refactor(plc4go): avoid panics if possible

plc4go/internal/ads/Discoverer.go

@@ -23,6 +23,7 @@ import (
 	"context"
 	"encoding/binary"
 	"fmt"
+	"github.com/pkg/errors"
 	"net"
 	"net/url"
 	"strconv"
@@ -131,11 +132,11 @@ func (d *Discoverer) Discover(ctx context.Context, callback func(event apiModel.
 	for _, discoveryItem := range discoveryItems {
 		responseAddr, err := net.ResolveUDPAddr("udp4", fmt.Sprintf("%s:%d", discoveryItem.localAddress, model.AdsDiscoveryConstants_ADSDISCOVERYUDPDEFAULTPORT))
 		if err != nil {
-			panic(err)
+			return errors.Wrap(err, "error resolving udp")
 		}
 		socket, err := net.ListenUDP("udp4", responseAddr)
 		if err != nil {
-			panic(err)
+			return errors.Wrap(err, "error listening udp")
 		}
 		discoveryItem.socket = socket
 

plc4go/internal/ads/model/Tag.go

@@ -158,7 +158,7 @@ func (m DirectPlcTag) SerializeWithWriteBuffer(writeBuffer utils.WriteBuffer) er
 }
 
 func (m DirectPlcTag) MarshalXMLAttr(name xml.Name) (xml.Attr, error) {
-	panic(name)
+	return xml.Attr{}, errors.Errorf("%s", name) // TODO: why did this panic before
 }
 
 type SymbolicPlcTag struct {

plc4go/internal/cbus/CBusMessageMapper.go

@@ -96,7 +96,8 @@ func TagToCBusMessage(tag apiModel.PlcTag, value apiValues.PlcValue, alphaGenera
 		var salData readWriteModel.SALData
 		switch tagType.application.ApplicationId() {
 		case readWriteModel.ApplicationId_FREE_USAGE:
-			panic("Not yet implemented") // TODO: implement
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		case readWriteModel.ApplicationId_TEMPERATURE_BROADCAST:
 			var temperatureBroadcastData readWriteModel.TemperatureBroadcastData
 			switch salCommand {
@@ -114,7 +115,8 @@ func TagToCBusMessage(tag apiModel.PlcTag, value apiValues.PlcValue, alphaGenera
 			}
 			salData = readWriteModel.NewSALDataTemperatureBroadcast(temperatureBroadcastData, nil)
 		case readWriteModel.ApplicationId_ROOM_CONTROL_SYSTEM:
-			panic("Implement me")
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		case
 			readWriteModel.ApplicationId_LIGHTING,
 			readWriteModel.ApplicationId_VENTILATION,
@@ -166,35 +168,48 @@ func TagToCBusMessage(tag apiModel.PlcTag, value apiValues.PlcValue, alphaGenera
 				lightingData = readWriteModel.NewLightingDataTerminateRamp(group, commandTypeContainer)
 				supportsWrite = true
 			case readWriteModel.LightingCommandType_LABEL.PLC4XEnumName():
-				panic("Implement me")
+				err = errors.New("Not yet implemented") // TODO: implement
+				return
 			default:
 				return nil, false, false, false, errors.Errorf("Unsupported command %s for %s", salCommand, tagType.application.ApplicationId())
 			}
 			salData = readWriteModel.NewSALDataLighting(lightingData, nil)
 		case readWriteModel.ApplicationId_AIR_CONDITIONING:
-			panic("Implement me")
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		case readWriteModel.ApplicationId_TRIGGER_CONTROL:
-			panic("Implement me")
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		case readWriteModel.ApplicationId_ENABLE_CONTROL:
-			panic("Implement me")
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		case readWriteModel.ApplicationId_SECURITY:
-			panic("Implement me")
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		case readWriteModel.ApplicationId_METERING:
-			panic("Implement me")
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		case readWriteModel.ApplicationId_ACCESS_CONTROL:
-			panic("Implement me")
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		case readWriteModel.ApplicationId_CLOCK_AND_TIMEKEEPING:
-			panic("Implement me")
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		case readWriteModel.ApplicationId_TELEPHONY_STATUS_AND_CONTROL:
-			panic("Implement me")
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		case readWriteModel.ApplicationId_MEASUREMENT:
-			panic("Implement me")
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		case readWriteModel.ApplicationId_TESTING:
-			panic("Implement me")
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		case readWriteModel.ApplicationId_MEDIA_TRANSPORT_CONTROL:
-			panic("Implement me")
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		case readWriteModel.ApplicationId_ERROR_REPORTING:
-			panic("Implement me")
+			err = errors.New("Not yet implemented") // TODO: implement
+			return
 		default:
 			return nil, false, false, false, errors.Errorf("No support for %s", tagType.application)
 		}

plc4go/internal/cbus/TagHandler.go

@@ -145,8 +145,8 @@ func (m TagHandler) handleStatusRequestPattern(match map[string]string) (apiMode
 		} else if levelArgument := match["startingGroupAddressLabel"]; levelArgument != "" {
 			statusRequestType = StatusRequestTypeLevel
 			decodedHex, _ := hex.DecodeString(levelArgument)
-			if len(decodedHex) != 1 {
-				panic("invalid state. Should have exactly 1")
+			if hexLength := len(decodedHex); hexLength != 1 {
+				return nil, errors.Errorf("invalid state. Should have exactly 1. Actual length %d", hexLength)
 			}
 			startingGroupAddressLabel = &decodedHex[0]
 		} else {
@@ -177,7 +177,7 @@ func (m TagHandler) handleCalPattern(match map[string]string) (apiModel.PlcTag,
 	calTypeArgument := match["calType"]
 	switch {
 	case strings.HasPrefix(calTypeArgument, "reset"):
-		panic("Not implemented") // TODO: implement me
+		return nil, errors.New("Not implemented") // TODO: implement me
 	case strings.HasPrefix(calTypeArgument, "recall="):
 		var recalParamNo readWriteModel.Parameter
 		recallParamNoArgument := match["recallParamNo"]
@@ -263,15 +263,15 @@ func (m TagHandler) handleCalPattern(match map[string]string) (apiModel.PlcTag,
 		count = uint8(atoi)
 		return NewCALGetStatusTag(unitAddress, bridgeAddresses, recalParamNo, count, 1), nil
 	case strings.HasPrefix(calTypeArgument, "write="):
-		panic("Not implemented") // TODO: implement me
+		return nil, errors.New("Not implemented") // TODO: implement me
 	case strings.HasPrefix(calTypeArgument, "identifyReply="):
-		panic("Not implemented") // TODO: implement me
+		return nil, errors.New("Not implemented") // TODO: implement me
 	case strings.HasPrefix(calTypeArgument, "reply="):
-		panic("Not implemented") // TODO: implement me
+		return nil, errors.New("Not implemented") // TODO: implement me
 	case strings.HasPrefix(calTypeArgument, "status="):
-		panic("Not implemented") // TODO: implement me
+		return nil, errors.New("Not implemented") // TODO: implement me
 	case strings.HasPrefix(calTypeArgument, "statusExtended="):
-		panic("Not implemented") // TODO: implement me
+		return nil, errors.New("Not implemented") // TODO: implement me
 	default:
 		return nil, errors.Errorf("Invalid cal type %s", calTypeArgument)
 	}