OpenWB Pro: add caching (#2731)

charger/openwb-pro.go

@@ -6,6 +6,7 @@ import (
 	"time"
 
 	"github.com/evcc-io/evcc/api"
+	"github.com/evcc-io/evcc/charger/openwb/pro"
 	"github.com/evcc-io/evcc/util"
 	"github.com/evcc-io/evcc/util/request"
 )
@@ -16,53 +17,39 @@ func init() {
 
 // https://openwb.de/main/?page_id=771
 
-type openwbProStatus struct {
-	Date           string
-	Timestamp      int64
-	Currents       []float64
-	Powers         []float64
-	PowerAll       float64 `json:"power_all"`
-	Imported       float64
-	Exported       float64
-	PlugState      bool    `json:"plug_state"`
-	ChargeState    bool    `json:"charge_state"`
-	PhasesActual   int     `json:"phases_actual"`
-	PhasesTarget   int     `json:"phases_target"`
-	PhasesInUse    int     `json:"phases_in_use"`
-	OfferedCurrent float64 `json:"offered_current"`
-	EvseSignaling  string  `json:"evse_signaling"`
-	VehicleID      string  `json:"vehicle_id"`
-	Serial         string
-}
-
 // OpenWBPro charger implementation
 type OpenWBPro struct {
 	*request.Helper
 	uri     string
 	current float64
+	status  pro.Status
+	updated time.Time
+	cache   time.Duration
 }
 
 // NewOpenWBProFromConfig creates a OpenWBPro charger from generic config
 func NewOpenWBProFromConfig(other map[string]interface{}) (api.Charger, error) {
 	cc := struct {
-		URI string
+		URI   string
+		Cache time.Duration
 	}{}
 
 	if err := util.DecodeOther(other, &cc); err != nil {
 		return nil, err
 	}
 
-	return NewOpenWBPro(util.DefaultScheme(cc.URI, "http"))
+	return NewOpenWBPro(util.DefaultScheme(cc.URI, "http"), cc.Cache)
 }
 
 // NewOpenWBPro creates OpenWBPro charger
-func NewOpenWBPro(uri string) (*OpenWBPro, error) {
+func NewOpenWBPro(uri string, cache time.Duration) (*OpenWBPro, error) {
 	log := util.NewLogger("owbpro")
 
 	wb := &OpenWBPro{
 		Helper:  request.NewHelper(log),
 		uri:     strings.TrimRight(uri, "/"),
 		current: 6, // 6A defined value
+		cache:   cache,
 	}
 
 	go wb.hearbeat(log)
@@ -78,10 +65,19 @@ func (wb *OpenWBPro) hearbeat(log *util.Logger) {
 	}
 }
 
-func (wb *OpenWBPro) get() (openwbProStatus, error) {
-	var res openwbProStatus
+func (wb *OpenWBPro) get() (pro.Status, error) {
+	if time.Since(wb.updated) < wb.cache {
+		return wb.status, nil
+	}
+
+	var res pro.Status
 	uri := fmt.Sprintf("%s/%s", wb.uri, "connect.php")
 	err := wb.GetJSON(uri, &res)
+	if err == nil {
+		wb.updated = time.Now()
+		wb.status = res
+	}
+
 	return res, err
 }
 
@@ -91,6 +87,7 @@ func (wb *OpenWBPro) set(payload string) error {
 	if err == nil {
 		resp.Body.Close()
 	}
+	wb.updated = time.Time{}
 	return err
 }
 

charger/openwb/pro/types.go

@@ -0,0 +1,22 @@
+package pro
+
+// https://openwb.de/main/?page_id=771
+
+type Status struct {
+	Date           string
+	Timestamp      int64
+	Currents       []float64
+	Powers         []float64
+	PowerAll       float64 `json:"power_all"`
+	Imported       float64
+	Exported       float64
+	PlugState      bool    `json:"plug_state"`
+	ChargeState    bool    `json:"charge_state"`
+	PhasesActual   int     `json:"phases_actual"`
+	PhasesTarget   int     `json:"phases_target"`
+	PhasesInUse    int     `json:"phases_in_use"`
+	OfferedCurrent float64 `json:"offered_current"`
+	EvseSignaling  string  `json:"evse_signaling"`
+	VehicleID      string  `json:"vehicle_id"`
+	Serial         string
+}