fix: render table_not_found error correctly (#372)

pkg/mysql/conn.go

@@ -25,12 +25,15 @@ import (
  "fmt"
  "io"
  "net"
+ "regexp"
  "strings"
  "sync"
  "time"
 )
 
 import (
+ pmysql "github.com/arana-db/parser/mysql"
+
  gxnet "github.com/dubbogo/gost/net"
 
  "github.com/pkg/errors"
@@ -692,11 +695,33 @@ func (c *Conn) writeOKPacketWithEOFHeader(affectedRows, lastInsertID uint64, fla
  return c.writeEphemeralPacket()
 }
 
+func (c *Conn) fixErrNoSuchTable(errorMessage string) string {
+ // FIXME: workaround, need refinement in the future.
+ // Table 'employees_0000.teacher' doesn't exist
+ if matches := getFixErrNoSuchTableRegexp().FindStringSubmatch(errorMessage); len(matches) == 3 {
+ var sb strings.Builder
+ sb.Grow(len(errorMessage))
+ sb.WriteString("Table '")
+ sb.WriteString(c.Schema)
+ sb.WriteByte('.')
+ sb.WriteString(matches[2])
+ sb.WriteString("' doesn't exist")
+ return sb.String()
+ }
+
+ return errorMessage
+}
+
 // writeErrorPacket writes an error packet.
 // Server -> Client.
 // This method returns a generic error, not a SQLError.
 func (c *Conn) writeErrorPacket(errorCode uint16, sqlState string, format string, args ...interface{}) error {
  errorMessage := fmt.Sprintf(format, args...)
+ switch errorCode {
+ case pmysql.ErrNoSuchTable:
+ errorMessage = c.fixErrNoSuchTable(errorMessage)
+ }
+
  length := 1 + 2 + 1 + 5 + len(errorMessage)
  data := c.startEphemeralPacket(length)
  pos := 0
@@ -865,3 +890,15 @@ func (c *Conn) GetTLSClientCerts() []*x509.Certificate {
 func (c *Conn) GetNetConn() net.Conn {
  return c.conn
 }
+
+var (
+ _fixErrNoSuchTableRegexp *regexp.Regexp
+ _fixErrNoSuchTableRegexpOnce sync.Once
+)
+
+func getFixErrNoSuchTableRegexp() *regexp.Regexp {
+ _fixErrNoSuchTableRegexpOnce.Do(func() {
+ _fixErrNoSuchTableRegexp = regexp.MustCompile(`^Table '([^.']+)\.([^.']+)' doesn't exist$`)
+ })
+ return _fixErrNoSuchTableRegexp
+}