func TestVersionMiddlewareWithErrors(t *testing.T) {
	handler := func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
		if httputils.VersionFromContext(ctx) == "" {
			t.Fatalf("Expected version, got empty string")
		}
		return nil
	}

	defaultVersion := version.Version("1.10.0")
	minVersion := version.Version("1.2.0")
	m := NewVersionMiddleware(defaultVersion.String(), defaultVersion, minVersion)
	h := m(handler)

	req, _ := http.NewRequest("GET", "/containers/json", nil)
	resp := httptest.NewRecorder()
	ctx := context.Background()

	vars := map[string]string{"version": "0.1"}
	err := h(ctx, resp, req, vars)

	if !strings.Contains(err.Error(), "client version 0.1 is too old. Minimum supported API version is 1.2.0") {
		t.Fatalf("Expected too old client error, got %v", err)
	}

	vars["version"] = "100000"
	err = h(ctx, resp, req, vars)
	if !strings.Contains(err.Error(), "client is newer than server") {
		t.Fatalf("Expected client newer than server error, got %v", err)
	}
}

func makeHttpHandler(eng *engine.Engine, logging bool, localMethod string, localRoute string, handlerFunc HttpApiFunc, enableCors bool, dockerVersion version.Version) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		// log the request
		utils.Debugf("Calling %s %s", localMethod, localRoute)

		if logging {
			log.Println(r.Method, r.RequestURI)
		}

		if strings.Contains(r.Header.Get("User-Agent"), "Docker-Client/") {
			userAgent := strings.Split(r.Header.Get("User-Agent"), "/")
			if len(userAgent) == 2 && !dockerVersion.Equal(version.Version(userAgent[1])) {
				utils.Debugf("Warning: client and server don't have the same version (client: %s, server: %s)", userAgent[1], dockerVersion)
			}
		}
		version := version.Version(mux.Vars(r)["version"])
		if version == "" {
			version = api.APIVERSION
		}
		if enableCors {
			writeCorsHeaders(w, r)
		}

		if version.GreaterThan(api.APIVERSION) {
			http.Error(w, fmt.Errorf("client and server don't have same version (client : %s, server: %s)", version, api.APIVERSION).Error(), http.StatusNotFound)
			return
		}

		if err := handlerFunc(eng, version, w, r, mux.Vars(r)); err != nil {
			utils.Errorf("Handler for %s %s returned error: %s", localMethod, localRoute, err)
			httpError(w, err)
		}
	}
}

// Update API Version in apiClient
func (e *Engine) updateClientVersionFromServer(serverVersion string) {
	// v will be >= 1.8, since this is checked earlier
	v := version.Version(serverVersion)
	switch {
	case v.LessThan(version.Version("1.9")):
		e.apiClient.UpdateClientVersion("1.20")
	case v.LessThan(version.Version("1.10")):
		e.apiClient.UpdateClientVersion("1.21")
	case v.LessThan(version.Version("1.11")):
		e.apiClient.UpdateClientVersion("1.22")
	default:
		e.apiClient.UpdateClientVersion("1.23")
	}
}

func createRouter(eng *engine.Engine, logging, enableCors bool, dockerVersion string) (*mux.Router, error) {
	r := mux.NewRouter()
	if os.Getenv("DEBUG") != "" {
		AttachProfiler(r)
	}

	for method, routes := range ServerRoutes {
		for route, fct := range routes {
			log.Debugf("Registering %s, %s", method, route)
			// NOTE: scope issue, make sure the variables are local and won't be changed
			localRoute := route
			localFct := fct
			localMethod := method

			// build the handler function
			f := makeHttpHandler(eng, logging, localMethod, localRoute, localFct, enableCors, version.Version(dockerVersion))

			// add the new route
			if localRoute == "" {
				r.Methods(localMethod).HandlerFunc(f)
			} else {
				r.Path("/v{version:[0-9.]+}" + localRoute).Methods(localMethod).HandlerFunc(f)
				r.Path(localRoute).Methods(localMethod).HandlerFunc(f)
			}
		}
	}

	return r, nil
}

func TestContext(t *testing.T) {
	ctx := Background()

