Speed up loading temperatures

l3akage · Apr 15, 2019 · 8ff6e59 · 8ff6e59
1 parent 1b83ba3
commit 8ff6e59
Showing 1 changed file with 57 additions and 36 deletions.
diff --git a/onewire_collector.go b/onewire_collector.go
@@ -7,6 +7,7 @@ import (
 	"regexp"
 	"strconv"
 	"strings"
+	"sync"
 
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/common/log"
@@ -32,55 +33,75 @@ type Temp struct {
 type onewireCollector struct {
 }
 
-func getTemperatures() ([]Temp, error) {
+func getTemperatureFromDevice(device os.FileInfo) Temp {
 	reg, err := regexp.Compile("[^0-9]+")
 	if err != nil {
 		log.Fatal(err)
 	}
+	for i := 1; i <= 5; i++ {
+		content, err := ioutil.ReadFile("/sys/bus/w1/devices/" + device.Name() + "/w1_slave")
+		if err != nil {
+			log.Infof("Error reading device %s\n", device.Name())
+			continue
+		}
+		lines := strings.Split(string(content), "\n")
+		if len(lines) != 3 {
+			log.Infof("Unknown format for device %s\n", device.Name())
+			continue
+		}
+		if !strings.Contains(lines[0], "YES") {
+			log.Infof("CRC invalid for device %s\n", device.Name())
+			continue
+		}
+		data := strings.SplitAfter(lines[1], "t=")
+		if len(data) != 2 {
+			log.Infof("Temp value not found for device %s\n", device.Name())
+			continue
+		}
+		strValue := reg.ReplaceAllString(data[1], "")
+
+		tempInt, err := strconv.ParseFloat(strValue, 64)
+		if err != nil {
+			continue
+		}
+		if tempInt == 85000 {
+			continue
+		}
+		return Temp{
+			ID:    device.Name(),
+			Value: tempInt / 1000.0,
+		}
+	}
+	return Temp{}
+}
+
+func getTemperatures() ([]Temp, error) {
 	devices, err := ioutil.ReadDir("/sys/bus/w1/devices/")
 	if err != nil {
 		return nil, err
 	}
-	var values []Temp
+	var wg sync.WaitGroup
+	valueChan := make(chan Temp)
 	for _, device := range devices {
 		if _, err := os.Stat("/sys/bus/w1/devices/" + device.Name() + "/w1_slave"); err != nil {
 			continue
 		}
-		for i := 1; i <= 5; i++ {
-			content, err := ioutil.ReadFile("/sys/bus/w1/devices/" + device.Name() + "/w1_slave")
-			if err != nil {
-				log.Infof("Error reading device %s\n", device.Name())
-				continue
-			}
-			lines := strings.Split(string(content), "\n")
-			if len(lines) != 3 {
-				log.Infof("Unknown format for device %s\n", device.Name())
-				continue
-			}
-			if !strings.Contains(lines[0], "YES") {
-				log.Infof("CRC invalid for device %s\n", device.Name())
-				continue
-			}
-			data := strings.SplitAfter(lines[1], "t=")
-			if len(data) != 2 {
-				log.Infof("Temp value not found for device %s\n", device.Name())
-				continue
-			}
-			strValue := reg.ReplaceAllString(data[1], "")
-
-			tempInt, err := strconv.ParseFloat(strValue, 64)
-			if err != nil {
-				continue
-			}
-			if tempInt == 85000 {
-				continue
-			}
-			values = append(values, Temp{
-				ID:    device.Name(),
-				Value: tempInt / 1000.0,
-			})
-			break
+		wg.Add(1)
+		go func(device os.FileInfo) {
+			defer wg.Done()
+			valueChan <- getTemperatureFromDevice(device)
+		}(device)
+	}
+	go func() {
+		wg.Wait()
+		close(valueChan)
+	}()
+	var values []Temp
+	for t := range valueChan {
+		if t == (Temp{}) {
+			continue
 		}
+		values = append(values, t)
 	}
 	return values, nil
 }