Merge pull request #376 from ydb-platform/session-balancing

* Marked sessions which creates from `database/sql` driver as support…

Author: asmyasnikov

CHANGELOG.md

@@ -1,3 +1,5 @@
+* Marked sessions which creates from `database/sql` driver as supported server-side session balancing
+
 ## v3.37.7
 * Changed type of truncated result error from `StreamExecuteScanQuery` to retryable error
 * Added closing sessions if node removed from discovery results

internal/xerrors/operation.go

@@ -24,7 +24,7 @@ func (e *operationError) Code() int32 {
 }
 
 func (e *operationError) Name() string {
-	return e.code.String()
+	return "operation/" + e.code.String()
 }
 
 type operationStatus interface {

internal/xerrors/retryable.go

@@ -19,10 +19,7 @@ func (e *retryableError) Code() int32 {
 }
 
 func (e *retryableError) Name() string {
-	if e.name != "" {
-		return e.name
-	}
-	return "CUSTOM"
+	return "retryable/" + e.name
 }
 
 func (e *retryableError) OperationStatus() operation.Status {
@@ -67,7 +64,8 @@ func WithDeleteSession() RetryableErrorOption {
 
 func Retryable(err error, opts ...RetryableErrorOption) error {
 	re := &retryableError{
-		err: err,
+		err:  err,
+		name: "CUSTOM",
 	}
 	for _, o := range opts {
 		o(re)

internal/xerrors/transport.go

@@ -30,7 +30,7 @@ func (e *transportError) Code() int32 {
 }
 
 func (e *transportError) Name() string {
-	return e.code.String()
+	return "transport/" + e.code.String()
 }
 
 type teOpt func(te *transportError)

internal/xsql/connector.go

@@ -5,6 +5,7 @@ import (
 	"database/sql/driver"
 	"io"
 
+	"github.com/ydb-platform/ydb-go-sdk/v3/internal/meta"
 	"github.com/ydb-platform/ydb-go-sdk/v3/internal/xerrors"
 	"github.com/ydb-platform/ydb-go-sdk/v3/scripting"
 	"github.com/ydb-platform/ydb-go-sdk/v3/table"
@@ -115,7 +116,11 @@ func (c *Connector) Connect(ctx context.Context) (_ driver.Conn, err error) {
 	defer func() {
 		onDone(err)
 	}()
-	s, err := c.connection.Table().CreateSession(ctx)
+	s, err := c.connection.Table().CreateSession(
+		meta.WithAllowFeatures(ctx,
+			meta.HintSessionBalancer,
+		),
+	)
 	if err != nil {
 		return nil, xerrors.WithStackTrace(err)
 	}