feat(multiplayer): wire production proposal outbox delivery

server/api/outbox.go

@@ -0,0 +1,85 @@
+package api
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"github.com/cosmic-clash/cosmic-clash/server/store"
+)
+
+// RunProposalOutboxDispatcher delivers committed proposal changes to the
+// authenticated WebSocket subscribers. It only reads proposal_changed rows;
+// result and other outbox event types remain owned by their own consumers.
+// Delivery is at-least-once because the row is acknowledged only after every
+// participant publication succeeds.
+func RunProposalOutboxDispatcher(ctx context.Context, db *sql.DB, service *Service) {
+	if db == nil || service == nil {
+		return
+	}
+	ticker := time.NewTicker(100 * time.Millisecond)
+	defer ticker.Stop()
+	dispatcher := store.NewOutboxDispatcher(db, func(deliveryCtx context.Context, event store.OutboxEvent) error {
+		return deliverProposalOutboxEvent(deliveryCtx, event, service)
+	})
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-ticker.C:
+			events, err := store.ReadUnpublishedProposalOutbox(ctx, db, 100)
+			if err != nil {
+				continue
+			}
+			_ = dispatchOutboxEvents(ctx, dispatcher, events)
+		}
+	}
+}
+
+func dispatchOutboxEvents(ctx context.Context, dispatcher *store.OutboxDispatcher, events []store.OutboxEvent) error {
+	if len(events) == 0 {
+		return nil
+	}
+	// Use the same delivery-before-ack contract as the general dispatcher,
+	// while keeping the already-filtered batch from being read a second time.
+	for _, event := range events {
+		if event.EventID == "" {
+			return fmt.Errorf("outbox event has no ID")
+		}
+		if err := dispatcher.Deliver(ctx, event); err != nil {
+			return err
+		}
+		if err := dispatcher.Ack(ctx, event.EventID, time.Now().UTC()); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func deliverProposalOutboxEvent(_ context.Context, event store.OutboxEvent, service *Service) error {
+	var envelope struct {
+		Event      string    `json:"event"`
+		Revision   uint64    `json:"revision"`
+		ResourceID string    `json:"resource_id"`
+		OccurredAt time.Time `json:"occurred_at"`
+		State      string    `json:"state"`
+		PlayerIDs  []string  `json:"player_ids"`
+	}
+	if err := json.Unmarshal(event.Payload, &envelope); err != nil {
+		return fmt.Errorf("decode proposal outbox event: %w", err)
+	}
+	if envelope.Event != "proposal_changed" || envelope.ResourceID == "" || len(envelope.PlayerIDs) == 0 {
+		return fmt.Errorf("invalid proposal outbox event")
+	}
+	for _, playerID := range envelope.PlayerIDs {
+		if err := service.PublishControlPlaneEvent(ControlPlaneEvent{
+			Event: envelope.Event, Revision: envelope.Revision, ResourceID: envelope.ResourceID,
+			OccurredAt: envelope.OccurredAt, State: envelope.State, PlayerID: playerID,
+		}); err != nil {
+			return err
+		}
+	}
+	return nil
+}

server/api/outbox_test.go

@@ -0,0 +1,51 @@
+package api
+
+import (
+	"context"
+	"encoding/json"
+	"testing"
+	"time"
+
+	"github.com/cosmic-clash/cosmic-clash/server/store"
+)
+
+func TestDeliverProposalOutboxEventPublishesEveryTarget(t *testing.T) {
+	service := &Service{}
+	first := service.getEventHub().subscribe("player-a")
+	second := service.getEventHub().subscribe("player-b")
+	defer service.getEventHub().unsubscribe(first)
+	defer service.getEventHub().unsubscribe(second)
+
+	payload, err := json.Marshal(map[string]any{
+		"event": "proposal_changed", "revision": uint64(0), "resource_id": "proposal-1",
+		"occurred_at": time.Unix(1000, 0).UTC(), "state": "OPEN", "player_ids": []string{"player-a", "player-b"},
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := deliverProposalOutboxEvent(context.Background(), store.OutboxEvent{EventID: "event-1", Payload: payload}, service); err != nil {
+		t.Fatalf("deliver proposal event: %v", err)
+	}
+	for name, subscriber := range map[string]*eventSubscriber{"player-a": first, "player-b": second} {
+		select {
+		case <-subscriber.queue:
+		case <-time.After(time.Second):
+			t.Fatalf("%s did not receive targeted proposal event", name)
+		}
+	}
+}
+
+func TestDeliverProposalOutboxEventRejectsMalformedOrUntargetedRows(t *testing.T) {
+	service := &Service{}
+	for name, event := range map[string]store.OutboxEvent{
+		"malformed":      {Payload: []byte("{")},
+		"wrong event":    {Payload: []byte(`{"event":"match_completed","resource_id":"match-1","player_ids":["player-a"]}`)},
+		"missing target": {Payload: []byte(`{"event":"proposal_changed","resource_id":"proposal-1","player_ids":[]}`)},
+	} {
+		t.Run(name, func(t *testing.T) {
+			if err := deliverProposalOutboxEvent(context.Background(), event, service); err == nil {
+				t.Fatal("malformed or untargeted event accepted")
+			}
+		})
+	}
+}