add method to reset sender metrics (#238)

Author: karenychen

v2/metrics/sender/types.go

@@ -51,6 +51,7 @@ type Recorder interface {
 	Init(registerer prom.Registerer)
 	IncSendMessageSuccessCount()
 	IncSendMessageFailureCount()
+	ResetSendMessageCount()
 	IncHealthCheckSuccessCount(namespace, entity string)
 	IncHealthCheckFailureCount(namespace, entity string)
 }
@@ -71,6 +72,10 @@ func (m *Registry) IncSendMessageFailureCount() {
 		}).Inc()
 }
 
+func (m *Registry) ResetSendMessageCount() {
+	m.MessageSentCount.Reset()
+}
+
 // IncHealthCheckSuccessCount increases the connection success gauge and resets the failure gauge
 func (m *Registry) IncHealthCheckSuccessCount(namespace, entity string) {
 	m.HealthCheckCount.With(

v2/metrics/sender/types_test.go

@@ -61,6 +61,12 @@ func TestSendMetrics(t *testing.T) {
 	count, err = informer.GetSendMessageFailureCount()
 	g.Expect(err).ToNot(HaveOccurred())
 	g.Expect(count).To(Equal(float64(1)))
+
+	// count resets properly
+	r.ResetSendMessageCount()
+	count, err = informer.GetSendMessageFailureCount()
+	g.Expect(err).ToNot(HaveOccurred())
+	g.Expect(count).To(Equal(float64(0)))
 }
 
 func TestConnectionMetrics(t *testing.T) {