RCT: re-add connection sharing (#19379)

go.mod

@@ -222,4 +222,4 @@ replace github.com/grid-x/modbus => github.com/evcc-io/modbus v0.0.0-20241027151
 
 replace github.com/lorenzodonini/ocpp-go => github.com/evcc-io/ocpp-go v0.0.0-20241230132027-815870498cc3
 
-replace github.com/mlnoga/rct => github.com/andig/rct v0.1.2-0.20250303102452-38b496bdd2c9
+replace github.com/mlnoga/rct => github.com/andig/rct v0.1.2-0.20250303165133-baaf38f1674c

go.sum

@@ -39,8 +39,8 @@ github.com/andig/gosunspec v0.0.0-20240918203654-860ce51d602b h1:81UMfM949I7StrR
 github.com/andig/gosunspec v0.0.0-20240918203654-860ce51d602b/go.mod h1:c6P6szcR+ROkqZruOR4f6qbDKFjZX6OitPpj+yJ/r8k=
 github.com/andig/mbserver v0.0.0-20230310211055-1d29cbb5820e h1:m/NTP3JWpR7M0ljLxiQU4fzR25jjhe1LDtxLMNcoNJQ=
 github.com/andig/mbserver v0.0.0-20230310211055-1d29cbb5820e/go.mod h1:4VtYzTm//oUipwvO3yh0g/udTE7pYJM+U/kyAuFDsgM=
-github.com/andig/rct v0.1.2-0.20250303102452-38b496bdd2c9 h1:hHUPfKTJlyHX0i5iZy7UNtIYoNDtcPH/Q1bbOe2OZ+g=
-github.com/andig/rct v0.1.2-0.20250303102452-38b496bdd2c9/go.mod h1:KRjBDV8kuvGd2kJfN8/F0kjH8JjkFVpBpn7MhW+ACL8=
+github.com/andig/rct v0.1.2-0.20250303165133-baaf38f1674c h1:J3nV3DPhqZWuKsPDW4vbZ743O9lpRkNb06P2e6bnSgY=
+github.com/andig/rct v0.1.2-0.20250303165133-baaf38f1674c/go.mod h1:KRjBDV8kuvGd2kJfN8/F0kjH8JjkFVpBpn7MhW+ACL8=
 github.com/andig/yaml v0.0.0-20240531135838-1ff5761ab467 h1:JqIoHxsQSV39xaemvVRu3HOkSf5AbhQ1YEENJa2cL3Q=
 github.com/andig/yaml v0.0.0-20240531135838-1ff5761ab467/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 github.com/andybalholm/cascadia v1.3.3 h1:AG2YHrzJIm4BZ19iwJ/DAua6Btl3IwJX+VI4kktS1LM=

meter/rct.go

@@ -6,7 +6,6 @@ import (
 	"errors"
 	"fmt"
 	"math"
-	"math/rand/v2"
 	"strings"
 	"sync"
 	"time"
@@ -22,7 +21,10 @@ type RCT struct {
 	usage string          // grid, pv, battery
 }
 
-var rctMu sync.Mutex
+var (
+	rctMu    sync.Mutex
+	rctCache = make(map[string]*rct.Connection)
+)
 
 func init() {
 	registry.AddCtx("rct", NewRCTFromConfig)
@@ -56,19 +58,24 @@ func NewRCTFromConfig(ctx context.Context, other map[string]interface{}) (api.Me
 func NewRCT(ctx context.Context, uri, usage string, minSoc, maxSoc int, cache time.Duration, capacity func() float64) (api.Meter, error) {
 	log := util.NewLogger("rct")
 
-	// prevent concurrent connections
+	// re-use connections
 	rctMu.Lock()
-	time.Sleep(time.Duration(rand.Uint64N(uint64(time.Second))))
-	rctMu.Unlock()
-
-	conn, err := rct.NewConnection(ctx, uri, rct.WithErrorCallback(func(err error) {
+	conn, ok := rctCache[uri]
+	if !ok {
+		var err error
+		conn, err = rct.NewConnection(ctx, uri, rct.WithErrorCallback(func(err error) {
+			if err != nil {
+				log.ERROR.Println(err)
+			}
+		}), rct.WithLogger(log.TRACE.Printf), rct.WithTimeout(cache))
 		if err != nil {
-			log.ERROR.Println(err)
+			rctMu.Unlock()
+			return nil, err
 		}
-	}), rct.WithLogger(log.TRACE.Printf), rct.WithTimeout(cache))
-	if err != nil {
-		return nil, err
+
+		rctCache[uri] = conn
 	}
+	rctMu.Unlock()
 
 	m := &RCT{
 		usage: strings.ToLower(usage),

templates/definition/meter/rct-power.yaml

@@ -22,7 +22,7 @@ params:
     advanced: true
   - name: cache
     advanced: true
-    default: 5s
+    default: 10s
 render: |
   type: rct
   uri: {{ .host }}