feat(contrib): add eureka registry (#1792) (#1793)

* - feat(contrib): add eureka registry (#1792)


Co-authored-by: fangyong <fangyong@haodf.com>

contrib/registry/eureka/client.go

@@ -0,0 +1,347 @@
+package eureka
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"math/rand"
+	"net/http"
+	"strings"
+	"sync"
+	"time"
+)
+
+const (
+	statusUp            = "UP"
+	statusDown          = "DOWN"
+	statusOutOfServeice = "OUT_OF_SERVICE"
+	heartbeatRetry      = 3
+	maxIdleConns        = 100
+	heartbeatTime       = 10
+	httpTimeout         = 3
+	refreshTime         = 30
+)
+
+type Endpoint struct {
+	InstanceID     string
+	IP             string
+	AppID          string
+	Port           int
+	SecurePort     int
+	HomePageURL    string
+	StatusPageURL  string
+	HealthCheckURL string
+	MetaData       map[string]string
+}
+
+// Response for /eureka/apps
+type ApplicationsRootResponse struct {
+	ApplicationsResponse `json:"applications"`
+}
+
+type ApplicationsResponse struct {
+	Version      string        `json:"versions__delta"`
+	AppsHashcode string        `json:"apps__hashcode"`
+	Applications []Application `json:"application"`
+}
+
+type Application struct {
+	Name     string     `json:"name"`
+	Instance []Instance `json:"instance"`
+}
+
+type RequestInstance struct {
+	Instance Instance `json:"instance"`
+}
+
+type Instance struct {
+	InstanceID     string            `json:"instanceId"`
+	HostName       string            `json:"hostName"`
+	Port           Port              `json:"port"`
+	App            string            `json:"app"`
+	IPAddr         string            `json:"ipAddr"`
+	VipAddress     string            `json:"vipAddress"`
+	Status         string            `json:"status"`
+	SecurePort     Port              `json:"securePort"`
+	HomePageURL    string            `json:"homePageUrl"`
+	StatusPageURL  string            `json:"statusPageUrl"`
+	HealthCheckURL string            `json:"healthCheckUrl"`
+	DataCenterInfo DataCenterInfo    `json:"dataCenterInfo"`
+	Metadata       map[string]string `json:"metadata"`
+}
+
+type Port struct {
+	Port    int    `json:"$"`
+	Enabled string `json:"@enabled"`
+}
+
+type DataCenterInfo struct {
+	Name  string `json:"name"`
+	Class string `json:"@class"`
+}
+
+var _ APIInterface = new(Client)
+
+type APIInterface interface {
+	Register(ctx context.Context, ep Endpoint) error
+	Deregister(ctx context.Context, appID, instanceID string) error
+	Heartbeat(ep Endpoint)
+	FetchApps(ctx context.Context) []Application
+	FetchAllUpInstances(ctx context.Context) []Instance
+	FetchAppInstances(ctx context.Context, appID string) (m Application, err error)
+	FetchAppUpInstances(ctx context.Context, appID string) []Instance
+	FetchAppInstance(ctx context.Context, appID string, instanceID string) (m Instance, err error)
+	FetchInstance(ctx context.Context, instanceID string) (m Instance, err error)
+	Out(ctx context.Context, appID, instanceID string) error
+	Down(ctx context.Context, appID, instanceID string) error
+}
+
+type ClientOption func(e *Client)
+
+func WithMaxRetry(maxRetry int) ClientOption {
+	return func(e *Client) { e.maxRetry = maxRetry }
+}
+
+func WithHeartbeatInterval(interval time.Duration) ClientOption {
