first commit

mw/prometheus/metrics.go

@@ -0,0 +1,93 @@
+package prometheus
+
+import (
+	"time"
+
+	metrics "github.com/prometheus/client_golang/prometheus"
+	"gitoa.ru/go-4devs/cache/mw"
+)
+
+const (
+	labelSet       = "label"
+	labelOperation = "operation"
+)
+
+//nolint: gochecknoglobals
+var (
+	hitCount = metrics.NewCounterVec(
+		metrics.CounterOpts{
+			Name: "cache_hit_total",
+			Help: "Counter of hits cache.",
+		},
+		[]string{labelSet},
+	)
+	missCount = metrics.NewCounterVec(
+		metrics.CounterOpts{
+			Name: "cache_miss_total",
+			Help: "Counter of misses cache.",
+		},
+		[]string{labelSet},
+	)
+	expiredCount = metrics.NewCounterVec(
+		metrics.CounterOpts{
+			Name: "cache_expired_total",
+			Help: "Counter of expired items in cache.",
+		},
+		[]string{labelSet},
+	)
+	errorsCount = metrics.NewCounterVec(
+		metrics.CounterOpts{
+			Name: "cache_errors_total",
+			Help: "Counter of errors in cache.",
+		},
+		[]string{labelSet, labelOperation},
+	)
+	responseTime = metrics.NewHistogramVec(
+		metrics.HistogramOpts{
+			Name: "cache_request_duration_seconds",
+			Help: "Histogram of RT for the request cache (seconds).",
+		},
+		[]string{labelSet, labelOperation},
+	)
+)
+
+//nolint: gochecknoinits
+func init() {
+	metrics.MustRegister(
+		hitCount,
+		missCount,
+		expiredCount,
+		errorsCount,
+		responseTime,
+	)
+}
+
+var _ mw.Metrics = Metrics{}
+
+// Metrics prometeus.
+type Metrics struct{}
+
+// Miss inc miss error cache.
+func (m Metrics) Miss(label string) {
+	missCount.WithLabelValues(label).Inc()
+}
+
+// Hit increment hit cache.
+func (m Metrics) Hit(label string) {
+	hitCount.WithLabelValues(label).Inc()
+}
+
+// Expired increment error expired.
+func (m Metrics) Expired(label string) {
+	expiredCount.WithLabelValues(label).Inc()
+}
+
+// Err increment base undefined error.
+func (m Metrics) Err(label string, operation string) {
+	errorsCount.WithLabelValues(label, operation).Inc()
+}
+
+// Observe time from start.
+func (m Metrics) Observe(label string, operation string, start time.Time) {
+	responseTime.WithLabelValues(label, operation).Observe(float64(time.Since(start)) / float64(time.Second))
+}