Add sensor reading status metrics

README.md

@@ -2,6 +2,12 @@
 
 Control the temperature of your fermentation process.
 
+# TODO
+
+* Cooler should not have min runtime, but run till min. temp cool level
+  * E.g. cool until setpoint - 1 degrees is reached
+  * ...or just make the damned PID work
+
 # Epics
 
 ## Heater/Cooler

cmd/fermentord/config.go

@@ -57,7 +57,7 @@ func loadConfiguration() *controllers.ControllerConfig {
 }
 
 func reloadConfiguration(config *controllers.ControllerConfig, ctrl *controllers.ChamberController) {
-
+	log.Printf("Reloading configuration")
 	log.Printf("Ambient sensor: %v", config.Sensor.Ambient)
 	log.Printf("Chamber sensor: %v", config.Sensor.Chamber)
 	log.Printf("Wort sensor   : %v", config.Sensor.Wort)

internal/metrics/prometheus.go

@@ -31,16 +31,16 @@ var (
 		},
 	)
 
-	TemperatureSensorReadingDurationSeconds = promauto.NewHistogramVec(
+	TemperatureSensorReadingStatus = promauto.NewCounterVec(
-		prometheus.HistogramOpts{
+		prometheus.CounterOpts{
 			Namespace: "fermentord",
 			Subsystem: "temperature",
-			Name:      "sensor_reading_duration_seconds",
+			Name:      "sensor_reading_status",
-			Help:      "Duration of temperature sensor readings.",
+			Help:      "Temperature sensor reading status",
-			Buckets:   []float64{0.25, 0.5, 0.75, 1, 1.25, 1.5},
 		},
 		[]string{
 			"sensor",
+			"status",
 		},
 	)
 

pkg/temperature/ds18b20.go

@@ -104,14 +104,13 @@ func PollSensors(ctx context.Context, wg *sync.WaitGroup, readingInterval time.D
 
 func readSensors(hub *sentry.Hub) {
 	for _, sensor := range sensors {
-		start := time.Now()
 		t, err := read(sensor)
-		dur := time.Since(start).Seconds()
 
 		if err != nil {
 			accErrSensor[sensor]++
 			hub.CaptureException(err)
 			log.Printf("Error reading temperature sensor %v: %v", sensor, err)
+			metrics.TemperatureSensorReadingStatus.WithLabelValues(sensor, "failed").Inc()
 			continue
 		}
 
@@ -127,11 +126,9 @@ func readSensors(hub *sentry.Hub) {
 			WithLabelValues(sensor).
 			Set(r.Degrees())
 
-		metrics.TemperatureSensorReadingDurationSeconds.
-			WithLabelValues(sensor).
-			Observe(dur)
-
 		C <- r
+
+		metrics.TemperatureSensorReadingStatus.WithLabelValues(sensor, "ok").Inc()
 	}
 }