From 7e0fb1585da92dc99109417937d8b9917b425ad6 Mon Sep 17 00:00:00 2001
From: Ying Li <ying.li@docker.com>
Date: Thu, 15 Dec 2016 18:36:37 -0800
Subject: [PATCH] Before asking a user for the unlock key when they run `docker
 swarm unlock`, actually check to see if the node is part of a swarm, and if
 so, if it is unlocked first. If neither of these are true, abort the command.

Signed-off-by: Ying Li <ying.li@docker.com>
Upstream-commit: e4102ce61e8727296c0acc75531088064173de8c
Component: cli
---
 components/cli/command/swarm/unlock.go | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/components/cli/command/swarm/unlock.go b/components/cli/command/swarm/unlock.go
index 048fb56e3d..abb9e89fe7 100644
--- a/components/cli/command/swarm/unlock.go
+++ b/components/cli/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