feat: add metrics (#3624)

rest/httpc/internal/metricsinterceptor.go

@@ -0,0 +1,71 @@
+package internal
+
+import (
+	"net/http"
+	"net/url"
+	"strconv"
+	"time"
+
+	"github.com/zeromicro/go-zero/core/metric"
+	"github.com/zeromicro/go-zero/core/timex"
+)
+
+const clientNamespace = "httpc_client"
+
+var (
+	MetricClientReqDur = metric.NewHistogramVec(&metric.HistogramVecOpts{
+		Namespace: clientNamespace,
+		Subsystem: "requests",
+		Name:      "duration_ms",
+		Help:      "http client requests duration(ms).",
+		Labels:    []string{"name", "method", "url"},
+		Buckets:   []float64{0.25, 0.5, 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000, 2000, 5000, 10000, 15000},
+	})
+
+	MetricClientReqCodeTotal = metric.NewCounterVec(&metric.CounterVecOpts{
+		Namespace: clientNamespace,
+		Subsystem: "requests",
+		Name:      "code_total",
+		Help:      "http client requests code count.",
+		Labels:    []string{"name", "method", "url", "code"},
+	})
+)
+
+type (
+	MetricsURLRewriter func(u url.URL) string
+)
+
+func MetricsInterceptor(name string, pr MetricsURLRewriter) Interceptor {
+	return func(r *http.Request) (*http.Request, ResponseHandler) {
+		startTime := timex.Now()
+		return r, func(resp *http.Response, err error) {
+			u := cleanURL(*r.URL)
+			method := r.Method
+			var (
+				code int
+				path string
+			)
+			// error or resp is nil, set code=500
+			if err != nil || resp == nil {
+				code = http.StatusInternalServerError
+			} else {
+				code = resp.StatusCode
+			}
+			if pr != nil {
+				path = pr(u)
+			} else {
+				path = u.String()
+			}
+
+			MetricClientReqDur.ObserveFloat(float64(timex.Since(startTime))/float64(time.Millisecond), name, method, path)
+			MetricClientReqCodeTotal.Inc(name, method, path, strconv.Itoa(code))
+		}
+	}
+}
+
+func cleanURL(r url.URL) url.URL {
+	r.RawQuery = ""
+	r.RawFragment = ""
+	r.User = nil
+	return r
+}

rest/httpc/internal/metricsinterceptor_test.go

@@ -0,0 +1,35 @@
+package internal
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"github.com/golang/mock/gomock"
+	"github.com/stretchr/testify/assert"
+	"github.com/zeromicro/go-zero/core/logx"
+)
+
+func TestMetricsInterceptor(t *testing.T) {
+	c := gomock.NewController(t)
+	defer c.Finish()
+
+	logx.Disable()
+
+	svr := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		time.Sleep(100 * time.Millisecond)
+		w.WriteHeader(http.StatusInternalServerError)
+	}))
+	defer svr.Close()
+
+	req, err := http.NewRequest(http.MethodGet, svr.URL, nil)
+	assert.NotNil(t, req)
+	assert.Nil(t, err)
+	interceptor := MetricsInterceptor("test", nil)
+	req, handler := interceptor(req)
+	resp, err := http.DefaultClient.Do(req)
+	assert.NotNil(t, resp)
+	assert.Nil(t, err)
+	handler(resp, err)
+}