Ocpp: process meter values in order (#15623)

charger/ocpp/connector_core.go

@@ -60,7 +60,7 @@ func (conn *Connector) MeterValues(request *core.MeterValuesRequest) (*core.Mete
 		conn.txnId = *request.TransactionId
 	}
 
-	for _, meterValue := range request.MeterValue {
+	for _, meterValue := range sortByAge(request.MeterValue) {
 		// ignore old meter value requests
 		if meterValue.Timestamp.Time.After(conn.meterUpdated) {
 			for _, sample := range meterValue.SampledValue {

charger/ocpp/helper.go

@@ -1,9 +1,11 @@
 package ocpp
 
 import (
+	"slices"
 	"time"
 
 	"github.com/evcc-io/evcc/api"
+	"github.com/lorenzodonini/ocpp-go/ocpp1.6/types"
 )
 
 // Wait waits for a CP roundtrip with timeout
@@ -18,3 +20,16 @@ func Wait(err error, rc chan error, timeout time.Duration) error {
 	}
 	return err
 }
+
+func sortByAge(values []types.MeterValue) []types.MeterValue {
+	return slices.SortedFunc(slices.Values(values), func(a, b types.MeterValue) int {
+		var at, bt time.Time
+		if a.Timestamp != nil {
+			at = a.Timestamp.Time
+		}
+		if b.Timestamp != nil {
+			bt = b.Timestamp.Time
+		}
+		return at.Compare(bt)
+	})
+}

charger/ocpp/helper_test.go

@@ -0,0 +1,23 @@
+package ocpp
+
+import (
+	"testing"
+	"time"
+
+	"github.com/lorenzodonini/ocpp-go/ocpp1.6/types"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestSortByAge(t *testing.T) {
+	assert.Equal(t, []types.MeterValue{
+		{Timestamp: nil},
+		{Timestamp: types.NewDateTime(time.UnixMilli(1))},
+		{Timestamp: types.NewDateTime(time.UnixMilli(2))},
+		{Timestamp: types.NewDateTime(time.UnixMilli(3))},
+	}, sortByAge([]types.MeterValue{
+		{Timestamp: types.NewDateTime(time.UnixMilli(3))},
+		{Timestamp: types.NewDateTime(time.UnixMilli(1))},
+		{Timestamp: nil},
+		{Timestamp: types.NewDateTime(time.UnixMilli(2))},
+	}))
+}