fix: get temperatures

pkg/logs/temperature.go

@@ -1,8 +1,9 @@
 package logs
 
 import (
-	"bufio"
+	"encoding/json"
 	"fmt"
+	"io/ioutil"
 	"os"
 	"path/filepath"
 
@@ -10,34 +11,79 @@ import (
 	"git.cryptic.systems/fh-trier/go-flucky/pkg/types"
 )
 
-// Temperature write a given array of temperatures to a logfile
-func Temperature(temperatures []*stypes.Temperature, config *types.Config) error {
+// AppendTemperature write a given array of temperatures to a logfile
+func AppendTemperature(temperatures []*stypes.Temperature, cnf *types.Config) error {
 
-	logPath := filepath.Dir(config.TemperatureLogfile)
-
-	// create log dir if not exist
-	if _, err := os.Stat(logPath); os.IsNotExist(err) {
-		err := os.MkdirAll(logPath, os.ModePerm)
-		if err != nil {
-			return fmt.Errorf("Can not create directory: %v", err)
-		}
-	}
-
-	f, err := os.OpenFile(config.TemperatureLogfile, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0644)
+	tLog, err := ReadTemperatures(cnf.TemperatureLogfile)
 	if err != nil {
 		return err
 	}
-	defer f.Close()
 
-	w := bufio.NewWriter(f)
+	tLog = append(tLog, temperatures...)
 
-	for _, temperature := range temperatures {
-		fmt.Fprintf(w, "%v\t%v\t%v\t%v\n", temperature.TemperatureID, temperature.TemperatureValue, temperature.TemperatureDate, temperature.SensorID)
-	}
-
-	err = w.Flush()
+	err = WriteTemperatures(tLog, cnf.TemperatureLogfile)
 	if err != nil {
-		return fmt.Errorf("Can not flush writer: %v", err)
+		return err
+	}
+
+	return nil
+}
+
+// FlushTemperatures ...
+func FlushTemperatures(logFile string) error {
+	if err := ioutil.WriteFile(logFile, []byte(""), 0644); err != nil {
+		return err
+	}
+	return nil
+}
+
+// ReadTemperatures ...
+func ReadTemperatures(logFile string) ([]*stypes.Temperature, error) {
+
+	logPath := filepath.Dir(logFile)
+
+	// create log dir if not exist
+	if _, err := os.Stat(logFile); os.IsNotExist(err) {
+		if _, err := os.Stat(logPath); os.IsNotExist(err) {
+			err := os.MkdirAll(logPath, os.ModePerm)
+			if err != nil {
+				return nil, fmt.Errorf("Can not create directory: %v", err)
+			}
+		}
+		if err := FlushTemperatures(logFile); err != nil {
+			return nil, err
+		}
+
+	}
+
+	// open config file
+	jsonFile, err := os.Open(logFile)
+	if err != nil {
+		return nil, fmt.Errorf("Can not open file %v: %v", logFile, err)
+	}
+	defer jsonFile.Close()
+
+	bytes, err := ioutil.ReadAll(jsonFile)
+	if err != nil {
+		return nil, fmt.Errorf("Can not read jsonfile %v: %v", logFile, err)
+	}
+
+	temperatures := []*stypes.Temperature{}
+	json.Unmarshal(bytes, &temperatures)
+
+	return temperatures, nil
+}
+
+// WriteTemperatures ...
+func WriteTemperatures(temperatures []*stypes.Temperature, logFile string) error {
+
+	bytes, err := json.Marshal(temperatures)
+	if err != nil {
+		return err
+	}
+
+	if err := ioutil.WriteFile(logFile, bytes, 0644); err != nil {
+		return err
 	}
 
 	return nil