Merge pull request #29470 from cyli/ask-for-unlock-key-only-if-locked

Check if a swarm is locked before asking a user to enter their unlock key

command/swarm/unlock.go

@@ -2,6 +2,7 @@ package swarm
 
 import (
 	"bufio"
+	"errors"
 	"fmt"
 	"io"
 	"strings"
@@ -24,6 +25,22 @@ func newUnlockCommand(dockerCli *command.DockerCli) *cobra.Command {
 			client := dockerCli.Client()
 			ctx := context.Background()
 
+			// First see if the node is actually part of a swarm, and if it's is actually locked first.
+			// If it's in any other state than locked, don't ask for the key.
+			info, err := client.Info(ctx)
+			if err != nil {
+				return err
+			}
+
+			switch info.Swarm.LocalNodeState {
+			case swarm.LocalNodeStateInactive:
+				return errors.New("Error: This node is not part of a swarm")
+			case swarm.LocalNodeStateLocked:
+				break
+			default:
+				return errors.New("Error: swarm is not locked")
+			}
+
 			key, err := readKey(dockerCli.In(), "Please enter unlock key: ")
 			if err != nil {
 				return err