Bug Report: Flavor is required in GTID position for incremental restore-to-position value

[mattlord]

Overview of the Issue

We intended to remove the need to specify the flavor in #13474

The function added there DecodePositionDefaultFlavor(), however, is not used in the call path for the RPC, which ends up here:

vitess/go/vt/vttablet/tabletmanager/restore.go

Lines 239 to 245 in 2078d62

	if request.RestoreToPos != "" {
	pos, err := replication.DecodePosition(request.RestoreToPos)
	if err != nil {
	return vterrors.Wrapf(err, "restore failed: unable to decode --restore-to-pos: %s", request.RestoreToPos)
	}
	params.RestoreToPos = pos
	}

Reproduction Steps

git checkout main && make build

pushd examples/local

./101_initial_cluster.sh

# Generate full backup
vtctldclient BackupShard commerce/0

# Generate a couple of empty incremental backups as there were no writes
# since the full backup.
vtctldclient BackupShard --incremental-from-pos=auto commerce/0
sleep 1
vtctldclient BackupShard --incremental-from-pos=auto commerce/0

# Generate some writes and thus GTIDs.
mysql < ../common/insert_commerce_data.sql

# Save the position we expect to restore to.
RESTORE_POS=${$(mysql 'commerce:0' -sN -e "select @@global.gtid_executed")//\\n/}

# Generate a usable non-empty incremental backup.
vtctldclient BackupShard --incremental-from-pos=auto commerce/0

# Generate one more GTID after the backup.
mysql commerce -e "insert into customer (email) values ('mlord@planetscale.com')"

# Restore the replica to our PIT.
TABLET_ALIAS="$(vtctldclient GetTablets --keyspace commerce --tablet-type replica --shard '0' | awk '{print $1}')"
echo "Restoring tablet ${TABLET_ALIAS} to position ${RESTORE_POS}"
vtctldclient RestoreFromBackup --restore-to-pos "${RESTORE_POS}" "${TABLET_ALIAS}"

sleep 5
echo -e "\nAttempting restore using position with the Flavor added\n"

# Restore using adjusted POS with Flavor.
RESTORE_POS="MySQL56/${RESTORE_POS}"
echo "Restoring tablet ${TABLET_ALIAS} to position ${RESTORE_POS}"
vtctldclient RestoreFromBackup --restore-to-pos "${RESTORE_POS}" "${TABLET_ALIAS}"

./401_teardown.sh

popd

Binary Version

vtgate version Version: 20.0.0-SNAPSHOT (Git revision 308f1fc5f0feac229f817bb30ef3b6fd0fe1fca9 branch 'main') built on Thu Mar 28 13:07:27 EDT 2024 by matt@pslord.local using go1.22.1 darwin/arm64

Operating System and Environment details

N/A

Log Fragments

No response

[shlomi-noach]

Solved in #15599