	// First make sure getting non-existent values doesn't break
	if id := ctx.RequestID(); id != "" {
		t.Fatalf("RequestID() should have been '', was: %q", id)
	}

	if ver := ctx.Version(); ver != "" {
		t.Fatalf("Version() should have been '', was: %q", ver)
	}

	// Test basic set/get
	ctx = WithValue(ctx, RequestID, "123")
	if ctx.RequestID() != "123" {
		t.Fatalf("RequestID() should have been '123'")
	}

	// Now make sure after a 2nd set we can still get both
	ctx = WithValue(ctx, APIVersion, version.Version("x.y"))
	if id := ctx.RequestID(); id != "123" {
		t.Fatalf("RequestID() should have been '123', was %q", id)
	}
	if ver := ctx.Version(); ver != "x.y" {
		t.Fatalf("Version() should have been 'x.y', was %q", ver)
	}
}

func TestMiddlewares(t *testing.T) {
	cfg := &Config{
		Version: "0.1omega2",
	}
	srv := &Server{
		cfg: cfg,
	}

	srv.UseMiddleware(middleware.NewVersionMiddleware(version.Version("0.1omega2"), api.DefaultVersion, api.MinVersion))

	req, _ := http.NewRequest("GET", "/containers/json", nil)
	resp := httptest.NewRecorder()
	ctx := context.Background()

	localHandler := func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
		if httputils.VersionFromContext(ctx) == "" {
			t.Fatalf("Expected version, got empty string")
		}

		if sv := w.Header().Get("Server"); !strings.Contains(sv, "Docker/0.1omega2") {
			t.Fatalf("Expected server version in the header `Docker/0.1omega2`, got %s", sv)
		}

		return nil
	}

	handlerFunc := srv.handleWithGlobalMiddlewares(localHandler)
	if err := handlerFunc(ctx, resp, req, map[string]string{}); err != nil {
		t.Fatal(err)
	}
}

func makeRawConfigFromV1Config(imageJSON []byte, rootfs *image.RootFS, history []image.History) (map[string]*json.RawMessage, error) {
	var dver struct {
		DockerVersion string `json:"docker_version"`
	}

	if err := json.Unmarshal(imageJSON, &dver); err != nil {
		return nil, err
	}

	useFallback := versionPkg.Version(dver.DockerVersion).LessThan("1.8.3")

	if useFallback {
		var v1Image image.V1Image
		err := json.Unmarshal(imageJSON, &v1Image)
		if err != nil {
			return nil, err
		}
		imageJSON, err = json.Marshal(v1Image)
		if err != nil {
			return nil, err
		}
	}

	var c map[string]*json.RawMessage
	if err := json.Unmarshal(imageJSON, &c); err != nil {
		return nil, err
	}

	c["rootfs"] = rawJSON(rootfs)
	c["history"] = rawJSON(history)

	return c, nil
}

func TestAdjustCPUSharesOldApi(t *testing.T) {
	apiVersion := version.Version("1.18")
	hostConfig := &runconfig.HostConfig{
		CPUShares: linuxMinCPUShares - 1,
	}
	adjustCPUShares(apiVersion, hostConfig)
	if hostConfig.CPUShares != linuxMinCPUShares {
		t.Errorf("Expected CPUShares to be %d", linuxMinCPUShares)
	}

	hostConfig.CPUShares = linuxMaxCPUShares + 1
	adjustCPUShares(apiVersion, hostConfig)
	if hostConfig.CPUShares != linuxMaxCPUShares {
		t.Errorf("Expected CPUShares to be %d", linuxMaxCPUShares)
	}

	hostConfig.CPUShares = 0
	adjustCPUShares(apiVersion, hostConfig)
	if hostConfig.CPUShares != 0 {
		t.Error("Expected CPUShares to be unchanged")
	}

	hostConfig.CPUShares = 1024
	adjustCPUShares(apiVersion, hostConfig)
	if hostConfig.CPUShares != 1024 {
		t.Error("Expected CPUShares to be unchanged")
	}
}

