feat: import from sqlite or postgresql

pkg/repository/repository.go

@@ -2,6 +2,7 @@ package repository
 
 import (
 	"context"
+	"fmt"
 	"net/url"
 	"strings"
 
@@ -214,3 +215,94 @@ func New(dsnURL *url.URL, flogger logger.Logger) (*Repository, error) {
 		database: database,
 	}, nil
 }
+
+type OptImport struct {
+	Sensors      bool
+	Humidities   bool
+	Pressures    bool
+	Temperatures bool
+}
+
+func Import(sourceDSNURL *url.URL, destDNSURL *url.URL, flogger logger.Logger, optImport OptImport) error {
+
+	importMap := map[string]bool{
+		"humidities":   optImport.Humidities,
+		"pressures":    optImport.Pressures,
+		"temperatures": optImport.Temperatures,
+	}
+
+	// enable sensors if one measured value is enabled
+	if !optImport.Sensors {
+		for key, value := range importMap {
+			if value {
+				flogger.Info("Enable import option sensors. It's required as foreign key for %v", key)
+				optImport.Sensors = true
+			}
+		}
+	}
+
+	sourceRepo, err := New(sourceDSNURL, flogger)
+	if err != nil {
+		return fmt.Errorf("Failed to open the source repo: %w", err)
+	}
+	defer sourceRepo.Close()
+
+	destRepo, err := New(destDNSURL, flogger)
+	if err != nil {
+		return fmt.Errorf("Failed to open the destination repo: %w", err)
+	}
+	defer destRepo.Close()
+
+	ctx := context.Background()
+	devices, err := sourceRepo.database.SelectDevices(ctx)
+	if err != nil {
+		return fmt.Errorf("Failed to fetch devices from source repo: %w", err)
+	}
+
+	flogger.Debug("Found %v devices", len(devices))
+
+	for i := range devices {
+		err := destRepo.AddDevices(devices[i])
+		if err != nil {
+			return fmt.Errorf("Failed to add device %v into dest repo: %w", devices[i].Name, err)
+		}
+	}
+
+	if optImport.Sensors {
+		sensors, err := sourceRepo.database.SelectSensors(ctx)
+		if err != nil {
+			return fmt.Errorf("Failed to fetch sensors from source repo: %w", err)
+		}
+
+		flogger.Debug("Found %v sensors", len(sensors))
+
+		for i := range sensors {
+			err := destRepo.AddSensors(sensors[i])
+			if err != nil {
+				return fmt.Errorf("Failed to add sensor %v into dest repo: %w", sensors[i].Name, err)
+			}
+		}
+	}
+
+	for key, f := range map[string]func(context.Context) ([]*types.MeasuredValue, error){
+		"humidities":   sourceRepo.database.SelectHumidities,
+		"pressures":    sourceRepo.database.SelectPressures,
+		"temperatures": sourceRepo.database.SelectTemperatures,
+	} {
+		if importMap[key] {
+			measuredValues, err := f(ctx)
+			if err != nil {
+				return fmt.Errorf("Failed to select %v from source repo: %w", key, err)
+			}
+
+			flogger.Debug("Found %v %v values", len(measuredValues), key)
+
+			err = destRepo.AddMeasuredValues(measuredValues...)
+			if err != nil {
+				return fmt.Errorf("Failed to add %v into dest repo: %w", key, err)
+			}
+		}
+	}
+
+	return nil
+}