sync upstream

ref:f6ada2eb4b2d355828184bf7741739cd9af2c994

dialer.go

@@ -66,9 +66,10 @@ func (d *Dialer) Dial(ctx context.Context, addr string) (Driver, error) {
 		timeout:   d.Timeout,
 		config:    config,
 		meta: &meta{
-			trace:       config.Trace,
-			database:    config.Database,
-			credentials: config.Credentials,
+			trace:        config.Trace,
+			database:     config.Database,
+			credentials:  config.Credentials,
+			requestsType: config.RequestsType,
 		},
 	}).dial(ctx, addr)
 }

driver.go

@@ -149,6 +149,10 @@ type DriverConfig struct {
 	// is, currently this option may be called as experimental.
 	// You have been warned.
 	PreferLocalEndpoints bool
+
+	// RequestsType set an additional type hint to all requests.
+	// It is needed only for debug purposes and advanced cases.
+	RequestsType string
 }
 
 func (d *DriverConfig) withDefaults() (c DriverConfig) {

meta.go

@@ -8,15 +8,18 @@ import (
 )
 
 const (
-	metaDatabase = "x-ydb-database"
-	metaTicket   = "x-ydb-auth-ticket"
-	metaVersion  = "x-ydb-sdk-build-info"
+	metaDatabase    = "x-ydb-database"
+	metaTicket      = "x-ydb-auth-ticket"
+	metaVersion     = "x-ydb-sdk-build-info"
+	metaRequestType = "x-ydb-request-type"
+	metaTeraceID    = "x-ydb-trace-id"
 )
 
 type meta struct {
-	trace       DriverTrace
-	credentials Credentials
-	database    string
+	trace        DriverTrace
+	credentials  Credentials
+	database     string
+	requestsType string
 
 	once  sync.Once
 	mu    sync.RWMutex
@@ -25,10 +28,17 @@ type meta struct {
 }
 
 func (m *meta) make() metadata.MD {
-	return metadata.New(map[string]string{
+	newMeta := metadata.New(map[string]string{
 		metaDatabase: m.database,
 		metaVersion:  Version,
 	})
+	if m.requestsType != "" {
+		newMeta.Set(metaRequestType, m.requestsType)
+	}
+	if m.token != "" {
+		newMeta.Set(metaTicket, m.token)
+	}
+	return newMeta
 }
 
 func (m *meta) md(ctx context.Context) (md metadata.MD, _ error) {
@@ -52,6 +62,9 @@ func (m *meta) md(ctx context.Context) (md metadata.MD, _ error) {
 		// Continue.
 
 	case ErrCredentialsDropToken:
+		m.mu.Lock()
+		defer m.mu.Unlock()
+		m.token = ""
 		return m.make(), nil
 
 	case ErrCredentialsKeepToken:
@@ -77,10 +90,6 @@ func (m *meta) md(ctx context.Context) (md metadata.MD, _ error) {
 	}
 	m.token = token
 
-	m.curr = make(metadata.MD, 3)
-	m.curr.Set(metaDatabase, m.database)
-	m.curr.Set(metaTicket, m.token)
-	m.curr.Set(metaVersion, Version)
-
+	m.curr = m.make()
 	return m.curr, nil
 }

meta_test.go

@@ -10,7 +10,8 @@ import (
 func TestMetaErrDropToken(t *testing.T) {
 	var call int
 	m := &meta{
-		database: "database",
+		database:     "database",
+		requestsType: "requestType",
 		credentials: CredentialsFunc(func(context.Context) (string, error) {
 			if call == 0 {
 				call++
@@ -26,19 +27,22 @@ func TestMetaErrDropToken(t *testing.T) {
 	}
 	assertMetaHasDatabase(t, md1)
 	assertMetaHasToken(t, md1)
+	assertMetaHasRequestType(t, md1)
 
 	md2, err := m.md(context.Background())
 	if err != nil {
 		t.Fatal(err)
 	}
 	assertMetaHasDatabase(t, md2)
 	assertMetaHasNoToken(t, md2)
+	assertMetaHasRequestType(t, md2)
 }
 
 func TestMetaErrKeepToken(t *testing.T) {
 	var call int
 	m := &meta{
-		database: "database",
+		database:     "database",
+		requestsType: "requestType",
 		credentials: CredentialsFunc(func(context.Context) (string, error) {
 			if call == 0 {
 				call++
@@ -54,13 +58,15 @@ func TestMetaErrKeepToken(t *testing.T) {
 	}
 	assertMetaHasDatabase(t, md1)
 	assertMetaHasToken(t, md1)
+	assertMetaHasRequestType(t, md1)
 
 	md2, err := m.md(context.Background())
 	if err != nil {
 		t.Fatal(err)
 	}
 	assertMetaHasDatabase(t, md2)
-	assertMetaHasToken(t, md1)
+	assertMetaHasToken(t, md2)
+	assertMetaHasRequestType(t, md2)
 }
 
 func assertMetaHasDatabase(t *testing.T, md metadata.MD) {
@@ -78,3 +84,8 @@ func assertMetaHasNoToken(t *testing.T, md metadata.MD) {
 		t.Errorf("unexpected token info in meta")
 	}
 }
+func assertMetaHasRequestType(t *testing.T, md metadata.MD) {
+	if len(md.Get(metaRequestType)) == 0 {
+		t.Errorf("no request type info in meta")
+	}
+}