chore: simplify prometheus check (#3672)

core/metric/counter.go

@@ -3,7 +3,6 @@ package metric
 import (
 	prom "github.com/prometheus/client_golang/prometheus"
 	"github.com/zeromicro/go-zero/core/proc"
-	"github.com/zeromicro/go-zero/core/prometheus"
 )
 
 type (
@@ -47,20 +46,16 @@ func NewCounterVec(cfg *CounterVecOpts) CounterVec {
 	return cv
 }
 
-func (cv *promCounterVec) Inc(labels ...string) {
-	if !prometheus.Enabled() {
-		return
-	}
-
-	cv.counter.WithLabelValues(labels...).Inc()
-}
-
 func (cv *promCounterVec) Add(v float64, labels ...string) {
-	if !prometheus.Enabled() {
-		return
+	update(func() {
+		cv.counter.WithLabelValues(labels...).Add(v)
+	})
 }
 
-	cv.counter.WithLabelValues(labels...).Add(v)
+func (cv *promCounterVec) Inc(labels ...string) {
+	update(func() {
+		cv.counter.WithLabelValues(labels...).Inc()
+	})
 }
 
 func (cv *promCounterVec) close() bool {

core/metric/gauge.go

@@ -3,7 +3,6 @@ package metric
 import (
 	prom "github.com/prometheus/client_golang/prometheus"
 	"github.com/zeromicro/go-zero/core/proc"
-	"github.com/zeromicro/go-zero/core/prometheus"
 )
 
 type (
@@ -36,8 +35,7 @@ func NewGaugeVec(cfg *GaugeVecOpts) GaugeVec {
 		return nil
 	}
 
-	vec := prom.NewGaugeVec(
-		prom.GaugeOpts{
+	vec := prom.NewGaugeVec(prom.GaugeOpts{
 		Namespace: cfg.Namespace,
 		Subsystem: cfg.Subsystem,
 		Name:      cfg.Name,
@@ -54,42 +52,34 @@ func NewGaugeVec(cfg *GaugeVecOpts) GaugeVec {
 	return gv
 }
 
-func (gv *promGaugeVec) Set(v float64, labels ...string) {
-	if !prometheus.Enabled() {
-		return
-	}
-
-	gv.gauge.WithLabelValues(labels...).Set(v)
-}
-
-func (gv *promGaugeVec) Inc(labels ...string) {
-	if !prometheus.Enabled() {
-		return
-	}
-
-	gv.gauge.WithLabelValues(labels...).Inc()
+func (gv *promGaugeVec) Add(v float64, labels ...string) {
+	update(func() {
+		gv.gauge.WithLabelValues(labels...).Add(v)
+	})
 }
 
 func (gv *promGaugeVec) Dec(labels ...string) {
-	if !prometheus.Enabled() {
-		return
-	}
+	update(func() {
 		gv.gauge.WithLabelValues(labels...).Dec()
+	})
 }
 
-func (gv *promGaugeVec) Add(v float64, labels ...string) {
-	if !prometheus.Enabled() {
-		return
+func (gv *promGaugeVec) Inc(labels ...string) {
+	update(func() {
+		gv.gauge.WithLabelValues(labels...).Inc()
+	})
 }
 
-	gv.gauge.WithLabelValues(labels...).Add(v)
+func (gv *promGaugeVec) Set(v float64, labels ...string) {
+	update(func() {
+		gv.gauge.WithLabelValues(labels...).Set(v)
+	})
 }
 
 func (gv *promGaugeVec) Sub(v float64, labels ...string) {
-	if !prometheus.Enabled() {
-		return
-	}
+	update(func() {
 		gv.gauge.WithLabelValues(labels...).Sub(v)
+	})
 }
 
 func (gv *promGaugeVec) close() bool {

core/metric/histogram.go

@@ -3,7 +3,6 @@ package metric
 import (
 	prom "github.com/prometheus/client_golang/prometheus"
 	"github.com/zeromicro/go-zero/core/proc"
-	"github.com/zeromicro/go-zero/core/prometheus"
 )
 
 type (
@@ -54,11 +53,9 @@ func NewHistogramVec(cfg *HistogramVecOpts) HistogramVec {
 }
 
 func (hv *promHistogramVec) Observe(v int64, labels ...string) {
-	if !prometheus.Enabled() {
-		return
-	}
-
+	update(func() {
 		hv.histogram.WithLabelValues(labels...).Observe(float64(v))
+	})
 }
 
 func (hv *promHistogramVec) close() bool {

core/metric/metric.go

@@ -1,5 +1,7 @@
 package metric
 
+import "github.com/zeromicro/go-zero/core/prometheus"
+
 // A VectorOpts is a general configuration.
 type VectorOpts struct {
 	Namespace string
@@ -8,3 +10,11 @@ type VectorOpts struct {
 	Help      string
 	Labels    []string
 }
+
+func update(fn func()) {
+	if !prometheus.Enabled() {
+		return
+	}
+
+	fn()
+}

core/metric/summary.go

@@ -3,7 +3,6 @@ package metric
 import (
 	prom "github.com/prometheus/client_golang/prometheus"
 	"github.com/zeromicro/go-zero/core/proc"
-	"github.com/zeromicro/go-zero/core/prometheus"
 )
 
 type (
@@ -53,11 +52,9 @@ func NewSummaryVec(cfg *SummaryVecOpts) SummaryVec {
 }
 
 func (sv *promSummaryVec) Observe(v float64, labels ...string) {
-	if !prometheus.Enabled() {
-		return
-	}
-
+	update(func() {
 		sv.summary.WithLabelValues(labels...).Observe(v)
+	})
 }
 
 func (sv *promSummaryVec) close() bool {