mcp and ucp

cmd/order/main.go

@@ -19,6 +19,7 @@ import (
 	"sync"
 	"time"
 
+	"git.k6n.net/mats/go-cart-actor/internal/ucp"
 	"git.k6n.net/mats/go-cart-actor/pkg/actor"
 	"git.k6n.net/mats/go-cart-actor/pkg/flow"
 	"git.k6n.net/mats/go-cart-actor/pkg/idempotency"
@@ -155,6 +156,15 @@ func main() {
 	mux.HandleFunc("POST /api/orders/{id}/returns", s.handleReturn)
 	mux.HandleFunc("POST /api/orders/{id}/refunds", s.handleRefund)
 
+	// UCP REST adapter — Universal Commerce Protocol order lifecycle.
+	orderUCP := ucp.OrderHandler(s.applier)
+	if signer := loadUCPOrderSigner(); signer != nil {
+		orderUCP = ucp.WithSigning(orderUCP, signer)
+		logger.Info("ucp signing enabled")
+	}
+	mux.Handle("/ucp/v1/orders", orderUCP)
+	mux.Handle("/ucp/v1/orders/", orderUCP)
+
 	// Saga / flow admin (backoffice editor).
 	mux.HandleFunc("GET /sagas/capabilities", s.handleCapabilities)
 	mux.HandleFunc("GET /sagas/flows", s.handleListFlows)
@@ -444,6 +454,26 @@ func selectProvider(logger *slog.Logger) order.PaymentProvider {
 	return order.NewMockProvider()
 }
 
+// loadUCPOrderSigner loads the UCP ECDSA signing key from the path specified in
+// the UCP_SIGNING_KEY_PATH environment variable. Returns nil if unset or unreadable.
+func loadUCPOrderSigner() *ucp.SigningConfig {
+	path := os.Getenv("UCP_SIGNING_KEY_PATH")
+	if path == "" {
+		return nil
+	}
+	pemData, err := os.ReadFile(path)
+	if err != nil {
+		log.Printf("ucp signing: cannot read key %s: %v", path, err)
+		return nil
+	}
+	cfg, err := ucp.NewSigningConfigFromPEM(pemData, "k6n-ecdsa-2026")
+	if err != nil {
+		log.Printf("ucp signing: invalid key at %s: %v", path, err)
+		return nil
+	}
+	return cfg
+}
+
 func envOr(key, def string) string {
 	if v := os.Getenv(key); v != "" {
 		return v