func TestAdjustCpuSharesNoAdjustment(t *testing.T) {
	apiVersion := version.Version("1.19")
	hostConfig := &runconfig.HostConfig{
		CPUShares: linuxMinCpuShares - 1,
	}
	adjustCpuShares(apiVersion, hostConfig)
	if hostConfig.CPUShares != linuxMinCpuShares-1 {
		t.Errorf("Expected CpuShares to be %d", linuxMinCpuShares-1)
	}

	hostConfig.CPUShares = linuxMaxCpuShares + 1
	adjustCpuShares(apiVersion, hostConfig)
	if hostConfig.CPUShares != linuxMaxCpuShares+1 {
		t.Errorf("Expected CpuShares to be %d", linuxMaxCpuShares+1)
	}

	hostConfig.CPUShares = 0
	adjustCpuShares(apiVersion, hostConfig)
	if hostConfig.CPUShares != 0 {
		t.Error("Expected CpuShares to be unchanged")
	}

	hostConfig.CPUShares = 1024
	adjustCpuShares(apiVersion, hostConfig)
	if hostConfig.CPUShares != 1024 {
		t.Error("Expected CpuShares to be unchanged")
	}
}

func makeHttpHandler(logging bool, localMethod string, localRoute string, handlerFunc HttpApiFunc, corsHeaders string, dockerVersion version.Version) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		// log the request
		logrus.Debugf("Calling %s %s", localMethod, localRoute)

		if logging {
			logrus.Infof("%s %s", r.Method, r.RequestURI)
		}

		if strings.Contains(r.Header.Get("User-Agent"), "Docker-Client/") {
			userAgent := strings.Split(r.Header.Get("User-Agent"), "/")

			// v1.20 onwards includes the GOOS of the client after the version
			// such as Docker/1.7.0 (linux)
			if len(userAgent) == 2 && strings.Contains(userAgent[1], " ") {
				userAgent[1] = strings.Split(userAgent[1], " ")[0]
			}

			if len(userAgent) == 2 && !dockerVersion.Equal(version.Version(userAgent[1])) {
				logrus.Debugf("Warning: client and server don't have the same version (client: %s, server: %s)", userAgent[1], dockerVersion)
			}
		}
		version := version.Version(mux.Vars(r)["version"])
		if version == "" {
			version = api.Version
		}
		if corsHeaders != "" {
			writeCorsHeaders(w, r, corsHeaders)
		}

		if version.GreaterThan(api.Version) {
			http.Error(w, fmt.Errorf("client is newer than server (client API version: %s, server API version: %s)", version, api.Version).Error(), http.StatusBadRequest)
			return
		}
		if version.LessThan(api.MinVersion) {
			http.Error(w, fmt.Errorf("client is too old, minimum supported API version is %s, please upgrade your client to a newer version", api.MinVersion).Error(), http.StatusBadRequest)
			return
		}

		w.Header().Set("Server", "Docker/"+dockerversion.VERSION+" ("+runtime.GOOS+")")

		if err := handlerFunc(version, w, r, mux.Vars(r)); err != nil {
			logrus.Errorf("Handler for %s %s returned error: %s", localMethod, localRoute, err)
			httpError(w, err)
		}
	}
}

func (p *Pod) createNewContainers(daemon *Daemon, jsons []*dockertypes.ContainerJSON) error {

	var (
		ok  bool
		err error
		ccs dockertypes.ContainerCreateResponse
		rsp *dockertypes.ContainerJSON
		r   interface{}

		cleanup = func(id string) {
			if err != nil {
				glog.V(1).Infof("rollback container %s of %s", id, p.id)
				daemon.Daemon.ContainerRm(id, &dockertypes.ContainerRmConfig{})
			}
		}
	)

	for idx, c := range p.spec.Containers {
		if jsons[idx] != nil {
			glog.V(1).Infof("do not need to create container %s of pod %s[%d]", c.Name, p.id, idx)
			continue
		}

		config := &container.Config{
			Image:           c.Image,
			Cmd:             strslice.New(c.Command...),
			NetworkDisabled: true,
		}

