metrics

cmd/go-temper/config.go

@@ -29,7 +29,7 @@ type configStructure struct {
 }
 
 type configPrometheus struct {
-	Temperature prometheus.Gauge
+	Temperature *prometheus.GaugeVec
 }
 
 var config = configStructure{
@@ -41,4 +41,14 @@ var config = configStructure{
 	WebSrvReadTimeout:  5,
 	WebSrvWriteTimeout: 2,
 	WebSrvIdleTimeout:  2,
+
+	Prometheus: configPrometheus{
+		Temperature: prometheus.NewGaugeVec(prometheus.GaugeOpts{
+			Namespace: "server_room",
+			Subsystem: "exhaust",
+			Name: "temp",
+			Help: "Temperature measured in the server room",
+		},
+		[]string{"unit"},
+	)},
 }

cmd/go-temper/main.go

@@ -5,6 +5,8 @@ import (
 	"os"
 	"os/signal"
 	"syscall"
+
+	"github.com/prometheus/client_golang/prometheus"
 )
 
 func forever() {
@@ -16,6 +18,10 @@ func forever() {
 }
 
 func main() {
+	prometheus.MustRegister(config.Prometheus.Temperature)
+	config.Prometheus.Temperature.With(prometheus.Labels{"unit": "celsius"}).Set(100)
+	config.Prometheus.Temperature.With(prometheus.Labels{"unit": "fahrenheit"}).Set(100)
+	config.Prometheus.Temperature.With(prometheus.Labels{"unit": "kelvin"}).Set(100)
 	go httpServer("0.0.0.0", 8080)
 	forever()