func runJoin(dockerCli *client.DockerCli, opts joinOptions) error {
	client := dockerCli.Client()
	ctx := context.Background()

	req := swarm.JoinRequest{
		JoinToken:   opts.token,
		ListenAddr:  opts.listenAddr.String(),
		RemoteAddrs: []string{opts.remote},
	}
	err := client.SwarmJoin(ctx, req)
	if err != nil {
		return err
	}

	info, err := client.Info(ctx)
	if err != nil {
		return err
	}

	_, _, err = client.NodeInspectWithRaw(ctx, info.Swarm.NodeID)
	if err != nil {
		// TODO(aaronl): is there a better way to do this?
		if strings.Contains(err.Error(), "This node is not a swarm manager.") {
			fmt.Fprintln(dockerCli.Out(), "This node joined a swarm as a worker.")
		}
	} else {
		fmt.Fprintln(dockerCli.Out(), "This node joined a swarm as a manager.")
	}

	return nil
}

func runTasks(dockerCli *client.DockerCli, opts tasksOptions) error {
	client := dockerCli.Client()
	ctx := context.Background()

	nodeRef, err := nodeReference(client, ctx, opts.nodeID)
	if err != nil {
		return nil
	}
	node, _, err := client.NodeInspectWithRaw(ctx, nodeRef)
	if err != nil {
		return err
	}

	filter := opts.filter.Value()
	filter.Add("node", node.ID)
	if !opts.all && !filter.Include("desired-state") {
		filter.Add("desired-state", string(swarm.TaskStateRunning))
		filter.Add("desired-state", string(swarm.TaskStateAccepted))
	}

	tasks, err := client.TaskList(
		ctx,
		types.TaskListOptions{Filter: filter})
	if err != nil {
		return err
	}

	return task.Print(dockerCli, ctx, tasks, idresolver.New(client, opts.noResolve))
}

func updateNodes(dockerCli *client.DockerCli, nodes []string, mergeNode func(node *swarm.Node) error, success func(nodeID string)) error {
	client := dockerCli.Client()
	ctx := context.Background()

	for _, nodeID := range nodes {
		node, _, err := client.NodeInspectWithRaw(ctx, nodeID)
		if err != nil {
			return err
		}

		err = mergeNode(&node)
		if err != nil {
			if err == errNoRoleChange {
				continue
			}
			return err
		}
		err = client.NodeUpdate(ctx, node.ID, node.Version, node.Spec)
		if err != nil {
			return err
		}
		success(nodeID)
	}
	return nil
}

func printJoinCommand(ctx context.Context, dockerCli *client.DockerCli, nodeID string, worker bool, manager bool) error {
	client := dockerCli.Client()

	swarm, err := client.SwarmInspect(ctx)
	if err != nil {
		return err
	}

	node, _, err := client.NodeInspectWithRaw(ctx, nodeID)
	if err != nil {
		return err
	}

	if node.ManagerStatus != nil {
		if worker {
			fmt.Fprintf(dockerCli.Out(), "To add a worker to this swarm, run the following command:\n    docker swarm join \\\n    --token %s \\\n    %s\n", swarm.JoinTokens.Worker, node.ManagerStatus.Addr)
		}
		if manager {
			if worker {
				fmt.Fprintln(dockerCli.Out())
			}
			fmt.Fprintf(dockerCli.Out(), "To add a manager to this swarm, run the following command:\n    docker swarm join \\\n    --token %s \\\n    %s\n", swarm.JoinTokens.Manager, node.ManagerStatus.Addr)
		}
	}

	return nil
}

func runInspect(dockerCli *client.DockerCli, opts inspectOptions) error {
	client := dockerCli.Client()
	ctx := context.Background()
	getRef := func(ref string) (interface{}, []byte, error) {
		nodeRef, err := Reference(client, ctx, ref)
		if err != nil {
			return nil, nil, err
		}
		node, _, err := client.NodeInspectWithRaw(ctx, nodeRef)
		return node, nil, err
	}

	if !opts.pretty {
		return inspect.Inspect(dockerCli.Out(), opts.nodeIds, opts.format, getRef)
	}
	return printHumanFriendly(dockerCli.Out(), opts.nodeIds, getRef)
}

func runInit(dockerCli *client.DockerCli, flags *pflag.FlagSet, opts initOptions) error {
	client := dockerCli.Client()
	ctx := context.Background()

	// If no secret was specified, we create a random one
	if !flags.Changed("secret") {
		opts.secret = generateRandomSecret()
		fmt.Fprintf(dockerCli.Out(), "No --secret provided. Generated random secret:\n\t%s\n\n", opts.secret)
	}

	req := swarm.InitRequest{
		ListenAddr:      opts.listenAddr.String(),
		ForceNewCluster: opts.forceNewCluster,
		Spec:            opts.swarmOptions.ToSpec(),
	}

	nodeID, err := client.SwarmInit(ctx, req)
	if err != nil {
		return err
	}

	fmt.Fprintf(dockerCli.Out(), "Swarm initialized: current node (%s) is now a manager.\n\n", nodeID)

	// Fetch CAHash and Address from the API
	info, err := client.Info(ctx)
	if err != nil {
		return err
	}

	node, _, err := client.NodeInspectWithRaw(ctx, nodeID)
	if err != nil {
		return err
	}

	if node.ManagerStatus != nil && info.Swarm.CACertHash != "" {
		var secretArgs string
		if opts.secret != "" {
			secretArgs = "--secret " + opts.secret
		}
		fmt.Fprintf(dockerCli.Out(), "To add a worker to this swarm, run the following command:\n\tdocker swarm join %s \\\n\t--ca-hash %s \\\n\t%s\n", secretArgs, info.Swarm.CACertHash, node.ManagerStatus.Addr)
	}

	return nil
}

func runPs(dockerCli *client.DockerCli, opts psOptions) error {
	client := dockerCli.Client()
	ctx := context.Background()

	nodeRef, err := Reference(ctx, client, opts.nodeID)
	if err != nil {
		return nil
	}
	node, _, err := client.NodeInspectWithRaw(ctx, nodeRef)
	if err != nil {
		return err
	}

	filter := opts.filter.Value()
	filter.Add("node", node.ID)
	tasks, err := client.TaskList(
		ctx,
		types.TaskListOptions{Filter: filter})
	if err != nil {
		return err
	}

	return task.Print(dockerCli, ctx, tasks, idresolver.New(client, opts.noResolve), opts.noTrunc)
}