add UnwarpCheckPointExecutor (#2298)

pkg/cluster/api/tidbapi.go

@@ -75,4 +75,3 @@ func (c *TiDBClient) FinishUpgrade() error {
 
 	return err
 }
-

pkg/cluster/executor/executor.go

@@ -118,6 +118,19 @@ func New(etype SSHType, sudo bool, c SSHConfig) (ctxt.Executor, error) {
 	return &CheckPointExecutor{executor, &c}, nil
 }
 
+// UnwarpCheckPointExecutor unwarp the CheckPointExecutor and return the real executor
+//
+// Sometimes we just want to get the output of a command, and the CheckPointExecutor will
+// always cache the output, it will be a problem when we want to get the real output.
+func UnwarpCheckPointExecutor(e ctxt.Executor) ctxt.Executor {
+	switch e := e.(type) {
+	case *CheckPointExecutor:
+		return e.Executor
+	default:
+		return e
+	}
+}
+
 func checkLocalIP(ip string) error {
 	ifaces, err := net.Interfaces()
 	if err != nil {

pkg/cluster/module/wait_for.go

@@ -21,6 +21,7 @@ import (
 
 	"github.com/pingcap/errors"
 	"github.com/pingcap/tiup/pkg/cluster/ctxt"
+	"github.com/pingcap/tiup/pkg/cluster/executor"
 	"github.com/pingcap/tiup/pkg/utils"
 	"go.uber.org/zap"
 )
@@ -71,7 +72,7 @@ func (w *WaitFor) Execute(ctx context.Context, e ctxt.Executor) (err error) {
 	}
 	if err := utils.Retry(func() error {
 		// only listing TCP ports
-		stdout, _, err := e.Execute(ctx, "ss -ltn", false)
+		stdout, _, err := executor.UnwarpCheckPointExecutor(e).Execute(ctx, "ss -ltn", false)
 		if err == nil {
 			switch w.c.State {
 			case "started":