		if len(c.Entrypoint) != 0 {
			config.Entrypoint = strslice.New(c.Entrypoint...)
		}

		ccs, err = daemon.Daemon.ContainerCreate(dockertypes.ContainerCreateConfig{
			Name:   c.Name,
			Config: config,
		})

		if err != nil {
			glog.Error(err.Error())
			return err
		}
		defer cleanup(ccs.ID)

		glog.Infof("create container %s", ccs.ID)
		if r, err = daemon.ContainerInspect(ccs.ID, false, version.Version("1.21")); err != nil {
			return err
		}

		if rsp, ok = r.(*dockertypes.ContainerJSON); !ok {
			err = fmt.Errorf("fail to unpack container json response for %s of %s", c.Name, p.id)
			return err
		}

		jsons[idx] = rsp
	}

	return nil
}

// Gather engine specs (CPU, memory, constraints, ...).
func (e *Engine) updateSpecs() error {
	info, err := e.client.Info()
	e.CheckConnectionErr(err)
	if err != nil {
		return err
	}

	if info.NCPU == 0 || info.MemTotal == 0 {
		return fmt.Errorf("cannot get resources for this engine, make sure %s is a Docker Engine, not a Swarm manager", e.Addr)
	}

	v, err := e.client.Version()
	e.CheckConnectionErr(err)
	if err != nil {
		return err
	}

	engineVersion := version.Version(v.Version)

	// Older versions of Docker don't expose the ID field, Labels and are not supported
	// by Swarm.  Catch the error ASAP and refuse to connect.
	if engineVersion.LessThan(minSupportedVersion) {
		err = fmt.Errorf("engine %s is running an unsupported version of Docker Engine. Please upgrade to at least %s", e.Addr, minSupportedVersion)
		e.CheckConnectionErr(err)
		return err
	}

	e.Lock()
	defer e.Unlock()
	// Swarm/docker identifies engine by ID. Updating ID but not updating cluster
	// index will put the cluster into inconsistent state. If this happens, the
	// engine should be put to pending state for re-validation.
	if e.ID == "" {
		e.ID = info.ID
	} else if e.ID != info.ID {
		e.state = statePending
		message := fmt.Sprintf("Engine (ID: %s, Addr: %s) shows up with another ID:%s. Please remove it from cluster, it can be added back.", e.ID, e.Addr, info.ID)
		e.lastError = message
		return fmt.Errorf(message)
	}
	e.Name = info.Name
	e.Cpus = info.NCPU
	e.Memory = info.MemTotal
	e.Labels = map[string]string{
		"storagedriver":   info.Driver,
		"executiondriver": info.ExecutionDriver,
		"kernelversion":   info.KernelVersion,
		"operatingsystem": info.OperatingSystem,
	}
	for _, label := range info.Labels {
		kv := strings.SplitN(label, "=", 2)
		if len(kv) != 2 {
			message := fmt.Sprintf("Engine (ID: %s, Addr: %s) contains an invalid label (%s) not formatted as \"key=value\".", e.ID, e.Addr, label)
			return fmt.Errorf(message)
		}
		e.Labels[kv[0]] = kv[1]
	}
	return nil
}

// CmdVersion shows Docker version information.
//
// Available version information is shown for: client Docker version, client API version, client Go version, client Git commit, client OS/Arch, server Docker version, server API version, server Go version, server Git commit, and server OS/Arch.
//
// Usage: docker version
func (cli *DockerCli) CmdVersion(args ...string) (err error) {
	cmd := Cli.Subcmd("version", nil, Cli.DockerCommands["version"].Description, true)
	tmplStr := cmd.String([]string{"f", "#format", "-format"}, "", "Format the output using the given go template")
	cmd.Require(flag.Exact, 0)

	cmd.ParseFlags(args, true)

	templateFormat := versionTemplate
	if *tmplStr != "" {
		templateFormat = *tmplStr
	}

	var tmpl *template.Template
	if tmpl, err = template.New("").Funcs(funcMap).Parse(templateFormat); err != nil {
		return Cli.StatusError{StatusCode: 64,
			Status: "Template parsing error: " + err.Error()}
	}

