feat(multiplayer): publish allocation progress events

multiplayer-next.md

@@ -1449,6 +1449,8 @@ Allocator-selected region, build, protocol, and transport now travel with the al
 
 The same allocation path now carries the matcher-selected playlist, preventing a ranked match from inheriting the Fleet’s casual default. Durable allocation claims return the playlist, the worker includes it in Fleet selection metadata, Agones copies it to the allocated GameServer, and the supervisor overrides `--playlist` before launch; the existing compatibility tests remain green.
 
+The allocator’s durable bind now increments the match revision and writes a participant-targeted `state_changed(ALLOCATING)` outbox event in the same serializable transaction as the server binding and ticket transitions, so clients can recover allocation progress after a delivery outage.
+
 Ranked proposal admission no longer trusts the matcher’s `--ranked-random-arena` boolean. The Go domain now owns a named allowlist for the three floor-goal `ArenaRegistry` entries, and rejects unknown and elevated IDs before any proposal is created.
 
 The arena hand-off is now durable: the matcher deterministically selects an eligible floor-goal arena from the proposal ID, migration 0008 stores that path on proposals and matches and enforces it for new direct SQL writes, migration 0009 retains it on provider allocations, domain/store/provider boundaries and recovery lookups recheck the same allowlist, allocation claims and idempotency digests retain it, Agones applies it as a match-scoped annotation, and the supervisor overlays the allocated child’s `--arena-path`. Godot accepts only the same floor-goal `ArenaRegistry` paths and requires one for allocated ranked matches, so a stale Fleet default, an elevated variant, or an altered retry cannot substitute a ranked arena. The recovery worker also rejects a provider-recovered allocation whose arena differs from the durable request before recording or binding it.

server/store/allocation_match_sql.go

@@ -39,8 +39,8 @@ WHERE mp.match_id = $1
 ORDER BY q.client_build`
 
 const BindAllocatedMatchParticipantsSQL = `WITH bound AS (
-    UPDATE matches
-    SET server_id = $3
+	UPDATE matches
+	SET server_id = $3, revision = revision + 1
     WHERE match_id = $1 AND state = 'ALLOCATING' AND allocation_id = $2 AND server_id IS NULL
       AND EXISTS (
           SELECT 1 FROM allocations
@@ -58,7 +58,7 @@ const BindAllocatedMatchParticipantsSQL = `WITH bound AS (
     WHERE q.ticket_id = p.ticket_id AND q.player_id = p.player_id AND q.state = 'ACCEPTED'
     RETURNING q.ticket_id
 )
-SELECT (SELECT count(*) FROM participants), (SELECT count(*) FROM advanced)`
+	SELECT (SELECT count(*) FROM participants), (SELECT count(*) FROM advanced), COALESCE((SELECT revision FROM bound), -1)`
 
 const ReleaseAllocatedMatchClaimSQL = `UPDATE matches
 SET allocation_id = NULL, allocation_claimed_at = NULL
@@ -245,18 +245,47 @@ func ClaimAllocatingMatch(ctx context.Context, db *sql.DB, transport string, now
 }
 
