Incremental backup: accept GTID position without 'MySQL56/' flavor prefix

go/mysql/replication_position.go

@@ -145,6 +145,25 @@ func DecodePosition(s string) (rp Position, err error) {
  return ParsePosition(flav, gtid)
 }
 
+// DecodePositionDefaultFlavor converts a string in the format returned by
+// EncodePosition back into a Position value with the
+// correct underlying flavor. If the string does not indicate a flavor, then the 'flavor' argument
+// is used. For example:
+// - DecodePositionDefaultFlavor("MySQL56/16b1039f-22b6-11ed-b765-0a43f95f28a3:1-615", "foo"): "MySQL56" explicitly indicated, this is the flavor.
+// - DecodePositionDefaultFlavor("16b1039f-22b6-11ed-b765-0a43f95f28a3:1-615", "MySQL56"): No flavor indicated in `s`, therefore using "MySQL56"
+func DecodePositionDefaultFlavor(s string, flavor string) (rp Position, err error) {
+ if s == "" {
+ return rp, nil
+ }
+
+ flav, gtid, ok := strings.Cut(s, "/")
+ if !ok {
+ gtid = s
+ flav = flavor
+ }
+ return ParsePosition(flav, gtid)
+}
+
 // ParsePosition calls the parser for the specified flavor.
 func ParsePosition(flavor, value string) (rp Position, err error) {
  parser := gtidSetParsers[flavor]

go/mysql/replication_position_test.go

@@ -272,6 +272,24 @@ func TestDecodePosition(t *testing.T) {
 
 }
 
+func TestDecodePositionDefaultFlavor(t *testing.T) {
+ gtidSetParsers[Mysql56FlavorID] = func(s string) (GTIDSet, error) {
+ return ParseMysql56GTIDSet(s)
+ }
+ {
+ pos := "MySQL56/16b1039f-22b6-11ed-b765-0a43f95f28a3:1-615"
+ rp, err := DecodePositionDefaultFlavor(pos, "foo")
+ assert.NoError(t, err)
+ assert.Equal(t, "16b1039f-22b6-11ed-b765-0a43f95f28a3:1-615", rp.GTIDSet.String())
+ }
+ {
+ pos := "16b1039f-22b6-11ed-b765-0a43f95f28a3:1-615"
+ rp, err := DecodePositionDefaultFlavor(pos, Mysql56FlavorID)
+ assert.NoError(t, err)
+ assert.Equal(t, "16b1039f-22b6-11ed-b765-0a43f95f28a3:1-615", rp.GTIDSet.String())
+ }
+}
+
 func TestDecodePositionZero(t *testing.T) {
  input := ""
  want := Position{}

go/vt/mysqlctl/builtinbackupengine.go

@@ -208,6 +208,22 @@ func (be *BuiltinBackupEngine) ExecuteBackup(ctx context.Context, params BackupP
  return be.executeFullBackup(ctx, params, bh)
 }
 
+// getIncrementalFromPosGTIDSet turns the given string into a valid Mysql56GTIDSet
+func getIncrementalFromPosGTIDSet(incrementalFromPos string) (mysql.Mysql56GTIDSet, error) {
+ pos, err := mysql.DecodePositionDefaultFlavor(incrementalFromPos, mysql.Mysql56FlavorID)
+ if err != nil {
+ return nil, vterrors.Wrapf(err, "cannot decode position in incremental backup: %v", incrementalFromPos)
+ }
+ if !pos.MatchesFlavor(mysql.Mysql56FlavorID) {
+ return nil, vterrors.Errorf(vtrpc.Code_FAILED_PRECONDITION, "incremental backup only supports MySQL GTID positions. Got: %v", incrementalFromPos)
+ }
+ ifPosGTIDSet, ok := pos.GTIDSet.(mysql.Mysql56GTIDSet)
+ if !ok {
+ return nil, vterrors.Errorf(vtrpc.Code_FAILED_PRECONDITION, "cannot get MySQL GTID value: %v", pos)
+ }
+ return ifPosGTIDSet, nil
+}
+
 // executeIncrementalBackup runs an incremental backup, based on given 'incremental_from_pos', which can be:
 // - A valid position
 // - "auto", indicating the incremental backup should begin with last successful backup end position.
@@ -259,21 +275,7 @@ func (be *BuiltinBackupEngine) executeIncrementalBackup(ctx context.Context, par
  }
 
  // params.IncrementalFromPos is a string. We want to turn that into a MySQL GTID
- getIncrementalFromPosGTIDSet := func() (mysql.Mysql56GTIDSet, error) {
- pos, err := mysql.DecodePosition(params.IncrementalFromPos)
- if err != nil {
- return nil, vterrors.Wrapf(err, "cannot decode position in incremental backup: %v", params.IncrementalFromPos)
- }
- if !pos.MatchesFlavor(mysql.Mysql56FlavorID) {
- return nil, vterrors.Errorf(vtrpc.Code_FAILED_PRECONDITION, "incremental backup only supports MySQL GTID positions. Got: %v", params.IncrementalFromPos)
- }
- ifPosGTIDSet, ok := pos.GTIDSet.(mysql.Mysql56GTIDSet)
- if !ok {
- return nil, vterrors.Errorf(vtrpc.Code_FAILED_PRECONDITION, "cannot get MySQL GTID value: %v", pos)
- }
- return ifPosGTIDSet, nil
- }
- backupFromGTIDSet, err := getIncrementalFromPosGTIDSet()
+ backupFromGTIDSet, err := getIncrementalFromPosGTIDSet(params.IncrementalFromPos)
  if err != nil {
  return false, err
  }

go/vt/mysqlctl/builtinbackupengine2_test.go

@@ -0,0 +1,69 @@
+/*
+Copyright 2023 The Vitess Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package mysqlctl_test is the blackbox tests for package mysqlctl.
+package mysqlctl
+
+import (
+ "testing"
+
+ "github.com/stretchr/testify/assert"
+)
+
+func TestGetIncrementalFromPosGTIDSet(t *testing.T) {
+ tcases := []struct {
+ incrementalFromPos string
+ gtidSet string
+ expctError bool
+ }{
+ {
+ "MySQL56/16b1039f-22b6-11ed-b765-0a43f95f28a3:1-615",
+ "16b1039f-22b6-11ed-b765-0a43f95f28a3:1-615",
+ false,
+ },
+ {
+ "16b1039f-22b6-11ed-b765-0a43f95f28a3:1-615",
+ "16b1039f-22b6-11ed-b765-0a43f95f28a3:1-615",
+ false,
+ },
+ {
+ "MySQL56/16b1039f-22b6-11ed-b765-0a43f95f28a3",
+ "",
+ true,
+ },
+ {
+ "MySQL56/invalid",
+ "",
+ true,
+ },
+ {
+ "16b1039f-22b6-11ed-b765-0a43f95f28a3",
+ "",
+ true,
+ },
+ }
+ for _, tcase := range tcases {
+ t.Run(tcase.incrementalFromPos, func(t *testing.T) {
+ gtidSet, err := getIncrementalFromPosGTIDSet(tcase.incrementalFromPos)
+ if tcase.expctError {
+ assert.Error(t, err)
+ } else {
+ assert.NoError(t, err)
+ assert.Equal(t, tcase.gtidSet, gtidSet.String())
+ }
+ })
+ }
+}