more checkout

cmd/order/main.go

@@ -21,7 +21,9 @@ import (
 
 	"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"
 	"git.k6n.net/mats/go-cart-actor/pkg/order"
+	"git.k6n.net/mats/go-cart-actor/pkg/outbox"
 	messages "git.k6n.net/mats/go-cart-actor/proto/order"
 
 	"google.golang.org/protobuf/encoding/protojson"
@@ -39,6 +41,7 @@ type server struct {
 	provider    order.PaymentProvider
 	defaultFlow string
 	dataDir     string
+	idem        *idempotency.Store
 	logger      *slog.Logger
 }
 
@@ -94,10 +97,15 @@ func main() {
 	amqpURL := os.Getenv("AMQP_URL")
 	var emitPub order.Publisher
 	if amqpURL != "" {
-		if pub, err := newRabbitPublisher(amqpURL); err != nil {
-			logger.Warn("amqp_emit hook: publisher unavailable", "err", err)
+		// The amqp_emit hook writes to a durable outbox rather than the broker
+		// directly; a relay goroutine drains it to RabbitMQ (reconnecting), so an
+		// event survives a broker outage or a crash after the state change.
+		box, err := outbox.Open(filepath.Join(dataDir, "outbox.log"))
+		if err != nil {
+			logger.Warn("outbox disabled: open failed", "err", err)
 		} else {
-			emitPub = pub
+			go box.Run(context.Background(), newRabbitPublisher(amqpURL), 5*time.Second, logger)
+			emitPub = box
 		}
 	}
 	freg := flow.NewRegistry()
@@ -115,10 +123,18 @@ func main() {
 		log.Fatalf("load flows: %v", err)
 	}
 
+	// Durable idempotency store for order creation — survives a restart, so a
+	// client retry after a crash returns the existing order instead of creating
+	// a duplicate.
+	idem, err := idempotency.Open(filepath.Join(dataDir, "idempotency.log"))
+	if err != nil {
+		log.Fatalf("open idempotency store: %v", err)
+	}
+
 	s := &server{
 		pool: pool, applier: applier, storage: storage, reg: reg,
 		engine: engine, freg: freg, flows: flows, provider: provider,
-		defaultFlow: def.Name, dataDir: dataDir, logger: logger,
+		defaultFlow: def.Name, dataDir: dataDir, idem: idem, logger: logger,
 	}
 
 	mux := http.NewServeMux()