	vd := types.VersionResponse{
		Client: &types.Version{
			Version:      dockerversion.Version,
			APIVersion:   version.Version(cli.client.ClientVersion()),
			GoVersion:    runtime.Version(),
			GitCommit:    dockerversion.GitCommit,
			BuildTime:    dockerversion.BuildTime,
			Os:           runtime.GOOS,
			Arch:         runtime.GOARCH,
			Experimental: utils.ExperimentalBuild(),
		},
	}

	serverVersion, err := cli.client.ServerVersion()
	if err == nil {
		vd.Server = &serverVersion
	}

	// first we need to make BuildTime more human friendly
	t, errTime := time.Parse(time.RFC3339Nano, vd.Client.BuildTime)
	if errTime == nil {
		vd.Client.BuildTime = t.Format(time.ANSIC)
	}

	if vd.ServerOK() {
		t, errTime = time.Parse(time.RFC3339Nano, vd.Server.BuildTime)
		if errTime == nil {
			vd.Server.BuildTime = t.Format(time.ANSIC)
		}
	}

	if err2 := tmpl.Execute(cli.out, vd); err2 != nil && err == nil {
		err = err2
	}
	cli.out.Write([]byte{'\n'})
	return err
}

// userAgentMiddleware checks the User-Agent header looking for a valid docker client spec.
func (s *Server) userAgentMiddleware(handler httputils.APIFunc) httputils.APIFunc {
	return func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
		if strings.Contains(r.Header.Get("User-Agent"), "Docker-Client/") {
			dockerVersion := version.Version(s.cfg.Version)

			userAgent := strings.Split(r.Header.Get("User-Agent"), "/")

			// v1.20 onwards includes the GOOS of the client after the version
			// such as Docker/1.7.0 (linux)
			if len(userAgent) == 2 && strings.Contains(userAgent[1], " ") {
				userAgent[1] = strings.Split(userAgent[1], " ")[0]
			}

			if len(userAgent) == 2 && !dockerVersion.Equal(version.Version(userAgent[1])) {
				logrus.Warnf("Warning: client and server don't have the same version (client: %s, server: %s)", userAgent[1], dockerVersion)
			}
		}
		return handler(ctx, w, r, vars)
	}
}

func TestVersionMiddleware(t *testing.T) {
	handler := func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
		if httputils.VersionFromContext(ctx) == "" {
			t.Fatalf("Expected version, got empty string")
		}
		return nil
	}

	defaultVersion := version.Version("1.10.0")
	minVersion := version.Version("1.2.0")
	m := NewVersionMiddleware(defaultVersion.String(), defaultVersion, minVersion)
	h := m(handler)

	req, _ := http.NewRequest("GET", "/containers/json", nil)
	resp := httptest.NewRecorder()
	ctx := context.Background()
	if err := h(ctx, resp, req, map[string]string{}); err != nil {
		t.Fatal(err)
	}
}

// Version is a utility func to make it easier to get the
// API version string associated with this Context/request.
func (ctx Context) Version() version.Version {
	val := ctx.Value(APIVersion)
	if val == nil {
		return version.Version("")
	}

	ver, ok := val.(version.Version)
	if !ok {
		// Ideally we shouldn't panic but we also should never get here
		panic("Context APIVersion isn't a version.Version")
	}
	return ver
}

func (c *Container) createByEngine() (*dockertypes.ContainerJSON, error) {
	var (
		ok  bool
		err error
		ccs dockertypes.ContainerCreateResponse
		rsp *dockertypes.ContainerJSON
		r   interface{}
	)

	config := &container.Config{
		Image:           c.spec.Image,
		Cmd:             strslice.New(c.spec.Command...),
		NetworkDisabled: true,
	}

	if len(c.spec.Entrypoint) != 0 {
		config.Entrypoint = strslice.New(c.spec.Entrypoint...)
	}

	if len(c.spec.Envs) != 0 {
		envs := []string{}
		for _, env := range c.spec.Envs {
			envs = append(envs, env.Env+"="+env.Value)
		}
		config.Env = envs
	}