 func BindAllocatedMatch(ctx context.Context, db *sql.DB, allocation domain.Allocation) error {
-	if db == nil || allocation.MatchID == "" || allocation.AllocationID == "" || allocation.ServerID == "" || allocation.State != domain.ServerAllocated {
+	if db == nil || allocation.MatchID == "" || allocation.AllocationID == "" || allocation.ServerID == "" || allocation.State != domain.ServerAllocated || allocation.AllocatedAt.IsZero() {
 		return fmt.Errorf("invalid allocated match binding")
 	}
 	return RunSerializable(ctx, db, DefaultSerializableAttempts, func(ctx context.Context, tx *sql.Tx) error {
 		var participants, advanced int
-		if err := tx.QueryRowContext(ctx, BindAllocatedMatchParticipantsSQL, allocation.MatchID, allocation.AllocationID, allocation.ServerID).Scan(&participants, &advanced); err != nil {
+		var revision int64
+		if err := tx.QueryRowContext(ctx, BindAllocatedMatchParticipantsSQL, allocation.MatchID, allocation.AllocationID, allocation.ServerID).Scan(&participants, &advanced, &revision); err != nil {
 			return err
 		}
 		if participants == 0 || participants != advanced {
 			return domain.ErrConflict
 		}
-		return nil
+		rows, err := tx.QueryContext(ctx, serverRegistrationParticipantIDsSQL, allocation.MatchID)
+		if err != nil {
+			return err
+		}
+		playerIDs := make([]string, 0, participants)
+		for rows.Next() {
+			var playerID string
+			if err := rows.Scan(&playerID); err != nil {
+				rows.Close()
+				return err
+			}
+			playerIDs = append(playerIDs, playerID)
+		}
+		if err := rows.Err(); err != nil {
+			rows.Close()
+			return err
+		}
+		if err := rows.Close(); err != nil {
+			return err
+		}
+		payload, err := json.Marshal(map[string]any{
+			"event": "state_changed", "revision": revision, "resource_id": allocation.MatchID,
+			"occurred_at": allocation.AllocatedAt, "state": string(domain.Allocating), "match_id": allocation.MatchID, "player_ids": playerIDs,
+		})
+		if err != nil {
+			return err
+		}
+		_, err = tx.ExecContext(ctx, serverRegistrationOutboxSQL, fmt.Sprintf("match:%s:%d", allocation.MatchID, revision), allocation.MatchID, revision, payload)
+		return err
 	})
 }
 

server/store/allocation_match_sql_test.go

@@ -11,7 +11,7 @@ func TestAllocationMatchClaimSQLFencesConcurrentWorkers(t *testing.T) {
 	checks := map[string][]string{
 		ClaimAllocatingMatchSQL:                {"FOR UPDATE SKIP LOCKED", "allocation_id = 'allocation-' || candidate.match_id", "allocation_claimed_at <= $1", "ORDER BY created_at, match_id", "m.playlist"},
 		AllocatingMatchBuildSQL:                {"match_participants", "queue_tickets", "ORDER BY q.client_build"},
-		BindAllocatedMatchParticipantsSQL:      {"allocation_id = $2", "server_id IS NULL", "SET server_id = $3", "FROM allocations", "state = 'ALLOCATING'", "revision = revision + 1"},
+		BindAllocatedMatchParticipantsSQL:      {"allocation_id = $2", "server_id IS NULL", "SET server_id = $3", "FROM allocations", "state = 'ALLOCATING'", "revision = revision + 1", "SELECT revision FROM bound"},
 		ReleaseAllocatedMatchClaimSQL:          {"allocation_id = $2", "allocation_id = NULL", "allocation_claimed_at = NULL"},
 		AdvanceServerRegistrationSQL:           {"state = $4", "protocol_version = $7", "ASSIGNMENT_READY", "revision = revision + 1"},
 		ServerRegistrationIdempotencyInsertSQL: {"idempotency_keys", "ON CONFLICT (scope, idempotency_key) DO NOTHING", "payload_digest"},

server/store/postgres_integration_test.go

@@ -310,6 +310,14 @@ func TestPostgreSQLAllocationMatchClaimLeaseAndBindFence(t *testing.T) {
 	if err := db.QueryRowContext(ctx, `SELECT count(*) FROM queue_tickets WHERE ticket_id LIKE 'allocation-match-ticket-%' AND state = 'ALLOCATING'`).Scan(&allocatingTickets); err != nil || allocatingTickets != 2 {
 		t.Fatalf("allocating tickets=%d err=%v", allocatingTickets, err)
 	}
+	var eventType string
+	var eventPayload []byte
+	if err := db.QueryRowContext(ctx, `SELECT event_type, payload FROM outbox WHERE aggregate_id = 'allocation-match' AND event_type = 'state_changed'`).Scan(&eventType, &eventPayload); err != nil {
+		t.Fatalf("allocation outbox event: %v", err)
+	}
+	if eventType != "state_changed" || !strings.Contains(string(eventPayload), `"state":"ALLOCATING"`) || !strings.Contains(string(eventPayload), `"allocation-match-a"`) || !strings.Contains(string(eventPayload), `"allocation-match-b"`) {
+		t.Fatalf("allocation outbox event = %s", eventPayload)
+	}
 	if _, found, err := ClaimAllocatingMatch(ctx, db, "enet", now.Add(2*time.Second)); err != nil || found {
 		t.Fatalf("bound match re-claimed found=%t err=%v", found, err)
 	}