Add --force to node removal

Signed-off-by: Diogo Monica <diogo.monica@gmail.com>
(cherry picked from commit a327c231b5)
Signed-off-by: Tibor Vass <tibor@docker.com>

api/client/node/remove.go

@@ -7,26 +7,36 @@ import (
 
 	"github.com/docker/docker/api/client"
 	"github.com/docker/docker/cli"
+	"github.com/docker/engine-api/types"
 	"github.com/spf13/cobra"
 )
 
+type removeOptions struct {
+	force bool
+}
+
 func newRemoveCommand(dockerCli *client.DockerCli) *cobra.Command {
-	return &cobra.Command{
-		Use:     "rm NODE [NODE...]",
+	opts := removeOptions{}
+
+	cmd := &cobra.Command{
+		Use:     "rm [OPTIONS] NODE [NODE...]",
 		Aliases: []string{"remove"},
 		Short:   "Remove one or more nodes from the swarm",
 		Args:    cli.RequiresMinArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
-			return runRemove(dockerCli, args)
+			return runRemove(dockerCli, args, opts)
 		},
 	}
+	flags := cmd.Flags()
+	flags.BoolVar(&opts.force, "force", false, "Force remove an active node")
+	return cmd
 }
 
-func runRemove(dockerCli *client.DockerCli, args []string) error {
+func runRemove(dockerCli *client.DockerCli, args []string, opts removeOptions) error {
 	client := dockerCli.Client()
 	ctx := context.Background()
 	for _, nodeID := range args {
-		err := client.NodeRemove(ctx, nodeID)
+		err := client.NodeRemove(ctx, nodeID, types.NodeRemoveOptions{Force: opts.force})
 		if err != nil {
 			return err
 		}