parser: support do some adminStmt in read-only mode (#37635)

close pingcap/tidb#37631

executor/executor_test.go

@@ -4308,6 +4308,7 @@ func TestAdminShowDDLJobs(t *testing.T) {
 	require.NoError(t, err)
 	err = meta.NewMeta(txn).AddHistoryDDLJob(job, true)
 	require.NoError(t, err)
+	tk.Session().StmtCommit()
 
 	re = tk.MustQuery("admin show ddl jobs 1")
 	row = re.Rows()[0]

parser/ast/util.go

@@ -55,6 +55,15 @@ func IsReadOnly(node Node) bool {
 			}
 		}
 		return true
+	case *AdminStmt:
+		switch node.(*AdminStmt).Tp {
+		case AdminShowTelemetry, AdminShowDDL, AdminShowDDLJobs, AdminShowSlow,
+			AdminCaptureBindings, AdminShowNextRowID, AdminShowDDLJobQueries,
+			AdminShowDDLJobQueriesWithRange:
+			return true
+		default:
+			return false
+		}
 	default:
 		return false
 	}

tests/readonlytest/readonly_test.go

@@ -155,6 +155,12 @@ func TestRestriction(t *testing.T) {
 	require.Error(t, err)
 	require.Equal(t, err.Error(), PriviledgedErrMsg)
 
+	// can do some Admin stmts
+	_, err = s.udb.Exec("admin show ddl jobs")
+	require.NoError(t, err)
+	_, err = s.udb.Exec("admin show slow recent 1")
+	require.NoError(t, err)
+
 	// turn off tidb_restricted_read_only does not affect tidb_super_read_only
 	setVariableNoError(t, s.db, TiDBRestrictedReadOnly, 0)