From 4b6053134df46045ae8aa00a7f5f95857b517d9d Mon Sep 17 00:00:00 2001
From: Ti Chi Robot <ti-community-prow-bot@tidb.io>
Date: Wed, 8 Mar 2023 11:07:12 +0800
Subject: [PATCH] cmd(ticdc): print error msg if an invalid input was read
 (#7936) (#8442)

close pingcap/tiflow#7903
---
 pkg/cmd/cli/cli_changefeed_helper.go | 29 ++++++++++++++++------------
 pkg/cmd/cli/cli_changefeed_update.go |  9 ++-------
 pkg/cmd/cli/cli_unsafe.go            | 13 ++-----------
 3 files changed, 21 insertions(+), 30 deletions(-)

diff --git a/pkg/cmd/cli/cli_changefeed_helper.go b/pkg/cmd/cli/cli_changefeed_helper.go
index 530f73c141b..68e9a2168b0 100644
--- a/pkg/cmd/cli/cli_changefeed_helper.go
+++ b/pkg/cmd/cli/cli_changefeed_helper.go
@@ -39,6 +39,19 @@ const (
 	tsGapWarning = 86400 * 1000
 )
 
+func readInput(cmd *cobra.Command) bool {
+	var yOrN string
+	_, err := fmt.Scan(&yOrN)
+	if err != nil {
+		cmd.Printf("Received invalid input: %s, abort the command.\n", err.Error())
+		return false
+	}
+	if strings.ToLower(strings.TrimSpace(yOrN)) != "y" {
+		return false
+	}
+	return true
+}
+
 // confirmLargeDataGap checks if a large data gap is used.
 func confirmLargeDataGap(cmd *cobra.Command, currentPhysical int64, startTs uint64) error {
 	tsGap := currentPhysical - oracle.ExtractPhysical(startTs)
@@ -48,12 +61,8 @@ func confirmLargeDataGap(cmd *cobra.Command, currentPhysical int64, startTs uint
 			"large data may cause OOM, confirm to continue at your own risk [Y/N]\n",
 			time.Duration(tsGap)*time.Millisecond,
 		)
-		var yOrN string
-		_, err := fmt.Scan(&yOrN)
-		if err != nil {
-			return err
-		}
-		if strings.ToLower(strings.TrimSpace(yOrN)) != "y" {
+		confirmed := readInput(cmd)
+		if !confirmed {
 			return errors.NewNoStackError("abort changefeed create or resume")
 		}
 	}
@@ -64,12 +73,8 @@ func confirmLargeDataGap(cmd *cobra.Command, currentPhysical int64, startTs uint
 // confirmIgnoreIneligibleTables confirm if user need to ignore ineligible tables.
 func confirmIgnoreIneligibleTables(cmd *cobra.Command) error {
 	cmd.Printf("Could you agree to ignore those tables, and continue to replicate [Y/N]\n")
-	var yOrN string
-	_, err := fmt.Scan(&yOrN)
-	if err != nil {
-		return err
-	}
-	if strings.ToLower(strings.TrimSpace(yOrN)) != "y" {
+	confirmed := readInput(cmd)
+	if !confirmed {
 		cmd.Printf("No changefeed is created because you don't want to ignore some tables.\n")
 		return errors.NewNoStackError("abort changefeed create or resume")
 	}
diff --git a/pkg/cmd/cli/cli_changefeed_update.go b/pkg/cmd/cli/cli_changefeed_update.go
index 77152fb449b..348524dd864 100644
--- a/pkg/cmd/cli/cli_changefeed_update.go
+++ b/pkg/cmd/cli/cli_changefeed_update.go
@@ -14,7 +14,6 @@
 package cli
 
 import (
-	"fmt"
 	"strings"
 
 	"github.com/pingcap/errors"
@@ -117,12 +116,8 @@ func (o *updateChangefeedOptions) run(cmd *cobra.Command) error {
 
 	if !o.commonChangefeedOptions.noConfirm {
 		cmd.Printf("Could you agree to apply changes above to changefeed [Y/N]\n")
-		var yOrN string
-		_, err = fmt.Scan(&yOrN)
-		if err != nil {
-			return err
-		}
-		if strings.ToLower(strings.TrimSpace(yOrN)) != "y" {
+		confirmed := readInput(cmd)
+		if !confirmed {
 			cmd.Printf("No update to changefeed.\n")
 			return nil
 		}
diff --git a/pkg/cmd/cli/cli_unsafe.go b/pkg/cmd/cli/cli_unsafe.go
index 4c0fe3e47a6..d9a60fcd905 100644
--- a/pkg/cmd/cli/cli_unsafe.go
+++ b/pkg/cmd/cli/cli_unsafe.go
@@ -14,9 +14,6 @@
 package cli
 
 import (
-	"fmt"
-	"strings"
-
 	"github.com/pingcap/errors"
 	"github.com/pingcap/tiflow/pkg/cmd/factory"
 	"github.com/spf13/cobra"
@@ -39,14 +36,8 @@ func (o *unsafeCommonOptions) confirmMetaDelete(cmd *cobra.Command) error {
 	}
 
 	cmd.Printf("Confirm that you know what this command will do and use it at your own risk [Y/N]\n")
-
-	var yOrN string
-	_, err := fmt.Scan(&yOrN)
-	if err != nil {
-		return err
-	}
-
-	if strings.ToLower(strings.TrimSpace(yOrN)) != "y" {
+	confirmed := readInput(cmd)
+	if !confirmed {
 		return errors.NewNoStackError("abort meta command")
 	}