Add workaround for invalid MEB measurements (#88)

The PMCC EVSE can connect to MEB EVs via ISO and then uses the EV as NTP
server. Sadly that server reports the wrong time and thus all
measurements are invalid.

This commit adds a workaround to test if the measurement is within 1
minute if the time is shifted by 1 or 2 hours.

Author: DerAndereAndi

usecases/cem/evcem/public.go

@@ -65,7 +65,7 @@ func (e *EVCEM) CurrentPerPhase(entity spineapi.EntityRemoteInterface) ([]float6
 
 	var result []float64
 	refetch := true
-	compare := time.Now().Add(-1 * time.Minute)
+	compare := time.Now().UTC().Add(-1 * time.Minute)
 
 	for _, phase := range ucapi.PhaseNameMapping {
 		for _, item := range data {
@@ -85,7 +85,18 @@ func (e *EVCEM) CurrentPerPhase(entity spineapi.EntityRemoteInterface) ([]float6
 			phaseValue := item.Value.GetValue()
 			result = append(result, phaseValue)
 
-			if item.Timestamp != nil {
+			if item.Timestamp == nil {
+				continue
+			}
+
+			if timestamp, err := item.Timestamp.GetTime(); err == nil {
+				refetch = timestamp.Before(compare)
+			}
+
+			// the MEB cars report the wrong NTP time by 1 or 2 hours (depending on DST)
+			// and PMCC uses NTP from the EV, so check these cases as well
+			for i := 0; i < 2 && refetch; i++ {
+				compare = compare.Add(-1 * time.Hour)
 				if timestamp, err := item.Timestamp.GetTime(); err == nil {
 					refetch = timestamp.Before(compare)
 				}

usecases/cem/evcem/public_test.go

@@ -1,6 +1,8 @@
 package evcem
 
 import (
+	"time"
+
 	"github.com/enbility/spine-go/model"
 	"github.com/enbility/spine-go/util"
 	"github.com/stretchr/testify/assert"
@@ -111,6 +113,61 @@ func (s *CemEVCEMSuite) Test_EVCurrentPerPhase() {
 	data, err = s.sut.CurrentPerPhase(s.evEntity)
 	assert.Nil(s.T(), err)
 	assert.Equal(s.T(), 10.0, data[0])
+
+	now := time.Now().Add(-50 * time.Second)
+
+	measData = &model.MeasurementListDataType{
+		MeasurementData: []model.MeasurementDataType{
+			{
+				MeasurementId: util.Ptr(model.MeasurementIdType(0)),
+				Value:         model.NewScaledNumberType(10),
+				Timestamp:     model.NewAbsoluteOrRelativeTimeTypeFromTime(now),
+			},
+		},
+	}
+
+	fErr = rFeature.UpdateData(model.FunctionTypeMeasurementListData, measData, nil, nil)
+	assert.Nil(s.T(), fErr)
+
+	data, err = s.sut.CurrentPerPhase(s.evEntity)
+	assert.Nil(s.T(), err)
+	assert.Equal(s.T(), 10.0, data[0])
+
+	now = now.Add(-1 * time.Hour)
+	measData = &model.MeasurementListDataType{
+		MeasurementData: []model.MeasurementDataType{
+			{
+				MeasurementId: util.Ptr(model.MeasurementIdType(0)),
+				Value:         model.NewScaledNumberType(10),
+				Timestamp:     model.NewAbsoluteOrRelativeTimeTypeFromTime(now),
+			},
+		},
+	}
+
+	fErr = rFeature.UpdateData(model.FunctionTypeMeasurementListData, measData, nil, nil)
+	assert.Nil(s.T(), fErr)
+
+	data, err = s.sut.CurrentPerPhase(s.evEntity)
+	assert.Nil(s.T(), err)
+	assert.Equal(s.T(), 10.0, data[0])
+
+	now = now.Add(-1 * time.Hour)
+	measData = &model.MeasurementListDataType{
+		MeasurementData: []model.MeasurementDataType{
+			{
+				MeasurementId: util.Ptr(model.MeasurementIdType(0)),
+				Value:         model.NewScaledNumberType(10),
+				Timestamp:     model.NewAbsoluteOrRelativeTimeTypeFromTime(now),
+			},
+		},
+	}
+
+	fErr = rFeature.UpdateData(model.FunctionTypeMeasurementListData, measData, nil, nil)
+	assert.Nil(s.T(), fErr)
+
+	data, err = s.sut.CurrentPerPhase(s.evEntity)
+	assert.Nil(s.T(), err)
+	assert.Equal(s.T(), 10.0, data[0])
 }
 
 func (s *CemEVCEMSuite) Test_EVPowerPerPhase_Power() {