test(contrib): add unit test for contrib/metrics/prometheus (#2182)

Co-authored-by: rogerogers <rogers@rogerogers.com>

contrib/metrics/prometheus/counter_test.go

@@ -0,0 +1,65 @@
+package prometheus
+
+import (
+	"bytes"
+	"fmt"
+	"testing"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/common/expfmt"
+)
+
+func gatherLatest(reg *prometheus.Registry) (result string, err error) {
+	mfs, err := reg.Gather()
+	if err != nil {
+		return "", err
+	}
+	buf := &bytes.Buffer{}
+
+	enc := expfmt.NewEncoder(buf, expfmt.FmtText)
+	for _, mf := range mfs {
+		if err = enc.Encode(mf); err != nil {
+			return "", err
+		}
+	}
+	return buf.String(), nil
+}
+
+func TestCounter(t *testing.T) {
+	expect := `# HELP test_request_test_metric test
+# TYPE test_request_test_metric counter
+test_request_test_metric{code="test",kind="test",operation="test",reason="test"} %d
+`
+
+	counterVec := prometheus.NewCounterVec(prometheus.CounterOpts{
+		Namespace: "test",
+		Name:      "test_metric",
+		Subsystem: "request",
+		Help:      "test",
+	}, []string{"kind", "operation", "code", "reason"})
+
+	counter := NewCounter(counterVec)
+	counter.With("test", "test", "test", "test").Inc()
+
+	reg := prometheus.NewRegistry()
+	reg.MustRegister(counterVec)
+
+	result, err := gatherLatest(reg)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if result != fmt.Sprintf(expect, 1) {
+		t.Fatal("metrics error")
+	}
+
+	counter.With("test", "test", "test", "test").Add(10)
+	result, err = gatherLatest(reg)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if result != fmt.Sprintf(expect, 11) {
+		t.Fatal("metrics error")
+	}
+}

contrib/metrics/prometheus/gauge_test.go

@@ -0,0 +1,55 @@
+package prometheus
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func TestGuage(t *testing.T) {
+	expect := `# HELP test_request_test_guage_metric test
+# TYPE test_request_test_guage_metric gauge
+test_request_test_guage_metric{code="test",kind="test",operation="test",reason="test"} %d
+`
+
+	guageVec := prometheus.NewGaugeVec(prometheus.GaugeOpts{
+		Namespace: "test",
+		Name:      "test_guage_metric",
+		Subsystem: "request",
+		Help:      "test",
+	}, []string{"kind", "operation", "code", "reason"})
+
+	guage := NewGauge(guageVec)
+	guage.With("test", "test", "test", "test").Set(1)
+
+	reg := prometheus.NewRegistry()
+	reg.MustRegister(guageVec)
+
+	result, err := gatherLatest(reg)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if result != fmt.Sprintf(expect, 1) {
+		t.Fatal("metrics error")
+	}
+
+	guage.With("test", "test", "test", "test").Add(1)
+	result, err = gatherLatest(reg)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if result != fmt.Sprintf(expect, 2) {
+		t.Fatal("metrics error")
+	}
+
+	guage.With("test", "test", "test", "test").Sub(1)
+	result, err = gatherLatest(reg)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if result != fmt.Sprintf(expect, 1) {
+		t.Fatal("metrics error")
+	}
+}

contrib/metrics/prometheus/go.mod

@@ -5,6 +5,7 @@ go 1.16
 require (
 	github.com/go-kratos/kratos/v2 v2.3.1
 	github.com/prometheus/client_golang v1.12.2
+	github.com/prometheus/common v0.32.1
 )
 
