto selected = RandomUniformInt(0UL, ddls.size() - 1);
+  const auto& ddl = ddls[selected];
+  LOG(INFO) << "selected ddl to fail: " << ddl;
+  RETURN_NOT_OK(conn->TestFailDdl(ddl));
+  return Status::OK();
+}
+
 Status PgDdlAtomicityTestBase::VerifyAllSuccessfulDdls(PGConn *conn,
                                                        client::YBClient* client,
                                                        const string& database) {
diff --git a/src/yb/yql/pgwrapper/pg_ddl_atomicity_test_base.h b/src/yb/yql/pgwrapper/pg_ddl_atomicity_test_base.h
index 959cabc29280..5ed0a51a1ae7 100644
--- a/src/yb/yql/pgwrapper/pg_ddl_atomicity_test_base.h
+++ b/src/yb/yql/pgwrapper/pg_ddl_atomicity_test_base.h
@@ -135,6 +135,10 @@ class PgDdlAtomicityTestBase : public LibPqTestBase {
   // initiate rollback on the YB-Master.
   Status RunAllDdlsWithErrorInjection(PGConn* conn);
 
+  // From all possible DDLs supported by this test, randomly select one DDL and run with
+  // error injection. The selected DDL will fail and initiate rollback on the YB-Master.
+  Status RunOneDdlWithErrorInjection(PGConn* conn);
+
   // API that can be used after 'RunAllDdls' above to wait for all the DDL verification to
   // complete.
   Status WaitForDdlVerificationAfterSuccessfulDdl(