Add meter plugin (#21477)

plugin/meter.go

@@ -0,0 +1,72 @@
+package plugin
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/evcc-io/evcc/api"
+	meter "github.com/evcc-io/evcc/meter/config"
+	"github.com/evcc-io/evcc/util"
+	"github.com/evcc-io/evcc/util/config"
+)
+
+type meterPlugin struct {
+	meter  api.Meter
+	method Method
+}
+
+func init() {
+	registry.AddCtx("meter", NewMeterFromConfig)
+}
+
+// NewMeterFromConfig creates type conversion provider
+func NewMeterFromConfig(ctx context.Context, other map[string]interface{}) (Plugin, error) {
+	var cc struct {
+		Config config.Typed
+		Method
+	}
+
+	if err := util.DecodeOther(other, &cc); err != nil {
+		return nil, err
+	}
+
+	meter, err := meter.NewFromConfig(ctx, cc.Config.Type, cc.Config.Other)
+	if err != nil {
+		return nil, err
+	}
+
+	o := &meterPlugin{
+		meter:  meter,
+		method: cc.Method,
+	}
+
+	return o, nil
+}
+
+var _ FloatGetter = (*meterPlugin)(nil)
+
+func (o *meterPlugin) FloatGetter() (func() (float64, error), error) {
+	err := fmt.Errorf("unsupported method: %s", o.method.String())
+
+	switch o.method {
+	case Energy:
+		if _, ok := o.meter.(api.MeterEnergy); !ok {
+			return nil, err
+		}
+	case Soc:
+		if _, ok := o.meter.(api.Battery); !ok {
+			return nil, err
+		}
+	}
+
+	return func() (float64, error) {
+		switch o.method {
+		case Energy:
+			return o.meter.(api.MeterEnergy).TotalEnergy()
+		case Soc:
+			return o.meter.(api.Battery).Soc()
+		default:
+			return o.meter.CurrentPower()
+		}
+	}, nil
+}