	ccs, err = c.p.factory.engine.ContainerCreate(dockertypes.ContainerCreateConfig{
		Name:   c.spec.Name,
		Config: config,
	})

	if err != nil {
		return nil, err
	}

	c.Log(INFO, "create container %s (w/: %s)", ccs.ID, ccs.Warnings)
	if r, err = c.p.factory.engine.ContainerInspect(ccs.ID, false, version.Version("1.21")); err != nil {
		return nil, err
	}

	if rsp, ok = r.(*dockertypes.ContainerJSON); !ok {
		err = fmt.Errorf("fail to unpack container json response for %s of %s", c.spec.Name, c.p.Id())
		return nil, err
	}

	c.spec.Id = ccs.ID
	c.updateLogPrefix()
	return rsp, nil
}

// NewVersionMiddleware creates a new Version middleware.
func NewVersionMiddleware(versionCheck string, defaultVersion, minVersion version.Version) Middleware {
	serverVersion := version.Version(versionCheck)

	return func(handler httputils.APIFunc) httputils.APIFunc {
		return func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
			apiVersion := version.Version(vars["version"])
			if apiVersion == "" {
				apiVersion = defaultVersion
			}

			if apiVersion.GreaterThan(defaultVersion) {
				return badRequestError{fmt.Errorf("client is newer than server (client API version: %s, server API version: %s)", apiVersion, defaultVersion)}
			}
			if apiVersion.LessThan(minVersion) {
				return badRequestError{fmt.Errorf("client version %s is too old. Minimum supported API version is %s, please upgrade your client to a newer version", apiVersion, minVersion)}
			}

			header := fmt.Sprintf("Docker/%s (%s)", serverVersion, runtime.GOOS)
			w.Header().Set("Server", header)
			ctx = context.WithValue(ctx, httputils.APIVersionKey, apiVersion)
			return handler(ctx, w, r, vars)
		}
	}
}

// NewUserAgentMiddleware creates a new UserAgent middleware.
func NewUserAgentMiddleware(versionCheck string) Middleware {
	serverVersion := version.Version(versionCheck)

	return func(handler httputils.APIFunc) httputils.APIFunc {
		return func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
			ctx = context.WithValue(ctx, httputils.UAStringKey, r.Header.Get("User-Agent"))

			if strings.Contains(r.Header.Get("User-Agent"), "Docker-Client/") {
				userAgent := strings.Split(r.Header.Get("User-Agent"), "/")

				// v1.20 onwards includes the GOOS of the client after the version
				// such as Docker/1.7.0 (linux)
				if len(userAgent) == 2 && strings.Contains(userAgent[1], " ") {
					userAgent[1] = strings.Split(userAgent[1], " ")[0]
				}

				if len(userAgent) == 2 && !serverVersion.Equal(version.Version(userAgent[1])) {
					logrus.Debugf("Client and server don't have the same version (client: %s, server: %s)", userAgent[1], serverVersion)
				}
			}
			return handler(ctx, w, r, vars)
		}
	}
}

// NewVersionMiddleware creates a new Version middleware.
func NewVersionMiddleware(versionCheck string, defaultVersion, minVersion version.Version) Middleware {
	serverVersion := version.Version(versionCheck)

	return func(handler httputils.APIFunc) httputils.APIFunc {
		return func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
			apiVersion := version.Version(vars["version"])
			if apiVersion == "" {
				apiVersion = defaultVersion
			}

			if apiVersion.GreaterThan(defaultVersion) {
				return errors.ErrorCodeNewerClientVersion.WithArgs(apiVersion, defaultVersion)
			}
			if apiVersion.LessThan(minVersion) {
				return errors.ErrorCodeOldClientVersion.WithArgs(apiVersion, minVersion)
			}

			header := fmt.Sprintf("Docker/%s (%s)", serverVersion, runtime.GOOS)
			w.Header().Set("Server", header)
			ctx = context.WithValue(ctx, httputils.APIVersionKey, apiVersion)
			return handler(ctx, w, r, vars)
		}
	}
}