add prometheus

api.go

@@ -13,7 +13,7 @@ import (
 var (
 	validate              = validator.New()
 	requestLogidGetter    = defaultLogidGetter
-	handlerMapper         = map[string]Handler{}
+	requestHandlerMapper  = map[string]Handler{}
 	errCodeUnknownError   = -10000
 	errCodeParameterError = -20000
 	errCodeUnimplementApi = -20401
@@ -47,7 +47,9 @@ func NewEngine() *Engine {
 
 func (e *Engine) POST(uri string, handler Handler) {
 	h := handlerWrapper(handler.HandlerFunc())
-	handlerMapper[fmt.Sprintf("%v", h)] = handler
+	hkey := fmt.Sprintf("%v", h)
+	requestHandlerMapper[hkey] = handler
+	log.Infof("api handler [%s] registor success", hkey)
 	e.Engine.POST(uri, h)
 }
 

context.go

@@ -26,6 +26,7 @@ type Context struct {
 	httpstatus  int
 	starttime   time.Time
 	output      interface{}
+	errcode     int
 }
 
 func New(c *gin.Context) *Context {
@@ -146,28 +147,62 @@ func (c *Context) RESULT(output interface{}) error {
 		cost := time.Now().Sub(c.starttime).Milliseconds()
 		noticeStr := fmt.Sprintf("cost: %dms, output: '%s'", cost, string(b))
 		log.NoticefWithDepth(calldepth, noticeStr)
+
+		//// metric ////////////////////////////////////////
+		c.recordMetric()
 	}(&output)
 
-	if _, ok := t.FieldByName("ErrCode"); !ok {
-		errstr := "Result MUST have 'ErrCode' field"
-		output = BaseWithErrCodeOutput{errCodeUnknownError, errstr}
-		c.ShapeOutput(output)
-		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.shapeOutput(output)
+		c.errcode = reflect.ValueOf(output).FieldByName("ErrCode").GetInt()
 		c.IndentedJSON(c.httpstatus, output)
 		return errors.New(errstr)
 	}
-	c.ShapeOutput(output)
+	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.IndentedJSON(c.httpstatus, output)
+		return errors.New(errstr)
+	}
+
+	c.shapeOutput(output)
+	c.errcode = reflect.ValueOf(output).FieldByName("ErrCode").GetInt()
 	c.IndentedJSON(c.httpstatus, output)
 	return nil
 }
 
-func (c *Context) ShapeOutput(o interface{}) {
+func (c *Context) RESULT_ERROR(eno int, err string) error {
+	if c.resultentry == "" {
+		c.resultentry = "RESULT_ERROR"
+	}
+
+	result := BaseWithErrCodeOutput{eno, err}
+	c.errcode = eno
+	return c.RESULT(result)
+}
+
+func (c *Context) RESULT_PARAMETER_ERROR(err string) error {
+	if c.resultentry == "" {
+		c.resultentry = "RESULT_PARAMETER_ERROR"
+	}
+	return c.RESULT_ERROR(errCodeParameterError, err)
+}
+
+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
+}
+
+func (c *Context) shapeOutput(o interface{}) {
 	if c.output == nil {
 		return
 	}
@@ -183,26 +218,23 @@ func (c *Context) ShapeOutput(o interface{}) {
 	return
 }
 
-func (c *Context) ApiHandler() Handler {
-	h := c.Context.Handler()
-	if handler, ok := handlerMapper[fmt.Sprintf("%v", h)]; ok {
-		return handler
+func (c *Context) recordMetric() {
+	if metricApiCounter == nil ||
+		metricApiSummary == nil {
+		return
 	}
-	return nil
-}
+	var (
+		h       = c.ApiHandler()
+		api     = h.Name()
+		cost    = time.Now().Sub(c.starttime).Milliseconds()
+		appid   = c.AppId
+		errcode = c.errcode
+		counter = metricApiCounter.WithLabelValues(api, errcode, appid)
+		summary = metricApiSummary.WithLabelValues(api, errcode, appid)
+	)
 
-func (c *Context) RESULT_ERROR(eno int, err string) error {
-	if c.resultentry == "" {
-		c.resultentry = "RESULT_ERROR"
-	}
-
-	result := BaseWithErrCodeOutput{eno, err}
-	return c.RESULT(result)
-}
-
-func (c *Context) RESULT_PARAMETER_ERROR(err string) error {
-	if c.resultentry == "" {
-		c.resultentry = "RESULT_PARAMETER_ERROR"
-	}
-	return c.RESULT_ERROR(errCodeParameterError, err)
+	// Metric 1. api request counter
+	counter.Inc()
+	// Metric 2. api request cost/latency
+	summary.Observe(cost)
 }

prometheus.go

@@ -0,0 +1,79 @@
+package api
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+	"github.com/prometheus/client_golang/prometheus/push"
+)
+
+var (
+	MetricExporterPusher                         = func() {}
+	MetricExporterHandler Handler                = nil
+	metricRegistry        *prometheus.Registry   = nil
+	metricApiCounter      *prometheus.CounterVec = nil
+	metricApiSummary      *prometheus.SummaryVec = nil
+)
+
+type metricExporterHandler struct {
+	name            string
+	promhttpHandler http.Handler
+}
+
+func (m *metricExporterHandler) Name() string {
+	return m.apiName
+}
+
+func (m *metricExporterHandler) HandlerFunc() HandlerFunc {
+	return func(c *Context) (err error) {
+		m.promhttpHandler.ServeHTTP(c.ResponseWriter, c.Request)
+		return nil
+	}
+}
+
+func InitMetrics() {
+	metricApiCounter = prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "api_requests_total",
+			Help: "How many HTTP requests processed",
+		},
+		[]string{"api", "errcode", "appid"},
+	)
+	metricApiSummary = prometheus.NewSummaryVec(
+		prometheus.SummaryOpts{
+			Name:       "api_requests_summary",
+			Help:       "The api request summary of cost.",
+			Objectives: map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
+		},
+		[]string{"api", "errcode", "appid"},
+	)
+	metricRegistry = prometheus.NewRegistry()
+
+	opt := promhttp.HandlerOpts{Registry: metricRegistry}
+	metricRegistry.MustRegister(metricApiCounter)
+	metricRegistry.MustRegister(metricApiSummary)
+}
+
+func SetupMetricsExporterHandler(apiname string) {
+	if apiname == "" {
+		apiname = "premetheus_metrics_exporter"
+	}
+
+	MetricExporterHandler = &metricExporterHandler{
+		name:            apiname,
+		promhttpHandler: promhttp.HandlerFor(metricRegistry, opt),
+	}
+}
+
+func SetupMetricsExporterPusher(pushgateway string, jobname string) {
+	if jobname == "" {
+		jobname = fmt.Sprintf("api-metrics-job-%s", getExeFilename())
+	}
+
+	var pusher = push.New(pushgateway, jobname).Gatherer(metricRegistry)
+	MetricExporterPusher = func() {
+		pusher.Push()
+	}
+}

routes.go

@@ -34,6 +34,7 @@ package api
 // ///////////////////////////////////////////////////////////////////
 
 type Handler interface {
+	Name() string
 	HandlerFunc() HandlerFunc
 }
 type HandlerFunc func(*Context) error

util.go

@@ -0,0 +1,15 @@
+package api
+
+import (
+	"os"
+	"path/filepath"
+)
+
+// getExeFilename
+func getExeFilename() string {
+	_, logfilename := filepath.Split(os.Args[0])
+	if logfilename == "" {
+		panic("get exe filename failed")
+	}
+	return logfilename
+}