+	return func(e *Client) {
+		e.heartbeatInterval = interval
+	}
+}
+
+func WithClientContext(ctx context.Context) ClientOption {
+	return func(e *Client) { e.ctx = ctx }
+}
+
+func WithNamespace(path string) ClientOption {
+	return func(e *Client) { e.eurekaPath = path }
+}
+
+type Client struct {
+	ctx               context.Context
+	urls              []string
+	eurekaPath        string
+	maxRetry          int
+	heartbeatInterval time.Duration
+	client            *http.Client
+	keepalive         map[string]chan struct{}
+	lock              sync.Mutex
+}
+
+func NewClient(urls []string, opts ...ClientOption) *Client {
+	tr := &http.Transport{
+		MaxIdleConns: maxIdleConns,
+	}
+
+	e := &Client{
+		ctx:               context.Background(),
+		urls:              urls,
+		eurekaPath:        "eureka/v2",
+		maxRetry:          len(urls),
+		heartbeatInterval: time.Second * heartbeatTime,
+		client:            &http.Client{Transport: tr, Timeout: time.Second * httpTimeout},
+		keepalive:         make(map[string]chan struct{}),
+	}
+
+	for _, o := range opts {
+		o(e)
+	}
+
+	return e
+}
+
+func (e *Client) FetchApps(ctx context.Context) []Application {
+	var m ApplicationsRootResponse
+	if err := e.do(ctx, "GET", []string{"apps"}, nil, &m); err != nil {
+		return nil
+	}
+
+	return m.Applications
+}
+
+func (e *Client) FetchAppInstances(ctx context.Context, appID string) (m Application, err error) {
+	err = e.do(ctx, "GET", []string{"apps", appID}, nil, &m)
+	return
+}
+
+func (e *Client) FetchAppUpInstances(ctx context.Context, appID string) []Instance {
+	app, err := e.FetchAppInstances(ctx, appID)
+	if err != nil {
+		return nil
+	}
+	return e.filterUp(app)
+}
+
+func (e *Client) FetchAppInstance(ctx context.Context, appID string, instanceID string) (m Instance, err error) {
+	err = e.do(ctx, "GET", []string{"apps", appID, instanceID}, nil, &m)
+	return
+}
+
+func (e *Client) FetchInstance(ctx context.Context, instanceID string) (m Instance, err error) {
+	err = e.do(ctx, "GET", []string{"instances", instanceID}, nil, &m)
+	return
+}
+
+func (e *Client) Out(ctx context.Context, appID, instanceID string) error {
+	return e.do(ctx, "PUT", []string{"apps", appID, instanceID, fmt.Sprintf("status?value=%s", statusOutOfServeice)}, nil, nil)
+}
+
+func (e *Client) Down(ctx context.Context, appID, instanceID string) error {
+	return e.do(ctx, "PUT", []string{"apps", appID, instanceID, fmt.Sprintf("status?value=%s", statusDown)}, nil, nil)
+}
+
+func (e *Client) FetchAllUpInstances(ctx context.Context) []Instance {
+	return e.filterUp(e.FetchApps(ctx)...)
+}
+
+func (e *Client) Register(ctx context.Context, ep Endpoint) error {
+	return e.registerEndpoint(ctx, ep)
+}
+
+func (e *Client) Deregister(ctx context.Context, appID, instanceID string) error {
+	if err := e.do(ctx, "DELETE", []string{"apps", appID, instanceID}, nil, nil); err != nil {
+		return err
+	}
+	go e.cancelHeartbeat(appID)
+	return nil
+}
+
+func (e *Client) registerEndpoint(ctx context.Context, ep Endpoint) error {
+	instance := RequestInstance{
+		Instance: Instance{
+			InstanceID: ep.InstanceID,
+			HostName:   ep.AppID,
+			Port: Port{
+				Port:    ep.Port,
+				Enabled: "true",
