diff --git a/api.go b/api.go
index 5fc7872..b55ccf0 100644
--- a/api.go
+++ b/api.go
@@ -1,7 +1,6 @@
 package api
 
 import (
-	"fmt"
 	"reflect"
 
 	"github.com/gin-gonic/gin"
@@ -46,15 +45,40 @@ func NewEngine() *Engine {
 }
 
 func (e *Engine) POST(uri string, handler Handler) {
-	h := handlerWrapper(handler.HandlerFunc())
-	hkey := fmt.Sprintf("%v", h)
-	requestHandlerMapper[hkey] = handler
-	log.Infof("api handler [%s] registor success", hkey)
+	h := handlerWrapper(handler)
+	log.Infof("api handler [%v] registor success", handler)
 	e.Engine.POST(uri, h)
 }
 
 // handlerWrapper
-func handlerWrapper(handler HandlerFunc) gin.HandlerFunc {
+func handlerWrapper(handler Handler) gin.HandlerFunc {
+	handlerFunc := handler.HandlerFunc()
+	return func(c *gin.Context) {
+		// Case 1. get request handler
+		if c.Request == nil && c.Keys != nil {
+			c.Keys["handler"] = handler
+			return
+		}
+
+		// Case 2. normal case, user request will go this way
+		if icc, ok := c.Get("cc"); !ok {
+			log.Errorf("Unreachable Code: can not get cc(*api.Context) from *gin.Context")
+		} else if cc, ok := icc.(*Context); !ok {
+			log.Debugf("Unreachable Code: cc from *gin.Context is type of:[%s]", reflect.TypeOf(icc).String())
+			log.Errorf("Unreachable Code: cc from *gin.Context is not type of *api.Context")
+		} else {
+			// user request should go this way
+			defer cc.TryRecover()
+			cc.AppId = c.GetString("appid")
+			cc.UserId = c.GetUint64("userid")
+			handlerFunc(cc)
+			return
+		}
+	}
+}
+
+// handlerWrapper
+func handlerFuncWrapper(handler HandlerFunc) gin.HandlerFunc {
 	return func(c *gin.Context) {
 		if icc, ok := c.Get("cc"); !ok {
 			log.Errorf("Unreachable Code: can not get cc(*api.Context) from *gin.Context")
@@ -66,6 +90,7 @@ func handlerWrapper(handler HandlerFunc) gin.HandlerFunc {
 			cc.AppId = c.GetString("appid")
 			cc.UserId = c.GetUint64("userid")
 			handler(cc)
+			return
 		}
 	}
 }
@@ -113,8 +138,9 @@ func CC(c *gin.Context) *Context {
 }
 
 func ApiHandler(c *gin.Context) Handler {
-	cc := CC(c)
-	return cc.ApiHandler()
+	newc := &gin.Context{Request: nil, Keys: map[string]any{}}
+	c.Handler()(newc)
+	return newc.Keys["handler"].(Handler)
 }
 
 func DumpHandler(c *Context) error {
@@ -124,7 +150,7 @@ func DumpHandler(c *Context) error {
 }
 
 func ErrorHandler(c *gin.Context, errcode int, errmsg string) {
-	handler := handlerWrapper(func(c *Context) error {
+	handler := handlerFuncWrapper(func(c *Context) error {
 		return c.RESULT_ERROR(errcode, errmsg)
 	})
 	handler(c)
diff --git a/context.go b/context.go
index f14065c..ba46f20 100644
--- a/context.go
+++ b/context.go
@@ -7,6 +7,7 @@ import (
 	"net/http"
 	"reflect"
 	"runtime/debug"
+	"strconv"
 	"strings"
 	"time"
 
@@ -18,6 +19,7 @@ import (
 
 type Context struct {
 	*gin.Context
+	e *gin.Engine
 
 	AppId  string //current request appid, must not be empty
 	UserId uint64 //current request userid, maybe 0 if user unknown
@@ -152,25 +154,26 @@ func (c *Context) RESULT(output interface{}) error {
 		c.recordMetric()
 	}(&output)
 
