feat(multiplayer): wire allocated fleet runtime

server/supervisor/supervisor.go

@@ -182,10 +182,12 @@ func (s *Supervisor) Start(ctx context.Context) error {
 		if s.config.Transport == "steam_sdr" {
 			env = append(env, "SDR_LISTEN_PORT="+strconv.Itoa(port), "SDR_IP="+address+":"+strconv.Itoa(port))
 		}
-		if err := s.fetchRoster(ctx); err != nil {
+		rosterExpiry, err := s.fetchRoster(ctx)
+		if err != nil {
 			return err
 		}
-		command := withPort(s.config.Command, port)
+		command := withAllocatedConfig(s.config.Command, s.matchID(), s.config.ServerID, s.config.ImageDigest, rosterExpiry)
+		command = withPort(command, port)
 		s.cmd = exec.CommandContext(ctx, command[0], command[1:]...)
 	} else {
 		s.cmd = exec.CommandContext(ctx, s.config.Command[0], s.config.Command[1:]...)
@@ -218,68 +220,112 @@ func (s *Supervisor) Start(ctx context.Context) error {
 	return nil
 }
 
-func (s *Supervisor) fetchRoster(ctx context.Context) error {
+func (s *Supervisor) fetchRoster(ctx context.Context) (time.Time, error) {
 	if s.config.RosterPath == "" {
-		return nil
+		return time.Time{}, nil
 	}
 	matchID := s.matchID()
 	if matchID == "" {
-		return fmt.Errorf("roster fetch has no match ID")
+		return time.Time{}, fmt.Errorf("roster fetch has no match ID")
 	}
 	token, err := s.workloadToken()
 	if err != nil {
-		return err
+		return time.Time{}, err
 	}
 	rosterURL := strings.TrimRight(s.config.ControlPlaneURL, "/") + "/v1/servers/" + url.PathEscape(s.config.ServerID) + "/roster"
 	request, err := http.NewRequestWithContext(ctx, http.MethodGet, rosterURL, nil)
 	if err != nil {
-		return err
+		return time.Time{}, err
 	}
 	request.Header.Set("Authorization", "Bearer "+token)
 	response, err := s.client.Do(request)
 	if err != nil {
-		return err
+		return time.Time{}, err
 	}
 	defer response.Body.Close()
 	if response.StatusCode/100 != 2 {
-		return fmt.Errorf("control-plane roster returned %s", response.Status)
+		return time.Time{}, fmt.Errorf("control-plane roster returned %s", response.Status)
 	}
 	var roster []json.RawMessage
 	if err := json.NewDecoder(io.LimitReader(response.Body, 1<<20)).Decode(&roster); err != nil || len(roster) == 0 {
 		if err == nil {
 			err = fmt.Errorf("empty roster")
 		}
-		return fmt.Errorf("decode control-plane roster: %w", err)
+		return time.Time{}, fmt.Errorf("decode control-plane roster: %w", err)
 	}
+	var expiry time.Time
 	for _, envelope := range roster {
 		if len(envelope) == 0 || string(envelope) == "null" {
-			return fmt.Errorf("control-plane roster contains an invalid envelope")
+			return time.Time{}, fmt.Errorf("control-plane roster contains an invalid envelope")
+		}
+		var decoded struct {
+			Authorisation struct {
+				ExpiresAt time.Time `json:"expires_at"`
+			} `json:"authorisation"`
+		}
+		if err := json.Unmarshal(envelope, &decoded); err != nil || decoded.Authorisation.ExpiresAt.IsZero() {
+			return time.Time{}, fmt.Errorf("control-plane roster contains an envelope without expiry")
+		}
+		if expiry.IsZero() || decoded.Authorisation.ExpiresAt.Before(expiry) {
+			expiry = decoded.Authorisation.ExpiresAt
 		}
 	}
 	contents, err := json.Marshal(roster)
 	if err != nil {
-		return fmt.Errorf("encode roster: %w", err)
+		return time.Time{}, fmt.Errorf("encode roster: %w", err)
 	}
 	directory := filepath.Dir(s.config.RosterPath)
 	temporary, err := os.CreateTemp(directory, ".cosmic-clash-roster-*")
 	if err != nil {
-		return fmt.Errorf("create roster file: %w", err)
+		return time.Time{}, fmt.Errorf("create roster file: %w", err)
 	}
 	temporaryName := temporary.Name()
 	defer os.Remove(temporaryName)
-	if err := temporary.Chmod(0600); err == nil {
-		_, err = temporary.Write(contents)
+	if err := temporary.Chmod(0600); err != nil {
+		_ = temporary.Close()
+		return time.Time{}, fmt.Errorf("secure roster file: %w", err)
 	}
+	_, err = temporary.Write(contents)
 	if closeErr := temporary.Close(); err == nil {
 		err = closeErr
 	}
 	if err != nil {
-		return fmt.Errorf("write roster file: %w", err)
+		return time.Time{}, fmt.Errorf("write roster file: %w", err)
 	}
 	if err := os.Rename(temporaryName, s.config.RosterPath); err != nil {
-		return fmt.Errorf("install roster file: %w", err)
+		return time.Time{}, fmt.Errorf("install roster file: %w", err)
 	}
-	return nil
+	return expiry, nil
+}
+
+func withAllocatedConfig(command []string, matchID, serverID, imageDigest string, rosterExpiry time.Time) []string {
+	result := append([]string(nil), command...)
+	values := map[string]string{
+		"match-id":            matchID,
+		"server-id":           serverID,
+		"server-image-digest": imageDigest,
+	}
+	if !rosterExpiry.IsZero() {
+		values["assignment-expiry-unix"] = strconv.FormatInt(rosterExpiry.Unix(), 10)
+	}
+	for key, value := range values {
+		if value == "" {
+			continue
+		}
+		prefix := "--" + key + "="
+		replaced := false
+		for i, arg := range result {
+			if strings.HasPrefix(arg, prefix) {
+				result[i] = prefix + value
+				replaced = true
+				break
+			}
+		}
+		if !replaced {
+			result = append(result, prefix+value)
+		}
+	}
+	return result
 }
 
