add follower retry option (pingcap#75)

Co-authored-by: artem_danilov <artem_danilov@airbnb.com>

go.mod

@@ -90,8 +90,8 @@ require (
 	github.com/stretchr/testify v1.8.0
 	github.com/tdakkota/asciicheck v0.1.1
 	github.com/tiancaiamao/appdash v0.0.0-20181126055449-889f96f722a2
-        github.com/tikv/client-go/v2 v2.0.4-0.20231020030327-4ecf7c282e37
-        github.com/tikv/pd/client v0.0.0-20230904040343-947701a32c05
+	github.com/tikv/client-go/v2 v2.0.4-0.20231020030327-4ecf7c282e37
+	github.com/tikv/pd/client v0.0.0-20230904040343-947701a32c05
 	github.com/timakin/bodyclose v0.0.0-20210704033933-f49887972144
 	github.com/twmb/murmur3 v1.1.3
 	github.com/uber/jaeger-client-go v2.22.1+incompatible
@@ -275,3 +275,5 @@ replace (
 	sourcegraph.com/sourcegraph/appdash => github.com/sourcegraph/appdash v0.0.0-20190731080439-ebfcffb1b5c0
 	sourcegraph.com/sourcegraph/appdash-data => github.com/sourcegraph/appdash-data v0.0.0-20151005221446-73f23eafcf67
 )
+
+replace github.com/tikv/client-go/v2 => github.com/zyguan/client-go/v2 v2.0.0-alpha.0.20240110111729-6e9a19b9e654

go.sum

@@ -940,8 +940,6 @@ github.com/tenntenn/text/transform v0.0.0-20200319021203-7eef512accb3 h1:f+jULpR
 github.com/tenntenn/text/transform v0.0.0-20200319021203-7eef512accb3/go.mod h1:ON8b8w4BN/kE1EOhwT0o+d62W65a6aPw1nouo9LMgyY=
 github.com/tiancaiamao/appdash v0.0.0-20181126055449-889f96f722a2 h1:mbAskLJ0oJfDRtkanvQPiooDH8HvJ2FBh+iKT/OmiQQ=
 github.com/tiancaiamao/appdash v0.0.0-20181126055449-889f96f722a2/go.mod h1:2PfKggNGDuadAa0LElHrByyrz4JPZ9fFx6Gs7nx7ZZU=
-github.com/tikv/client-go/v2 v2.0.4-0.20231020030327-4ecf7c282e37 h1:x4x8yO7tHtxOepMGpPnnLMVw2geDsrYbbbB7k+0zusY=
-github.com/tikv/client-go/v2 v2.0.4-0.20231020030327-4ecf7c282e37/go.mod h1:mmVCLP2OqWvQJPOIevQPZvGphzh/oq9vv8J5LDfpadQ=
 github.com/tikv/pd/client v0.0.0-20230904040343-947701a32c05 h1:e4hLUKfgfPeJPZwOfU+/I/03G0sn6IZqVcbX/5o+hvM=
 github.com/tikv/pd/client v0.0.0-20230904040343-947701a32c05/go.mod h1:MLIl+d2WbOF4A3U88WKtyXrQQW417wZDDvBcq2IW9bQ=
 github.com/timakin/bodyclose v0.0.0-20210704033933-f49887972144 h1:kl4KhGNsJIbDHS9/4U9yQo1UcPQM0kOMJHn29EoH/Ro=
@@ -999,6 +997,8 @@ github.com/yuin/goldmark v1.4.1/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 github.com/yusufpapurcu/wmi v1.2.2 h1:KBNDSne4vP5mbSWnJbO+51IMOXJB67QiYCSBrubbPRg=
 github.com/yusufpapurcu/wmi v1.2.2/go.mod h1:SBZ9tNy3G9/m5Oi98Zks0QjeHVDvuK0qfxQmPyzfmi0=
+github.com/zyguan/client-go/v2 v2.0.0-alpha.0.20240110111729-6e9a19b9e654 h1:Fyu8ZooUlfrRXUJP3hYpcm6wVjZoZ3vW6D8KU1hLnVk=
+github.com/zyguan/client-go/v2 v2.0.0-alpha.0.20240110111729-6e9a19b9e654/go.mod h1:mmVCLP2OqWvQJPOIevQPZvGphzh/oq9vv8J5LDfpadQ=
 go.etcd.io/bbolt v1.3.2/go.mod h1:IbVyRI1SCnLcuJnV2u8VeU0CEYM7e686BmAb1XKL+uU=
 go.etcd.io/bbolt v1.3.6 h1:/ecaJf0sk1l4l6V4awd65v2C3ILy7MSj+s/x1ADCIMU=
 go.etcd.io/bbolt v1.3.6/go.mod h1:qXsaaIqmgQH0T+OPdb99Bf+PKfBBQVAdyD6TY9G8XM4=

sessionctx/variable/sysvar.go

@@ -47,6 +47,7 @@ import (
 	"github.com/pingcap/tidb/util/versioninfo"
 	tikvcfg "github.com/tikv/client-go/v2/config"
 	tikvstore "github.com/tikv/client-go/v2/kv"
+	"github.com/tikv/client-go/v2/tikv"
 	atomic2 "go.uber.org/atomic"
 )
 
@@ -489,6 +490,24 @@ var defaultSysVars = []*SysVar{
 	}, GetGlobal: func(_ context.Context, s *SessionVars) (string, error) {
 		return BoolToOnOff(EnableRCReadCheckTS.Load()), nil
 	}},
+	{Scope: ScopeInstance, Name: TiKVClientReplicaSelectorExperimentalOptions, Value: "", Type: TypeStr, SetGlobal: func(_ context.Context, s *SessionVars, val string) error {
+		var opts tikv.ReplicaSelectorExperimentalOptions
+		if len(val) > 0 {
+			err := json.Unmarshal([]byte(val), &opts)
+			if err != nil {
+				return errors.Errorf("invalid json value %q: %v", val, err)
+			}
+			tikv.SetReplicaSelectorExperimentalOptions(opts)
+		}
+		return nil
+	}, GetGlobal: func(ctx context.Context, sv *SessionVars) (string, error) {
+		opts := tikv.GetReplicaSelectorExperimentalOptions()
+		raw, err := json.Marshal(opts)
+		if err != nil {
+			return "", errors.Trace(err)
+		}
+		return string(raw), nil
+	}},
 
 	/* The system variables below have GLOBAL scope  */
 	{Scope: ScopeGlobal, Name: MaxPreparedStmtCount, Value: strconv.FormatInt(DefMaxPreparedStmtCount, 10), Type: TypeInt, MinValue: -1, MaxValue: 1048576,
@@ -2608,6 +2627,8 @@ const (
 	MaxExecutionTime = "max_execution_time"
 	// TiKVClientReadTimeout is the name of the 'tikv_client_read_timeout' system variable.
 	TiKVClientReadTimeout = "tikv_client_read_timeout"
+	// TiKVClientReplicaSelectorExperimentalOptions is the name of the 'tikv_client_replica_selector_experimental_options' system variable.
+	TiKVClientReplicaSelectorExperimentalOptions = "tikv_client_replica_selector_experimental_options"
 	// ReadOnly is the name of the 'read_only' system variable.
 	ReadOnly = "read_only"
 	// DefaultAuthPlugin is the name of 'default_authentication_plugin' system variable.