-	if _, ok := t.FieldByName("ErrMsg"); !ok {
-		errstr := "Result MUST have 'ErrMsg' field"
-		output = BaseWithErrCodeOutput{errCodeUnknownError, errstr}
-		c.shapeOutput(output)
-		c.errcode = reflect.ValueOf(output).FieldByName("ErrCode").GetInt()
-		c.IndentedJSON(c.httpstatus, output)
-		return errors.New(errstr)
-	}
 	if _, ok := t.FieldByName("ErrCode"); !ok {
 		errstr := "Result MUST have 'ErrCode' field"
 		output = BaseWithErrCodeOutput{errCodeUnknownError, errstr}
 		c.shapeOutput(output)
-		c.errcode = reflect.ValueOf(output).FieldByName("ErrCode").GetInt()
+		c.errcode = int(reflect.ValueOf(output).FieldByName("ErrCode").Int())
+		c.IndentedJSON(c.httpstatus, output)
+		return errors.New(errstr)
+	}
+
+	if _, ok := t.FieldByName("ErrMsg"); !ok {
+		errstr := "Result MUST have 'ErrMsg' field"
+		output = BaseWithErrCodeOutput{errCodeUnknownError, errstr}
+		c.shapeOutput(output)
+		c.errcode = int(reflect.ValueOf(output).FieldByName("ErrCode").Int())
 		c.IndentedJSON(c.httpstatus, output)
 		return errors.New(errstr)
 	}
 
 	c.shapeOutput(output)
-	c.errcode = reflect.ValueOf(output).FieldByName("ErrCode").GetInt()
+	c.errcode = int(reflect.ValueOf(output).FieldByName("ErrCode").Int())
 	c.IndentedJSON(c.httpstatus, output)
 	return nil
 }
@@ -193,13 +196,7 @@ func (c *Context) RESULT_PARAMETER_ERROR(err string) error {
 }
 
 func (c *Context) ApiHandler() Handler {
-	h := c.Context.Handler()
-	hkey := fmt.Sprintf("%v", h)
-	if handler, ok := requestHandlerMapper[hkey]; ok {
-		return handler
-	}
-	log.Fatalf("api handler [%s] not found", hkey)
-	return nil
+	return ApiHandler(c.Context)
 }
 
 func (c *Context) shapeOutput(o interface{}) {
@@ -225,10 +222,11 @@ func (c *Context) recordMetric() {
 	}
 	var (
 		h       = c.ApiHandler()
-		api     = h.Name()
-		cost    = time.Now().Sub(c.starttime).Milliseconds()
+		api     = h.ApiName()
 		appid   = c.AppId
-		errcode = c.errcode
+		costus  = time.Now().Sub(c.starttime).Microseconds()
+		costms  = float64(costus) / 1000.0
+		errcode = strconv.Itoa(c.errcode)
 		counter = metricApiCounter.WithLabelValues(api, errcode, appid)
 		summary = metricApiSummary.WithLabelValues(api, errcode, appid)
 	)
@@ -236,5 +234,5 @@ func (c *Context) recordMetric() {
 	// Metric 1. api request counter
 	counter.Inc()
 	// Metric 2. api request cost/latency
-	summary.Observe(cost)
+	summary.Observe(costms)
 }
diff --git a/prometheus.go b/prometheus.go
index 5c7af3e..59ffc98 100644
--- a/prometheus.go
+++ b/prometheus.go
@@ -22,13 +22,13 @@ type metricExporterHandler struct {
 	promhttpHandler http.Handler
 }
 
-func (m *metricExporterHandler) Name() string {
-	return m.apiName
+func (m *metricExporterHandler) ApiName() string {
+	return m.name
 }
 
 func (m *metricExporterHandler) HandlerFunc() HandlerFunc {
 	return func(c *Context) (err error) {
-		m.promhttpHandler.ServeHTTP(c.ResponseWriter, c.Request)
+		m.promhttpHandler.ServeHTTP(c.Writer, c.Request)
 		return nil
 	}
 }
@@ -50,8 +50,6 @@ func InitMetrics() {
 		[]string{"api", "errcode", "appid"},
 	)
 	metricRegistry = prometheus.NewRegistry()
-
-	opt := promhttp.HandlerOpts{Registry: metricRegistry}
 	metricRegistry.MustRegister(metricApiCounter)
 	metricRegistry.MustRegister(metricApiSummary)
 }
@@ -61,6 +59,7 @@ func SetupMetricsExporterHandler(apiname string) {
 		apiname = "premetheus_metrics_exporter"
 	}
 
+	opt := promhttp.HandlerOpts{Registry: metricRegistry}
 	MetricExporterHandler = &metricExporterHandler{
 		name:            apiname,
 		promhttpHandler: promhttp.HandlerFor(metricRegistry, opt),
diff --git a/routes.go b/routes.go
index ce67880..90eb6fa 100644
--- a/routes.go
+++ b/routes.go
@@ -34,7 +34,7 @@ package api
 // ///////////////////////////////////////////////////////////////////
 
 type Handler interface {
-	Name() string
+	ApiName() string
 	HandlerFunc() HandlerFunc
 }
 type HandlerFunc func(*Context) error