+			},
+			App:        ep.AppID,
+			IPAddr:     ep.IP,
+			VipAddress: ep.AppID,
+			Status:     statusUp,
+			SecurePort: Port{
+				Port:    ep.SecurePort,
+				Enabled: "false",
+			},
+			HomePageURL:    ep.HomePageURL,
+			StatusPageURL:  ep.StatusPageURL,
+			HealthCheckURL: ep.HealthCheckURL,
+			DataCenterInfo: DataCenterInfo{
+				Name:  "MyOwn",
+				Class: "com.netflix.appinfo.InstanceInfo$DefaultDataCenterInfo",
+			},
+			Metadata: ep.MetaData,
+		},
+	}
+
+	body, err := json.Marshal(instance)
+	if err != nil {
+		return err
+	}
+	return e.do(ctx, "POST", []string{"apps", ep.AppID}, bytes.NewReader(body), nil)
+}
+
+func (e *Client) Heartbeat(ep Endpoint) {
+	e.lock.Lock()
+	e.keepalive[ep.AppID] = make(chan struct{})
+	e.lock.Unlock()
+
+	ticker := time.NewTicker(e.heartbeatInterval)
+	defer ticker.Stop()
+	retryCount := 0
+	for {
+		select {
+		case <-e.ctx.Done():
+			return
+		case <-e.keepalive[ep.AppID]:
+			return
+		case <-ticker.C:
+			if err := e.do(e.ctx, "PUT", []string{"apps", ep.AppID, ep.InstanceID}, nil, nil); err != nil {
+				if retryCount++; retryCount > heartbeatRetry {
+					_ = e.registerEndpoint(e.ctx, ep)
+					retryCount = 0
+				}
+			}
+		}
+	}
+}
+
+func (e *Client) cancelHeartbeat(appID string) {
+	defer e.lock.Unlock()
+	e.lock.Lock()
+	if ch, ok := e.keepalive[appID]; ok {
+		ch <- struct{}{}
+	}
+}
+
+func (e *Client) filterUp(apps ...Application) (res []Instance) {
+	for _, app := range apps {
+		for _, ins := range app.Instance {
+			if ins.Status == statusUp {
+				res = append(res, ins)
+			}
+		}
+	}
+
+	return
+}
+
+func (e *Client) pickServer(currentTimes int) string {
+	return e.urls[currentTimes%e.maxRetry]
+}
+
+func (e *Client) shuffle() {
+	rand.Seed(time.Now().UnixNano())
+	rand.Shuffle(len(e.urls), func(i, j int) {
+		e.urls[i], e.urls[j] = e.urls[j], e.urls[i]
+	})
+}
+
+func (e *Client) buildAPI(currentTimes int, params ...string) string {
+	if currentTimes == 0 {
+		e.shuffle()
+	}
+	server := e.pickServer(currentTimes)
+	params = append([]string{server, e.eurekaPath}, params...)
+	return strings.Join(params, "/")
+}
+
+func (e *Client) do(ctx context.Context, method string, params []string, input io.Reader, output interface{}) error {
+	for i := 0; i < e.maxRetry; i++ {
+		request, err := http.NewRequest(method, e.buildAPI(i, params...), input)
+		if err != nil {
+			return err
+		}
+		request = request.WithContext(ctx)
+		request.Header.Add("User-Agent", "go-eureka-client")
+		request.Header.Add("Accept", "application/json;charset=UTF-8")
+		request.Header.Add("Content-Type", "application/json;charset=UTF-8")
+		resp, err := e.client.Do(request)
+		if err != nil {
+			continue
+		}
+		defer func() {
+			_, _ = io.Copy(ioutil.Discard, resp.Body)
+			resp.Body.Close()
+		}()
+
+		if output != nil && resp.StatusCode/100 == 2 {
+			data, err := ioutil.ReadAll(resp.Body)
+			if err != nil {
+				return err
+			}
+			if err = json.Unmarshal(data, output); err != nil {
+				return err
+			}
+		}
+
+		if resp.StatusCode >= http.StatusBadRequest {
+			return fmt.Errorf("response Error %d", resp.StatusCode)
+		}
+
+		return nil
+	}
+	return fmt.Errorf("retry after %d times", e.maxRetry)
+}

