feat(metrics): let servers outside net/http record user metrics

Commit `f7a24d3`

Antonio Mika · 2026-10-25 21:57:09 -0400 EDT

parent 8d599bd

feat(metrics): let servers outside net/http record user metrics

2 files changed, +29, -5

M pkg/shared/router/metrics.go

M pkg/shared/router/metrics_test.go

M pkg/shared/router/metrics.go

+11, -5

......@@ -88,14 +88,20 @@ func (m *UserMetrics) Handler(next http.Handler) http.Handler {
		next.ServeHTTP(mw, r.WithContext(context.WithValue(r.Context(), ctxUserKey{}, &user)))

		status := mw.Status()
		user = m.resolveUser(r, user, status)
		labels := []string{user, strconv.Itoa(status), metricMethod(r.Method)}
		m.requests.WithLabelValues(labels...).Inc()
		m.duration.WithLabelValues(labels...).Observe(time.Since(start).Seconds())
		m.bytes.WithLabelValues(user).Add(float64(mw.bytes))
		m.Observe(m.resolveUser(r, user, status), status, r.Method, time.Since(start), mw.bytes)
	})
}

// Observe records one request for servers that can't use Handler, such as
// tuns's gin logger. user must already be confirmed to exist. A negative
// size, which gin reports when nothing was written, counts as zero bytes.
func (m *UserMetrics) Observe(user string, status int, method string, elapsed time.Duration, bytes int64) {
	labels := []string{user, strconv.Itoa(status), metricMethod(method)}
	m.requests.WithLabelValues(labels...).Inc()
	m.duration.WithLabelValues(labels...).Observe(elapsed.Seconds())
	m.bytes.WithLabelValues(user).Add(float64(max(bytes, 0)))
}

func (m *UserMetrics) resolveUser(r *http.Request, user string, status int) string {
	if user != "" {
		m.known.Add(user, struct{}{})

M pkg/shared/router/metrics_test.go

+18, -0

......@@ -129,6 +129,24 @@ func TestUserMetricsMethod(t *testing.T) {
	}
}

func TestUserMetricsObserve(t *testing.T) {
	reg := prometheus.NewRegistry()
	m := NewUserMetrics("test", reg, UserMetricsOpts{})

	m.Observe("carol", http.StatusOK, http.MethodGet, 0, 7)
	m.Observe("carol", http.StatusNotModified, "MADEUP", 0, -1)

	if got := metricValue(t, reg, "pico_http_requests_total", map[string]string{"user": "carol", "status": "200", "method": "GET"}); got != 1 {
		t.Errorf("200 requests = %v, want 1", got)
	}
	if got := metricValue(t, reg, "pico_http_requests_total", map[string]string{"user": "carol", "status": "304", "method": "OTHER"}); got != 1 {
		t.Errorf("304 requests = %v, want 1", got)
	}
	if got := metricValue(t, reg, "pico_http_response_bytes_total", map[string]string{"user": "carol"}); got != 7 {
		t.Errorf("bytes = %v, want 7", got)
	}
}

func TestUserMetricsHijack(t *testing.T) {
	reg := prometheus.NewRegistry()
	h := NewUserMetrics("test", reg, UserMetricsOpts{}).Handler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

...	...		@@ -88,14 +88,20 @@ func (m *UserMetrics) Handler(next http.Handler) http.Handler {
88	88		next.ServeHTTP(mw, r.WithContext(context.WithValue(r.Context(), ctxUserKey{}, &user)))
89	89
90	90		status := mw.Status()
91		-	user = m.resolveUser(r, user, status)
92		-	labels := []string{user, strconv.Itoa(status), metricMethod(r.Method)}
93		-	m.requests.WithLabelValues(labels...).Inc()
94		-	m.duration.WithLabelValues(labels...).Observe(time.Since(start).Seconds())
95		-	m.bytes.WithLabelValues(user).Add(float64(mw.bytes))
	91	+	m.Observe(m.resolveUser(r, user, status), status, r.Method, time.Since(start), mw.bytes)
96	92		})
97	93		}
98	94
	95	+	// Observe records one request for servers that can't use Handler, such as
	96	+	// tuns's gin logger. user must already be confirmed to exist. A negative
	97	+	// size, which gin reports when nothing was written, counts as zero bytes.
	98	+	func (m *UserMetrics) Observe(user string, status int, method string, elapsed time.Duration, bytes int64) {
	99	+	labels := []string{user, strconv.Itoa(status), metricMethod(method)}
	100	+	m.requests.WithLabelValues(labels...).Inc()
	101	+	m.duration.WithLabelValues(labels...).Observe(elapsed.Seconds())
	102	+	m.bytes.WithLabelValues(user).Add(float64(max(bytes, 0)))
	103	+	}
	104	+
99	105		func (m UserMetrics) resolveUser(r http.Request, user string, status int) string {
100	106		if user != "" {
101	107		m.known.Add(user, struct{}{})

...	...		@@ -129,6 +129,24 @@ func TestUserMetricsMethod(t *testing.T) {
129	129		}
130	130		}
131	131
	132	+	func TestUserMetricsObserve(t *testing.T) {
	133	+	reg := prometheus.NewRegistry()
	134	+	m := NewUserMetrics("test", reg, UserMetricsOpts{})
	135	+
	136	+	m.Observe("carol", http.StatusOK, http.MethodGet, 0, 7)
	137	+	m.Observe("carol", http.StatusNotModified, "MADEUP", 0, -1)
	138	+
	139	+	if got := metricValue(t, reg, "pico_http_requests_total", map[string]string{"user": "carol", "status": "200", "method": "GET"}); got != 1 {
	140	+	t.Errorf("200 requests = %v, want 1", got)
	141	+	}
	142	+	if got := metricValue(t, reg, "pico_http_requests_total", map[string]string{"user": "carol", "status": "304", "method": "OTHER"}); got != 1 {
	143	+	t.Errorf("304 requests = %v, want 1", got)
	144	+	}
	145	+	if got := metricValue(t, reg, "pico_http_response_bytes_total", map[string]string{"user": "carol"}); got != 7 {
	146	+	t.Errorf("bytes = %v, want 7", got)
	147	+	}
	148	+	}
	149	+
132	150		func TestUserMetricsHijack(t *testing.T) {
133	151		reg := prometheus.NewRegistry()
134	152		h := NewUserMetrics("test", reg, UserMetricsOpts{}).Handler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

Commit f7a24d3

Commit `f7a24d3`