restore: precheck cluster is empty when first time full restore (#45014…

…) (#58774)

close #35744

br/cmd/br/restore.go

@@ -72,12 +72,12 @@ func printWorkaroundOnFullRestoreError(command *cobra.Command, err error) {
 	fmt.Println("#######################################################################")
 	switch {
 	case errors.ErrorEqual(err, berrors.ErrRestoreNotFreshCluster):
-		fmt.Println("# the target cluster is not fresh, br cannot restore system tables.")
+		fmt.Println("# the target cluster is not fresh, cannot restore.")
+		fmt.Println("# you can drop existing databases and tables and start restore again")
 	case errors.ErrorEqual(err, berrors.ErrRestoreIncompatibleSys):
 		fmt.Println("# the target cluster is not compatible with the backup data,")
-		fmt.Println("# br cannot restore system tables.")
+		fmt.Println("# you can remove 'with-sys-table' flag to skip restoring system tables")
 	}
-	fmt.Println("# you can remove 'with-sys-table' flag to skip restoring system tables")
 	fmt.Println("#######################################################################")
 }
 

br/pkg/backup/push.go

@@ -130,7 +130,7 @@ func (push *pushDown) pushBackup(
 			}
 			failpoint.Inject("backup-timeout-error", func(val failpoint.Value) {
 				msg := val.(string)
-				logutil.CL(ctx).Debug("failpoint backup-timeout-error injected.", zap.String("msg", msg))
+				logutil.CL(ctx).Info("failpoint backup-timeout-error injected.", zap.String("msg", msg))
 				resp.Error = &backuppb.Error{
 					Msg: msg,
 				}

br/pkg/restore/client.go

@@ -1756,6 +1756,11 @@ func (rc *Client) IsFull() bool {
 	return !rc.IsIncremental()
 }
 
+// NeedCheckFreshCluster is every time. except user has not set filter argument.
+func (rc *Client) NeedCheckFreshCluster(ExplicitFilter bool) bool {
+	return rc.IsFull() && !ExplicitFilter
+}
+
 // IsIncremental returns whether this backup is incremental.
 func (rc *Client) IsIncremental() bool {
 	return !(rc.backupMeta.StartVersion == rc.backupMeta.EndVersion ||

br/pkg/task/restore.go

@@ -613,17 +613,22 @@ func runRestore(c context.Context, g glue.Glue, cmdName string, cfg *RestoreConf
 		return errors.Trace(err)
 	}
 
-	// todo: move this check into InitFullClusterRestore, we should move restore config into a separate package
-	// to avoid import cycle problem which we won't do it in this pr, then refactor this
-	//
-	// if it's point restore and reached here, then cmdName=FullRestoreCmd and len(cfg.FullBackupStorage) > 0
-	if cmdName == FullRestoreCmd && cfg.WithSysTable {
-		client.InitFullClusterRestore(cfg.ExplicitFilter)
+	if isFullRestore(cmdName) {
+		if client.NeedCheckFreshCluster(cfg.ExplicitFilter) {
+			if err = client.CheckTargetClusterFresh(ctx); err != nil {
+				return errors.Trace(err)
+			}
+		}
+		// todo: move this check into InitFullClusterRestore, we should move restore config into a separate package
+		// to avoid import cycle problem which we won't do it in this pr, then refactor this
+		//
+		// if it's point restore and reached here, then cmdName=FullRestoreCmd and len(cfg.FullBackupStorage) > 0
+		if cfg.WithSysTable {
+			client.InitFullClusterRestore(cfg.ExplicitFilter)
+		}
 	}
+
 	if client.IsFullClusterRestore() && client.HasBackedUpSysDB() {
-		if err = client.CheckTargetClusterFresh(ctx); err != nil {
-			return errors.Trace(err)
-		}
 		if err = client.CheckSysTableCompatibility(mgr.GetDomain(), tables); err != nil {
 			return errors.Trace(err)
 		}

br/tests/br_backup_empty/run.sh

@@ -48,6 +48,7 @@ if [ $? -ne 0 ]; then
     exit 1
 fi
 
+i=1
 while [ $i -le $DB_COUNT ]; do
     run_sql "DROP DATABASE $DB$i;"
     i=$(($i+1))
@@ -71,6 +72,7 @@ run_sql "CREATE TABLE ${DB}1.usertable1 ( \
 echo "backup empty table start..."
 run_br --pd $PD_ADDR backup full -s "local://$TEST_DIR/empty_table"
 
+i=1
 while [ $i -le $DB_COUNT ]; do
     run_sql "DROP DATABASE $DB$i;"
     i=$(($i+1))
@@ -83,6 +85,7 @@ run_br --pd $PD_ADDR restore full -s "local://$TEST_DIR/empty_table"
 # insert one row to make sure table is restored.
 run_sql "INSERT INTO ${DB}1.usertable1 VALUES (\"a\", \"b\");"
 
+i=1
 while [ $i -le $DB_COUNT ]; do
     run_sql "DROP DATABASE $DB$i;"
     i=$(($i+1))

br/tests/br_file_corruption/run.sh

@@ -46,6 +46,7 @@ if [ $restore_fail -ne 1 ]; then
     exit 1
 fi
 run_sql "DROP DATABASE IF EXISTS $DB;"
+run_sql "DROP DATABASE __tidb_br_temporary_mysql;"
 
 # file corruption
 for filename in $(find $TEST_DIR/$DB -name "*.sst_temp"); do
@@ -62,6 +63,7 @@ if [ $restore_fail -ne 1 ]; then
     exit 1
 fi
 run_sql "DROP DATABASE IF EXISTS $DB;"
+run_sql "DROP DATABASE __tidb_br_temporary_mysql;"
 
 # verify validating checksum is still performed even backup didn't enable it
 for filename in $(find $TEST_DIR/$DB -name "*.sst_bak"); do
@@ -77,6 +79,7 @@ if [ $restore_fail -ne 1 ]; then
     exit 1
 fi
 run_sql "DROP DATABASE IF EXISTS $DB;"
+run_sql "DROP DATABASE __tidb_br_temporary_mysql;"
 
 # sanity check restore can succeed
 run_br --pd $PD_ADDR restore full -s "local://$TEST_DIR/$DB" --checksum=true

br/tests/br_full_ddl/run.sh

@@ -153,6 +153,7 @@ fi
 
 # clear restore environment
 run_sql "DROP DATABASE $DB;"
+run_sql "DROP DATABASE __tidb_br_temporary_mysql;"
 # restore full
 echo "restore start..."
 export GO_FAILPOINTS="github.com/pingcap/tidb/br/pkg/pdutil/PDEnabledPauseConfig=return(true)"

br/tests/br_systables/run.sh

@@ -42,7 +42,7 @@ add_test_data() {
 }
 
 delete_test_data() {
-    run_sql "DROP TABLE usertest.test;"
+    run_sql "DROP DATABASE usertest;"
 }
 
 rollback_modify() {