 // reportAssignmentReady is best-effort: process-ready has already succeeded,

server/supervisor/supervisor_integration_test.go

@@ -80,7 +80,7 @@ func TestRealSupervisorRegistersAllocatedServerThroughControlPlane(t *testing.T)
 		if err := store.SaveAssignment(ctx, db, store.DurableAssignment{
 			MatchID: "supervisor-live-match", PlayerID: player, AllocationID: request.AllocationID, ServerID: "supervisor-live-server", Slot: index,
 			Region: "EU", ClientBuild: "build-1", ProtocolVersion: 1, Transport: "enet", Endpoint: "127.0.0.1:7777",
-			JoinAuthorisation: base64.RawURLEncoding.EncodeToString([]byte(fmt.Sprintf(`{"authorisation":{"match_id":"supervisor-live-match","server_id":"supervisor-live-server","player_id":%q},"signature":"sig"}`, player))), ManifestDigest: []byte{0, 1, 2, 3}, ExpiresAt: now.Add(time.Hour), Revision: 1,
+			JoinAuthorisation: base64.RawURLEncoding.EncodeToString([]byte(fmt.Sprintf(`{"authorisation":{"match_id":"supervisor-live-match","server_id":"supervisor-live-server","player_id":%q,"expires_at":%q},"signature":"sig"}`, player, now.Add(time.Hour).Format(time.RFC3339)))), ManifestDigest: []byte{0, 1, 2, 3}, ExpiresAt: now.Add(time.Hour), Revision: 1,
 		}); err != nil {
 			t.Fatal(err)
 		}

server/supervisor/supervisor_test.go

@@ -87,7 +87,7 @@ func TestAllocatedStartMaterializesWorkloadAuthenticatedRosterBeforeChild(t *tes
 				w.WriteHeader(http.StatusUnauthorized)
 				return
 			}
-			_, _ = w.Write([]byte(`[{"authorisation":{"player_id":"player-1"},"signature":"sig"}]`))
+			_, _ = w.Write([]byte(`[{"authorisation":{"player_id":"player-1","expires_at":"2030-01-01T00:00:00Z"},"signature":"sig"}]`))
 			return
 		}
 		if r.URL.Path == "/v1/servers/server-1/register" {