Add disabled and prometheus metric providers

FAB-12694 #done

Change-Id: I60a243b6f5376f8d24f6856f01dd40e3e053404c
Signed-off-by: Matthew Sykes <sykesmat@us.ibm.com>

common/metrics/disabled/disabled_suite_test.go

@@ -0,0 +1,19 @@
+/*
+Copyright IBM Corp. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package disabled_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+func TestDisabled(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Disabled Suite")
+}

common/metrics/disabled/provider.go

@@ -0,0 +1,39 @@
+/*
+Copyright IBM Corp. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package disabled
+
+import (
+	"github.com/hyperledger/fabric/common/metrics"
+)
+
+type Provider struct{}
+
+func (p *Provider) NewCounter(o metrics.CounterOpts) metrics.Counter       { return &Counter{} }
+func (p *Provider) NewGauge(o metrics.GaugeOpts) metrics.Gauge             { return &Gauge{} }
+func (p *Provider) NewHistogram(o metrics.HistogramOpts) metrics.Histogram { return &Histogram{} }
+
+type Counter struct{}
+
+func (c *Counter) Add(delta float64) {}
+func (c *Counter) With(labelValues ...string) metrics.Counter {
+	return c
+}
+
+type Gauge struct{}
+
+func (g *Gauge) Add(delta float64) {}
+func (g *Gauge) Set(delta float64) {}
+func (g *Gauge) With(labelValues ...string) metrics.Gauge {
+	return g
+}
+
+type Histogram struct{}
+
+func (h *Histogram) Observe(value float64) {}
+func (h *Histogram) With(labelValues ...string) metrics.Histogram {
+	return h
+}

common/metrics/disabled/provider_test.go

@@ -0,0 +1,54 @@
+/*
+Copyright IBM Corp. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package disabled_test
+
+import (
+	"github.com/hyperledger/fabric/common/metrics"
+	"github.com/hyperledger/fabric/common/metrics/disabled"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Provider", func() {
+	var p metrics.Provider
+
+	BeforeEach(func() {
+		p = &disabled.Provider{}
+	})
+
+	Describe("NewCounter", func() {
+		It("creates a no-op counter that doesn't blow up", func() {
+			c := p.NewCounter(metrics.CounterOpts{})
+			Expect(c).NotTo(BeNil())
+
+			c.Add(1)
+			c.With("whatever").Add(2)
+		})
+	})
+
+	Describe("NewGauge", func() {
+		It("creates a no-op gauge that doesn't blow up", func() {
+			g := p.NewGauge(metrics.GaugeOpts{})
+			Expect(g).NotTo(BeNil())
+
+			g.Set(1)
+			g.Add(1)
+			g.With("whatever").Set(2)
+			g.With("whatever").Add(2)
+		})
+	})
+
+	Describe("NewHistogram", func() {
+		It("creates a no-op histogram that doesn't blow up", func() {
+			h := p.NewHistogram(metrics.HistogramOpts{})
+			Expect(h).NotTo(BeNil())
+
+			h.Observe(1)
+			h.With("whatever").Observe(2)
+		})
+	})
+})

common/metrics/prometheus/prometheus_suite_test.go

@@ -0,0 +1,19 @@
+/*
+Copyright IBM Corp. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package prometheus_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+func TestPrometheus(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Prometheus Suite")
+}

common/metrics/prometheus/provider.go

@@ -0,0 +1,77 @@
+/*
+Copyright IBM Corp. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package prometheus
+
+import (
+	kitmetrics "github.com/go-kit/kit/metrics"
+	"github.com/go-kit/kit/metrics/prometheus"
+	"github.com/hyperledger/fabric/common/metrics"
+	prom "github.com/prometheus/client_golang/prometheus"
+)
+
+type Provider struct{}
+
+func (p *Provider) NewCounter(o metrics.CounterOpts) metrics.Counter {
+	return &Counter{
+		Counter: prometheus.NewCounterFrom(
+			prom.CounterOpts{
+				Namespace: o.Namespace,
+				Subsystem: o.Subsystem,
+				Name:      o.Name,
+				Help:      o.Help,
+			},
+			o.LabelNames,
+		),
+	}
+}
+
+func (p *Provider) NewGauge(o metrics.GaugeOpts) metrics.Gauge {
+	return &Gauge{
+		Gauge: prometheus.NewGaugeFrom(
+			prom.GaugeOpts{
+				Namespace: o.Namespace,
+				Subsystem: o.Subsystem,
+				Name:      o.Name,
+				Help:      o.Help,
+			},
+			o.LabelNames,
+		),
+	}
+}
+
+func (p *Provider) NewHistogram(o metrics.HistogramOpts) metrics.Histogram {
+	return &Histogram{
+		Histogram: prometheus.NewHistogramFrom(
+			prom.HistogramOpts{
+				Namespace: o.Namespace,
+				Subsystem: o.Subsystem,
+				Name:      o.Name,
+				Help:      o.Help,
+				Buckets:   o.Buckets,
+			},
+			o.LabelNames,
+		),
+	}
+}
+
+type Counter struct{ kitmetrics.Counter }
+
+func (c *Counter) With(labelValues ...string) metrics.Counter {
+	return &Counter{Counter: c.Counter.With(labelValues...)}
+}
+
+type Gauge struct{ kitmetrics.Gauge }
+
+func (g *Gauge) With(labelValues ...string) metrics.Gauge {
+	return &Gauge{Gauge: g.Gauge.With(labelValues...)}
+}
+
+type Histogram struct{ kitmetrics.Histogram }
+
+func (h *Histogram) With(labelValues ...string) metrics.Histogram {
+	return &Histogram{Histogram: h.Histogram.With(labelValues...)}
+}