contrib/registry/eureka/eureka.go

@@ -0,0 +1,136 @@
+package eureka
+
+import (
+	"context"
+	"strings"
+	"sync"
+	"time"
+)
+
+type subscriber struct {
+	appID    string
+	callBack func()
+}
+
+type API struct {
+	cli             *Client
+	allInstances    map[string][]Instance
+	subscribers     map[string]*subscriber
+	refreshInterval time.Duration
+	lock            sync.Mutex
+}
+
+func NewAPI(ctx context.Context, client *Client, refreshInterval time.Duration) *API {
+	e := &API{
+		cli:             client,
+		allInstances:    make(map[string][]Instance),
+		subscribers:     make(map[string]*subscriber),
+		refreshInterval: refreshInterval,
+	}
+
+	// 首次广播一次
+	e.broadcast()
+
+	go e.refresh(ctx)
+
+	return e
+}
+
+func (e *API) refresh(ctx context.Context) {
+	ticker := time.NewTicker(e.refreshInterval)
+	defer ticker.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-ticker.C:
+			e.broadcast()
+		}
+	}
+}
+
+func (e *API) broadcast() {
+	instances := e.cacheAllInstances()
+	if instances == nil {
+		return
+	}
+
+	for _, subscriber := range e.subscribers {
+		go subscriber.callBack()
+	}
+	defer e.lock.Unlock()
+	e.lock.Lock()
+	e.allInstances = instances
+}
+
+func (e *API) cacheAllInstances() map[string][]Instance {
+	items := make(map[string][]Instance)
+	instances := e.cli.FetchAllUpInstances(context.Background())
+	for _, instance := range instances {
+		items[e.ToAppID(instance.App)] = append(items[instance.App], instance)
+	}
+
+	return items
+}
+
+func (e *API) Register(ctx context.Context, serviceName string, endpoints ...Endpoint) error {
+	appID := e.ToAppID(serviceName)
+	upInstances := make(map[string]struct{})
+
+	for _, ins := range e.GetService(ctx, appID) {
+		upInstances[ins.InstanceID] = struct{}{}
+	}
+
+	for _, ep := range endpoints {
+		if _, ok := upInstances[ep.InstanceID]; !ok {
+			if err := e.cli.Register(ctx, ep); err != nil {
+				return err
+			}
+			go e.cli.Heartbeat(ep)
+		}
+	}
+
+	return nil
+}
+
+// Deregister 中的ctx 和 register ctx 是同一个
+func (e *API) Deregister(ctx context.Context, endpoints []Endpoint) error {
+	for _, ep := range endpoints {
+		if err := e.cli.Deregister(ctx, ep.AppID, ep.InstanceID); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (e *API) Subscribe(serverName string, fn func()) error {
+	e.lock.Lock()
+	defer e.lock.Unlock()
+	appID := e.ToAppID(serverName)
+	e.subscribers[appID] = &subscriber{
+		appID:    appID,
+		callBack: fn,
+	}
+	return nil
+}
+
+func (e *API) GetService(ctx context.Context, serverName string) []Instance {
+	appID := e.ToAppID(serverName)
+	if ins, ok := e.allInstances[appID]; ok {
+		return ins
+	}
+
+	// 如果不再allinstances 中可以尝试再单独获取一次
+	return e.cli.FetchAppUpInstances(ctx, appID)
+}
+
+func (e *API) Unsubscribe(serverName string) {
+	e.lock.Lock()
+	defer e.lock.Unlock()
+	delete(e.subscribers, e.ToAppID(serverName))
+}
+
+func (e *API) ToAppID(serverName string) string {
+	return strings.ToUpper(serverName)
+}

contrib/registry/eureka/go.mod

@@ -0,0 +1,7 @@
+module github.com/go-kratos/kratos/contrib/registry/eureka/v2
+
+go 1.16
+
+require github.com/go-kratos/kratos/v2 v2.1.5
+
+replace github.com/go-kratos/kratos/v2 => ../../../

contrib/registry/eureka/go.sum

@@ -0,0 +1,154 @@
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contrib/registry/eureka/register.go

