Merge pull request #9 from jjeffcaii/feat/show_topology

feat: support SHOW_TOPOLOGY

ast/dml.go

@@ -16,11 +16,12 @@ package ast
 import (
 	"strings"
 
+	"github.com/pingcap/errors"
+
 	"github.com/arana-db/parser/auth"
 	"github.com/arana-db/parser/format"
 	"github.com/arana-db/parser/model"
 	"github.com/arana-db/parser/mysql"
-	"github.com/pingcap/errors"
 )
 
 var (
@@ -2605,6 +2606,7 @@ const (
 	ShowPlacementForTable
 	ShowPlacementForPartition
 	ShowPlacementLabels
+	ShowTopology
 )
 
 const (
@@ -2691,6 +2693,11 @@ func (n *ShowStmt) Restore(ctx *format.RestoreCtx) error {
 		if err := n.Table.Restore(ctx); err != nil {
 			return errors.Annotate(err, "An error occurred while restore ShowStmt.Table")
 		}
+	case ShowTopology:
+		ctx.WriteKeyWord("TOPOLOGY FROM ")
+		if err := n.Table.Restore(ctx); err != nil {
+			return errors.Annotate(err, "An error occurred while restore ShowStmt.Table")
+		}
 	case ShowCreateView:
 		ctx.WriteKeyWord("CREATE VIEW ")
 		if err := n.Table.Restore(ctx); err != nil {

misc.go

@@ -622,6 +622,7 @@ var tokenMap = map[string]int{
 	"SEND_CREDENTIALS_TO_TIKV": sendCredentialsToTiKV,
 	"SEPARATOR":                separator,
 	"SEQUENCE":                 sequence,
+	"TOPOLOGY":                 topology,
 	"SERIAL":                   serial,
 	"SERIALIZABLE":             serializable,
 	"SESSION":                  session,