feat(probe): add target labels

Signed-off-by: Rory Z <[email protected]>

main_test.go

@@ -361,9 +361,14 @@ var _ = Describe("Check EMQX Exporter Probe", Label("probes"), func() {
 						WithTransform(func(m *dto.MetricFamily) dto.MetricType {
 							return m.GetType()
 						}, Equal(dto.MetricType_GAUGE)),
-						WithTransform(func(m *dto.MetricFamily) int {
-							return int(*m.Metric[0].Gauge.Value)
-						}, Equal(1)),
+						WithTransform(func(m *dto.MetricFamily) float64 {
+							return *m.GetMetric()[0].Gauge.Value
+						}, BeNumerically("==", 1)),
+						WithTransform(func(m *dto.MetricFamily) map[string]string {
+							return map[string]string{
+								m.GetMetric()[0].Label[0].GetName(): m.GetMetric()[0].Label[0].GetValue(),
+							}
+						}, HaveKeyWithValue("target", target)),
 					)),
 				))
 

prober/handler.go

@@ -38,12 +38,18 @@ func Handler(w http.ResponseWriter, r *http.Request, probes []config.Probe, logg
 		Subsystem: "mqtt",
 		Name:      "probe_success",
 		Help:      "Displays whether or not the probe was a success",
+		ConstLabels: prometheus.Labels{
+			"target": probe.Target,
+		},
 	})
 	probeDurationGauge := prometheus.NewGauge(prometheus.GaugeOpts{
 		Namespace: "emqx",
 		Subsystem: "mqtt",
 		Name:      "probe_duration_seconds",
 		Help:      "Returns how long the probe took to complete in seconds",
+		ConstLabels: prometheus.Labels{
+			"target": probe.Target,
+		},
 	})
 
 	registry := prometheus.NewRegistry()