@@ -0,0 +1,146 @@
+package eureka
+
+import (
+	"context"
+	"fmt"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/go-kratos/kratos/v2/registry"
+)
+
+var (
+	_ registry.Registrar = &Registry{}
+	_ registry.Discovery = &Registry{}
+)
+
+type Option func(o *Registry)
+
+// WithContext with registry context.
+func WithContext(ctx context.Context) Option {
+	return func(o *Registry) { o.ctx = ctx }
+}
+
+func WithHeartbeat(interval time.Duration) Option {
+	return func(o *Registry) { o.heartbeatInterval = interval }
+}
+
+func WithRefresh(interval time.Duration) Option {
+	return func(o *Registry) { o.refreshInterval = interval }
+}
+
+func WithEurekaPath(path string) Option {
+	return func(o *Registry) { o.eurekaPath = path }
+}
+
+type Registry struct {
+	ctx               context.Context
+	api               *API
+	heartbeatInterval time.Duration
+	refreshInterval   time.Duration
+	eurekaPath        string
+}
+
+func New(eurekaUrls []string, opts ...Option) (*Registry, error) {
+	r := &Registry{
+		ctx:               context.Background(),
+		heartbeatInterval: heartbeatTime,
+		refreshInterval:   refreshTime,
+		eurekaPath:        "eureka/v2",
+	}
+
+	for _, o := range opts {
+		o(r)
+	}
+
+	client := NewClient(eurekaUrls, WithHeartbeatInterval(r.heartbeatInterval), WithClientContext(r.ctx), WithNamespace(r.eurekaPath))
+	r.api = NewAPI(r.ctx, client, r.refreshInterval)
+	return r, nil
+}
+
+// 这里的Context是每个注册器独享的
+func (r *Registry) Register(ctx context.Context, service *registry.ServiceInstance) error {
+	return r.api.Register(ctx, service.Name, r.Endpoints(service)...)
+}
+
+// Deregister registry service to zookeeper.
+func (r *Registry) Deregister(ctx context.Context, service *registry.ServiceInstance) error {
+	return r.api.Deregister(ctx, r.Endpoints(service))
+}
+
+// GetService get services from zookeeper
+func (r *Registry) GetService(ctx context.Context, serviceName string) ([]*registry.ServiceInstance, error) {
+	instances := r.api.GetService(ctx, serviceName)
+	items := make([]*registry.ServiceInstance, 0, len(instances))
+	for _, instance := range instances {
+		items = append(items, &registry.ServiceInstance{
+			ID:        instance.Metadata["ID"],
+			Name:      instance.Metadata["Name"],
+			Version:   instance.Metadata["Version"],
+			Endpoints: []string{instance.Metadata["Endpoints"]},
+			Metadata:  instance.Metadata,
+		})
+	}
+
+	return items, nil
+}
+
+// watch 是独立的ctx
+func (r *Registry) Watch(ctx context.Context, serviceName string) (registry.Watcher, error) {
+	return newWatch(ctx, r.api, serviceName)
+}
+
+func (r *Registry) Endpoints(service *registry.ServiceInstance) []Endpoint {
+	var (
+		res   = []Endpoint{}
+		start int
+	)
+	for _, ep := range service.Endpoints {
+		start = strings.Index(ep, "//")
+		end := strings.LastIndex(ep, ":")
+		appID := strings.ToUpper(service.Name)
+		ip := ep[start+2 : end]
+		sport := ep[end+1:]
+		port, _ := strconv.Atoi(sport)
+		securePort := 443
+		homePageURL := fmt.Sprintf("%s/", ep)
+		statusPageURL := fmt.Sprintf("%s/info", ep)
+		healthCheckURL := fmt.Sprintf("%s/health", ep)
+		instanceID := strings.Join([]string{ip, appID, sport}, ":")
+		metadata := make(map[string]string)
+		if len(service.Metadata) > 0 {
+			metadata = service.Metadata
+		}
+		if s, ok := service.Metadata["securePort"]; ok {
+			securePort, _ = strconv.Atoi(s)
+		}
+		if s, ok := service.Metadata["homePageURL"]; ok {
+			homePageURL = s
+		}
+		if s, ok := service.Metadata["statusPageURL"]; ok {
+			statusPageURL = s
+		}
+		if s, ok := service.Metadata["healthCheckURL"]; ok {
+			healthCheckURL = s
+		}
+		metadata["ID"] = service.ID
+		metadata["Name"] = service.Name
+		metadata["Version"] = service.Version
+		metadata["Endpoints"] = ep
+		metadata["agent"] = "go-eureka-client"
+		res = append(res, Endpoint{
+			AppID:          appID,
+			IP:             ip,
+			Port:           port,
+			SecurePort:     securePort,
+			HomePageURL:    homePageURL,
+			StatusPageURL:  statusPageURL,
+			HealthCheckURL: healthCheckURL,
+			InstanceID:     instanceID,
+			MetaData:       metadata,
+		})
+	}
+
+	return res
+}

