Merge pull request #1367 from frodopwns/1302-require-confirm-on-delete

Require a confirmation when deleting resources #1302

cmd/kops/delete.go

@@ -17,17 +17,55 @@ limitations under the License.
 package main
 
 import (
+	"fmt"
+	"os"
+	"strings"
+
+	"k8s.io/kops/util/pkg/ui"
+
 	"github.com/spf13/cobra"
 )
 
+var confirmDelete bool
+
 // deleteCmd represents the delete command
 var deleteCmd = &cobra.Command{
 	Use:        "delete",
 	Short:      "delete clusters",
 	Long:       `Delete clusters`,
 	SuggestFor: []string{"rm"},
+	PersistentPreRun: func(cmd *cobra.Command, args []string) {
+		// cobra doesn't give you the full arg list even though it should.
+		args = os.Args
+
+		// args should be [delete, resource, resource name]
+		// if there are less args than 3 confirming isnt necessary as the child command will fail
+		if !confirmDelete && len(args) >= 3 {
+			message := fmt.Sprintf(
+				"Do you really want to %s? This action cannot be undone.",
+				strings.Join(args[1:], " "),
+			)
+
+			c := &ui.ConfirmArgs{
+				Out:     os.Stdout,
+				Message: message,
+				Default: "no",
+				Retries: 2,
+			}
+
+			confirmed, err := ui.GetConfirm(c)
+			if err != nil {
+				exitWithError(err)
+			}
+			if !confirmed {
+				os.Exit(1)
+			}
+
+		}
+	},
 }
 
 func init() {
+	deleteCmd.PersistentFlags().BoolVarP(&confirmDelete, "yes", "y", false, "Auto confirm deletetion.")
 	rootCommand.AddCommand(deleteCmd)
 }

cmd/kops/delete_cluster.go

@@ -18,6 +18,9 @@ package main
 
 import (
 	"fmt"
+	"os"
+	"strings"
+
 	"github.com/spf13/cobra"
 	api "k8s.io/kops/pkg/apis/kops"
 	"k8s.io/kops/pkg/apis/kops/registry"
@@ -28,7 +31,6 @@ import (
 	"k8s.io/kops/upup/pkg/kutil"
 	"k8s.io/kops/util/pkg/tables"
 	"k8s.io/kops/util/pkg/vfs"
-	"os"
 )
 
 type DeleteClusterCmd struct {
@@ -55,7 +57,15 @@ func init() {
 
 	deleteCmd.AddCommand(cmd)
 
-	cmd.Flags().BoolVar(&deleteCluster.Yes, "yes", false, "Delete without confirmation")
+	// had to do this because this init function is running before the flag is set
+	for _, arg := range os.Args {
+		arg = strings.ToLower(arg)
+		if arg == "-y" || arg == "--yes" {
+			deleteCluster.Yes = true
+			break
+		}
+	}
+
 	cmd.Flags().BoolVar(&deleteCluster.Unregister, "unregister", false, "Don't delete cloud resources, just unregister the cluster")
 	cmd.Flags().BoolVar(&deleteCluster.External, "external", false, "Delete an external cluster")
 

cmd/kops/delete_confirm_test.go

@@ -0,0 +1,86 @@
+/*
+Copyright 2016 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+
+	"k8s.io/kops/util/pkg/ui"
+)
+
+// TestContainsString tests the ContainsString() function
+func TestContainsString(t *testing.T) {
+	testString := "my test string"
+	answer := ui.ContainsString(strings.Split(testString, " "), "my")
+	if !answer {
+		t.Fatal("Failed to find string using ui.ContainsString()")
+	}
+	answer = ui.ContainsString(strings.Split(testString, " "), "string")
+	if !answer {
+		t.Fatal("Failed to find string using ui.ContainsString()")
+	}
+	answer = ui.ContainsString(strings.Split(testString, " "), "random")
+	if answer {
+		t.Fatal("Found string that does not exist using ui.ContainsString()")
+	}
+}
+
+// TestConfirmation attempts to test the majority of the ui.GetConfirm function used in the 'kogs delete' commands
+func TestConfirmation(t *testing.T) {
+	var out bytes.Buffer
+	c := &ui.ConfirmArgs{
+		Message: "Are you sure you want to remove?",
+		Out:     &out,
+		TestVal: "no",
+		Default: "no",
+	}
+
+	answer, err := ui.GetConfirm(c)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(out.String(), "Are you sure") {
+		t.Fatal("Confirmation not in output")
+	}
+	if !strings.Contains(out.String(), "y/N") {
+		t.Fatal("Default 'No' was not set")
+	}
+	if answer == true {
+		t.Fatal("Confirmation should have been denied.")
+	}
+
+	c.Default = "yes"
+	answer, err = ui.GetConfirm(c)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(out.String(), "Y/n") {
+		t.Fatal("Default 'Yes' was not set")
+	}
+
+	c.TestVal = "yes"
+	answer, err = ui.GetConfirm(c)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if answer != true {
+		t.Fatal("Confirmation should have been approved.")
+	}
+
+}