 replace github.com/go-kratos/kratos/v2 => ../../../

contrib/metrics/prometheus/histogram_test.go

@@ -0,0 +1,77 @@
+package prometheus
+
+import (
+	"fmt"
+	"strconv"
+	"testing"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func intToFloatString(in int) string {
+	return strconv.FormatFloat(float64(in), 'f', -1, 64)
+}
+
+func TestHistogram(t *testing.T) {
+	expect := `# HELP test_request_test_metrics test
+# TYPE test_request_test_metrics histogram
+test_request_test_metrics_bucket{code="test",kind="test",operation="test",reason="test",le="0.05"} %s
+test_request_test_metrics_bucket{code="test",kind="test",operation="test",reason="test",le="0.1"} %s
+test_request_test_metrics_bucket{code="test",kind="test",operation="test",reason="test",le="0.25"} %s
+test_request_test_metrics_bucket{code="test",kind="test",operation="test",reason="test",le="0.5"} %s
+test_request_test_metrics_bucket{code="test",kind="test",operation="test",reason="test",le="1"} %s
+test_request_test_metrics_bucket{code="test",kind="test",operation="test",reason="test",le="+Inf"} %s
+test_request_test_metrics_sum{code="test",kind="test",operation="test",reason="test"} %s
+test_request_test_metrics_count{code="test",kind="test",operation="test",reason="test"} %s
+`
+
+	histogramVec := prometheus.NewHistogramVec(prometheus.HistogramOpts{
+		Namespace: "test",
+		Name:      "test_metrics",
+		Subsystem: "request",
+		Help:      "test",
+		Buckets:   []float64{0.05, 0.1, 0.250, 0.5, 1},
+	}, []string{"kind", "operation", "code", "reason"})
+
+	histogram := NewHistogram(histogramVec)
+	histogram.With("test", "test", "test", "test").Observe(0.5)
+
+	reg := prometheus.NewRegistry()
+	reg.MustRegister(histogramVec)
+
+	result, err := gatherLatest(reg)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if result != fmt.Sprintf(expect,
+		intToFloatString(0),
+		intToFloatString(0),
+		intToFloatString(0),
+		intToFloatString(1),
+		intToFloatString(1),
+		intToFloatString(1),
+		"0.5",
+		intToFloatString(1)) {
+		t.Fatal("metrics error")
+	}
+
+	histogram.With("test", "test", "test", "test").Observe(0.1)
+	result, err = gatherLatest(reg)
+
+	if err != nil {
+		t.Fatal(err)
+	}
+	if result != fmt.Sprintf(expect,
+		intToFloatString(0),
+		intToFloatString(1),
+		intToFloatString(1),
+		intToFloatString(2),
+		intToFloatString(2),
+		intToFloatString(2),
+		"0.6",
+		intToFloatString(2),
+	) {
+		t.Fatal("metrics error")
+	}
+}

contrib/metrics/prometheus/summary_test.go

@@ -0,0 +1,47 @@
+package prometheus
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func TestSummary(t *testing.T) {
+	expect := `# HELP test_request_test_metric test
+# TYPE test_request_test_metric summary
+test_request_test_metric_sum{code="test",kind="test",operation="test",reason="test"} %s
+test_request_test_metric_count{code="test",kind="test",operation="test",reason="test"} %s
+`
+
+	summaryVec := prometheus.NewSummaryVec(prometheus.SummaryOpts{
+		Namespace: "test",
+		Name:      "test_metric",
+		Subsystem: "request",
+		Help:      "test",
+	}, []string{"kind", "operation", "code", "reason"})
+
+	summary := NewSummary(summaryVec)
+	summary.With("test", "test", "test", "test").Observe(1)
+
+	reg := prometheus.NewRegistry()
+	reg.MustRegister(summaryVec)
+	result, err := gatherLatest(reg)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if result != fmt.Sprintf(expect, intToFloatString(1), intToFloatString(1)) {
+		t.Fatal("metrics error")
+	}
+	summary.With("test", "test", "test", "test").Observe(10)
+
+	result, err = gatherLatest(reg)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if result != fmt.Sprintf(expect, intToFloatString(11), intToFloatString(2)) {
+		t.Fatal("metrics error")
+	}
+}