contrib/registry/eureka/register_test.go

@@ -0,0 +1,114 @@
+package eureka
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/go-kratos/kratos/v2/registry"
+)
+
+func TestRegistry(t *testing.T) {
+	ctx := context.Background()
+	ctx, cancel := context.WithCancel(ctx)
+	s1 := &registry.ServiceInstance{
+		ID:        "0",
+		Name:      "helloworld",
+		Endpoints: []string{"http://127.0.0.1:1111"},
+	}
+	s2 := &registry.ServiceInstance{
+		ID:        "0",
+		Name:      "helloworld2",
+		Endpoints: []string{"http://127.0.0.1:222"},
+	}
+
+	r, _ := New([]string{"https://127.0.0.1:18761"}, WithContext(ctx), WithHeartbeat(time.Second), WithRefresh(time.Second), WithEurekaPath("eureka"))
+
+	go do(r, s1)
+	go do(r, s2)
+
+	time.Sleep(time.Second * 20)
+	cancel()
+	time.Sleep(time.Second * 1)
+}
+
+func do(r *Registry, s *registry.ServiceInstance) {
+	w, err := r.Watch(context.Background(), s.Name)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer func() {
+		_ = w.Stop()
+	}()
+	go func() {
+		for {
+			res, nextErr := w.Next()
+			if nextErr != nil {
+				return
+			}
+			log.Printf("watch: %d", len(res))
+			for _, r := range res {
+				log.Printf("next: %+v", r)
+			}
+		}
+	}()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	if err = r.Register(ctx, s); err != nil {
+		log.Fatal(err)
+	}
+
+	time.Sleep(time.Second * 10)
+	res, err := r.GetService(ctx, s.Name)
+	if err != nil {
+		log.Fatal(err)
+	}
+	for i, re := range res {
+		log.Printf("first %d re:%v\n", i, re)
+	}
+
+	if len(res) != 1 && res[0].Name != s.Name {
+		log.Fatalf("not expected: %+v", res)
+	}
+
+	if err = r.Deregister(ctx, s); err != nil {
+		log.Fatal(err)
+	}
+	cancel()
+	time.Sleep(time.Second * 10)
+
+	res, err = r.GetService(ctx, s.Name)
+	if err != nil {
+		log.Fatal(err)
+	}
+	for i, re := range res {
+		log.Printf("second %d re:%v\n", i, re)
+	}
+	if len(res) != 0 {
+		log.Fatalf("not expected empty")
+	}
+}
+
+func TestLock(t *testing.T) {
+	type me struct {
+		lock sync.Mutex
+	}
+
+	a := &me{}
+	go func() {
+		defer a.lock.Unlock()
+		a.lock.Lock()
+		fmt.Println("This is fmt first.")
+		time.Sleep(time.Second * 5)
+	}()
+	go func() {
+		defer a.lock.Unlock()
+		a.lock.Lock()
+		fmt.Println("This is fmt second.")
+		time.Sleep(time.Second * 5)
+	}()
+	time.Sleep(time.Second * 10)
+}

contrib/registry/eureka/watcher.go

@@ -0,0 +1,60 @@
+package eureka
+
+import (
+	"context"
+
+	"github.com/go-kratos/kratos/v2/registry"
+)
+
+var _ registry.Watcher = &watcher{}
+
+type watcher struct {
+	ctx        context.Context
+	cancel     context.CancelFunc
+	cli        *API
+	watchChan  chan struct{}
+	serverName string
+}
+
+func newWatch(ctx context.Context, cli *API, serverName string) (*watcher, error) {
+	w := &watcher{
+		ctx:        ctx,
+		cli:        cli,
+		serverName: serverName,
+		watchChan:  make(chan struct{}, 1),
+	}
+	w.ctx, w.cancel = context.WithCancel(ctx)
+	e := w.cli.Subscribe(
+		serverName,
+		func() {
+			w.watchChan <- struct{}{}
+		},
+	)
+	return w, e
+}
+
+func (w watcher) Next() (services []*registry.ServiceInstance, err error) {
+	select {
+	case <-w.ctx.Done():
+		return nil, w.ctx.Err()
+	case <-w.watchChan:
+		instances := w.cli.GetService(w.ctx, w.serverName)
+		services = make([]*registry.ServiceInstance, 0, len(instances))
+		for _, instance := range instances {
+			services = append(services, &registry.ServiceInstance{
+				ID:        instance.Metadata["ID"],
+				Name:      instance.Metadata["Name"],
+				Version:   instance.Metadata["Version"],
+				Endpoints: []string{instance.Metadata["Endpoints"]},
+				Metadata:  instance.Metadata,
+			})
+		}
+		return
+	}
+}
+
+func (w *watcher) Stop() error {
+	w.cancel()
+	w.cli.Unsubscribe(w.serverName)
+	return nil
+}

hack/.test_ignored_files

@@ -7,3 +7,4 @@
 ./contrib/registry/zookeeper
 ./contrib/registry/etcd
 ./contrib/registry/consul
+./contrib/registry/eureka