hack/.packages

@@ -62,4 +62,5 @@ k8s.io/kops/upup/tools/generators/fitask
 k8s.io/kops/upup/tools/generators/pkg/codegen
 k8s.io/kops/util/pkg/hashing
 k8s.io/kops/util/pkg/tables
+k8s.io/kops/util/pkg/ui
 k8s.io/kops/util/pkg/vfs

util/pkg/ui/user.go

@@ -0,0 +1,101 @@
+/*
+Copyright 2016 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package ui
+
+import (
+	"fmt"
+	"io"
+	"strings"
+)
+
+// ConfirmArgs encapsulates the arguments that can he passed to GetConfirm
+type ConfirmArgs struct {
+	Out        io.Writer // os.Stdout or &bytes.Buffer used to putput the message above the confirmation
+	Message    string    // what you want to say to the user before confirming
+	Default    string    // if you hit enter instead of yes or no shoudl it approve or deny
+	TestVal    string    // if you need to test without the interactive prompt then set the user response here
+	Retries    int       // how many tines to ask for a valid confirmation before giving up
+	RetryCount int       // how many attempts have been made
+}
+
+// GetConfirm prompts a user for a yes or no answer.
+// In order to test this function som extra parameters are reqired:
+//
+// out: an io.Writer that allows you to direct prints to stdout or another location
+// message: the string that will be printed just before prompting for a yes or no.
+// answer: "", "yes", or "no" - this allows for easier testing
+func GetConfirm(c *ConfirmArgs) (bool, error) {
+	if c.Default != "" {
+		c.Default = strings.ToLower(c.Default)
+	}
+	answerTemplate := "(%s/%s)"
+	switch c.Default {
+	case "yes", "y":
+		c.Message = c.Message + fmt.Sprintf(answerTemplate, "Y", "n")
+	case "no", "n":
+		c.Message = c.Message + fmt.Sprintf(answerTemplate, "y", "N")
+	default:
+		c.Message = c.Message + fmt.Sprintf(answerTemplate, "y", "n")
+	}
+	fmt.Fprintln(c.Out, c.Message)
+
+	// these are the acceptable answers
+	okayResponses := []string{"y", "yes"}
+	nokayResponses := []string{"n", "no"}
+	response := c.TestVal
+
+	// only prompt user if you predefined answer was passed in
+	if response == "" {
+		_, err := fmt.Scanln(&response)
+		if err != nil {
+			return false, err
+		}
+	}
+
+	responseLower := strings.ToLower(response)
+	// make sure the response is valid
+	if ContainsString(okayResponses, responseLower) {
+		return true, nil
+	} else if ContainsString(nokayResponses, responseLower) {
+		return false, nil
+	} else if c.Default != "" && response == "" {
+		if string(c.Default[0]) == "y" {
+			return true, nil
+		}
+		return false, nil
+	}
+
+	fmt.Printf("invalid response: %s\n\n", response)
+
+	// if c.RetryCount exceeds the requested number of retries then give up
+	if c.RetryCount >= c.Retries {
+		return false, nil
+	}
+
+	c.RetryCount++
+	return GetConfirm(c)
+}
+
+// ContainsString returns true if slice contains the element
+func ContainsString(slice []string, element string) bool {
+	for _, arg := range slice {
+		if arg == element {
+			return true
+		}
+	}
+	return false
+}