return ServerError when failed to get cancelation confirmation

Author: Eygin Semen Leonidovich

mssql.go

@@ -23,9 +23,9 @@ import (
 
 // ReturnStatus may be used to return the return value from a proc.
 //
-//   var rs mssql.ReturnStatus
-//   _, err := db.Exec("theproc", &rs)
-//   log.Printf("return status = %d", rs)
+//	var rs mssql.ReturnStatus
+//	_, err := db.Exec("theproc", &rs)
+//	log.Printf("return status = %d", rs)
 type ReturnStatus int32
 
 var driverInstance = &Driver{processQueryText: true}
@@ -243,8 +243,6 @@ func (c *Conn) checkBadConn(ctx context.Context, err error, mayRetry bool) error
 		return nil
 	case io.EOF:
 		c.connectionGood = false
-	case ErrorCancelConfirmation:
-		c.connectionGood = false
 	case driver.ErrBadConn:
 		// It is an internal programming error if driver.ErrBadConn
 		// is ever passed to this function. driver.ErrBadConn should
@@ -879,22 +877,24 @@ func (r *Rows) ColumnTypeDatabaseTypeName(index int) string {
 // not a variable length type ok should return false.
 // If length is not limited other than system limits, it should return math.MaxInt64.
 // The following are examples of returned values for various types:
-//   TEXT          (math.MaxInt64, true)
-//   varchar(10)   (10, true)
-//   nvarchar(10)  (10, true)
-//   decimal       (0, false)
-//   int           (0, false)
-//   bytea(30)     (30, true)
+//
+//	TEXT          (math.MaxInt64, true)
+//	varchar(10)   (10, true)
+//	nvarchar(10)  (10, true)
+//	decimal       (0, false)
+//	int           (0, false)
+//	bytea(30)     (30, true)
 func (r *Rows) ColumnTypeLength(index int) (int64, bool) {
 	return makeGoLangTypeLength(r.cols[index].ti)
 }
 
 // It should return
 // the precision and scale for decimal types. If not applicable, ok should be false.
 // The following are examples of returned values for various types:
-//   decimal(38, 4)    (38, 4, true)
-//   int               (0, 0, false)
-//   decimal           (math.MaxInt64, math.MaxInt64, true)
+//
+//	decimal(38, 4)    (38, 4, true)
+//	int               (0, 0, false)
+//	decimal           (math.MaxInt64, math.MaxInt64, true)
 func (r *Rows) ColumnTypePrecisionScale(index int) (int64, int64, bool) {
 	return makeGoLangTypePrecisionScale(r.cols[index].ti)
 }
@@ -1321,22 +1321,24 @@ func (r *Rowsq) ColumnTypeDatabaseTypeName(index int) string {
 // not a variable length type ok should return false.
 // If length is not limited other than system limits, it should return math.MaxInt64.
 // The following are examples of returned values for various types:
-//   TEXT          (math.MaxInt64, true)
-//   varchar(10)   (10, true)
-//   nvarchar(10)  (10, true)
-//   decimal       (0, false)
-//   int           (0, false)
-//   bytea(30)     (30, true)
+//
+//	TEXT          (math.MaxInt64, true)
+//	varchar(10)   (10, true)
+//	nvarchar(10)  (10, true)
+//	decimal       (0, false)
+//	int           (0, false)
+//	bytea(30)     (30, true)
 func (r *Rowsq) ColumnTypeLength(index int) (int64, bool) {
 	return makeGoLangTypeLength(r.cols[index].ti)
 }
 
 // It should return
 // the precision and scale for decimal types. If not applicable, ok should be false.
 // The following are examples of returned values for various types:
-//   decimal(38, 4)    (38, 4, true)
-//   int               (0, 0, false)
-//   decimal           (math.MaxInt64, math.MaxInt64, true)
+//
+//	decimal(38, 4)    (38, 4, true)
+//	int               (0, 0, false)
+//	decimal           (math.MaxInt64, math.MaxInt64, true)
 func (r *Rowsq) ColumnTypePrecisionScale(index int) (int64, int64, bool) {
 	return makeGoLangTypePrecisionScale(r.cols[index].ti)
 }

mssql_test.go

@@ -127,10 +127,6 @@ func TestCheckBadConn(t *testing.T) {
 		{io.EOF, true, false, newRetryableError(io.EOF), false},
 		{io.EOF, false, true, io.EOF, false},
 		{io.EOF, true, true, io.EOF, false},
-		{ErrorCancelConfirmation, false, false, ErrorCancelConfirmation, false},
-		{ErrorCancelConfirmation, true, false, newRetryableError(ErrorCancelConfirmation), false},
-		{ErrorCancelConfirmation, false, true, ErrorCancelConfirmation, false},
-		{ErrorCancelConfirmation, true, true, ErrorCancelConfirmation, false},
 		{netErr, false, false, netErr, false},
 		{netErr, true, false, newRetryableError(netErr), false},
 		{netErr, false, true, netErr, false},

queries_test.go

@@ -1419,8 +1419,8 @@ func TestProcessQueryCancelConfirmationError(t *testing.T) {
 		t.Error("processQueryResponse expected to fail but it succeeded")
 	}
 	// should not fail with ErrBadConn because query was successfully sent to server
-	if err != ErrorCancelConfirmation {
-		t.Error("processQueryResponse expected to fail with ErrorCancelConfirmation error but failed with other error: ", err)
+	if !errors.As(err, &ServerError{}) {
+		t.Error("processQueryResponse expected to fail with ServerError error but failed with other error: ", err)
 	}
 
 	if conn.connectionGood {

token.go

@@ -3,7 +3,6 @@ package mssql
 import (
 	"context"
 	"encoding/binary"
-	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -99,8 +98,6 @@ const (
 	// TODO implement more flags
 )
 
-var ErrorCancelConfirmation = errors.New("did not get cancellation confirmation from the server")
-
 // interface for all tokens
 type tokenStruct interface{}
 
@@ -961,7 +958,7 @@ func (t tokenProcessor) nextToken() (tokenStruct, error) {
 		}
 		// we did not get cancellation confirmation, something is not
 		// right, this connection is not usable anymore
-		return nil, ErrorCancelConfirmation
+		return nil, ServerError{Error{Message: "did not get cancellation confirmation from the server"}}
 	}
 }