fix: delay to start the metric server port (#36080)

- issue: #36083
/kind improvement

Signed-off-by: SimFG <bang.fu@zilliz.com>

cmd/roles/roles.go

@@ -30,6 +30,7 @@ import (
 
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
+	"github.com/samber/lo"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
 
@@ -385,6 +386,21 @@ func (mr *MilvusRoles) Run() {
 		defer streaming.Release()
 	}
 
+	enableComponents := []bool{
+		mr.EnableRootCoord,
+		mr.EnableProxy,
+		mr.EnableQueryCoord,
+		mr.EnableQueryNode,
+		mr.EnableDataCoord,
+		mr.EnableDataNode,
+		mr.EnableIndexCoord,
+		mr.EnableIndexNode,
+	}
+	enableComponents = lo.Filter(enableComponents, func(v bool, _ int) bool {
+		return v
+	})
+	healthz.SetComponentNum(len(enableComponents))
+
 	expr.Init()
 	expr.Register("param", paramtable.Get())
 	mr.setupLogger()

internal/http/healthz/healthz_handler.go

@@ -52,7 +52,8 @@ type HealthResponse struct {
 }
 
 type HealthHandler struct {
-	indicators []Indicator
+	indicators   []Indicator
+	indicatorNum int
 
 	// unregister role when call stop by restful api
 	unregisterLock    sync.RWMutex
@@ -67,6 +68,10 @@ func Register(indicator Indicator) {
 	defaultHandler.indicators = append(defaultHandler.indicators, indicator)
 }
 
+func SetComponentNum(num int) {
+	defaultHandler.indicatorNum = num
+}
+
 func UnRegister(role string) {
 	defaultHandler.unregisterLock.Lock()
 	defer defaultHandler.unregisterLock.Unlock()
@@ -86,11 +91,13 @@ func (handler *HealthHandler) ServeHTTP(w http.ResponseWriter, r *http.Request)
 		State: "OK",
 	}
 	ctx := context.Background()
+	healthNum := 0
 	for _, in := range handler.indicators {
 		handler.unregisterLock.RLock()
 		_, unregistered := handler.unregisteredRoles[in.GetName()]
 		handler.unregisterLock.RUnlock()
 		if unregistered {
+			healthNum++
 			continue
 		}
 		code := in.Health(ctx)
@@ -98,11 +105,15 @@ func (handler *HealthHandler) ServeHTTP(w http.ResponseWriter, r *http.Request)
 			Name: in.GetName(),
 			Code: code,
 		})
-		if code != commonpb.StateCode_Healthy && code != commonpb.StateCode_StandBy {
-			resp.State = fmt.Sprintf("component %s state is %s", in.GetName(), code.String())
+		if code == commonpb.StateCode_Healthy || code == commonpb.StateCode_StandBy {
+			healthNum++
 		}
 	}
 
+	if healthNum != handler.indicatorNum {
+		resp.State = fmt.Sprintf("Not all components are healthy, %d/%d", healthNum, handler.indicatorNum)
+	}
+
 	if resp.State == "OK" {
 		w.WriteHeader(http.StatusOK)
 	} else {

internal/http/server_test.go

@@ -101,6 +101,7 @@ func (suite *HTTPServerTestSuite) TestHealthzHandler() {
 	url := "http://localhost:" + DefaultListenPort + "/healthz"
 	client := http.Client{}
 
+	healthz.SetComponentNum(1)
 	healthz.Register(&MockIndicator{"m1", commonpb.StateCode_Healthy})
 
 	req, _ := http.NewRequest(http.MethodGet, url, nil)
@@ -118,6 +119,7 @@ func (suite *HTTPServerTestSuite) TestHealthzHandler() {
 	body, _ = io.ReadAll(resp.Body)
 	suite.Equal("{\"state\":\"OK\",\"detail\":[{\"name\":\"m1\",\"code\":1}]}", string(body))
 
+	healthz.SetComponentNum(2)
 	healthz.Register(&MockIndicator{"m2", commonpb.StateCode_Abnormal})
 	req, _ = http.NewRequest(http.MethodGet, url, nil)
 	req.Header.Set("Content-Type", "application/json")
@@ -125,7 +127,10 @@ func (suite *HTTPServerTestSuite) TestHealthzHandler() {
 	suite.Nil(err)
 	defer resp.Body.Close()
 	body, _ = io.ReadAll(resp.Body)
-	suite.Equal("{\"state\":\"component m2 state is Abnormal\",\"detail\":[{\"name\":\"m1\",\"code\":1},{\"name\":\"m2\",\"code\":2}]}", string(body))
+	respObj := &healthz.HealthResponse{}
+	err = json.Unmarshal(body, respObj)
+	suite.NoError(err)
+	suite.NotEqual("OK", respObj.State)
 }
 
 func (suite *HTTPServerTestSuite) TestEventlogHandler() {