Defer world activation until welcome preflight confirmation

client/public/version.js

@@ -1,5 +1,5 @@
 // Maintainer-controlled web client version.
 // Format: YYYY.MM.DD Rn (example: 2026.02.20 R2)
-window.CHGRID_WEB_VERSION = "2026.03.01 R328";
+window.CHGRID_WEB_VERSION = "2026.03.01 R329";
 // Optional display timezone for timestamps. Falls back to America/Detroit if unset/invalid.
 window.CHGRID_TIME_ZONE = "America/Detroit";

client/src/main.ts

@@ -2091,6 +2091,7 @@ async function onSignalingMessage(message: IncomingMessage): Promise<void> {
   }
   await onAppMessage(message);
   if (message.type === 'welcome') {
+    signaling.send({ type: 'welcome_ready' });
     await setupMediaAfterAuth();
     if (playSelfLoginSound) {
       void audio.playSample(SYSTEM_SOUND_URLS.logon, 1);

client/src/network/protocol.ts

@@ -367,6 +367,7 @@ export type OutgoingMessage =
   | { type: 'auth_login'; username: string; password: string }
   | { type: 'auth_resume'; sessionToken: string }
   | { type: 'auth_logout' }
+  | { type: 'welcome_ready' }
   | { type: 'admin_roles_list' }
   | { type: 'admin_role_create'; name: string }
   | { type: 'admin_role_update_permissions'; role: string; permissions: string[] }

docs/protocol-notes.md

@@ -14,6 +14,7 @@ This is a behavior guide for packet semantics beyond raw schemas.
 - `auth_login`: authenticate with username/password.
 - `auth_resume`: resume prior session via stored session token.
 - `auth_logout`: revoke current session and disconnect.
+- `welcome_ready`: client confirms it accepted `welcome` preflight and is ready to join active roster.
 - `admin_roles_list`: request server role list (with user counts + permission sets).
 - `admin_role_create`: create role.
 - `admin_role_update_permissions`: replace one role permission set.
@@ -44,6 +45,7 @@ This is a behavior guide for packet semantics beyond raw schemas.
 - `admin_action_result`: structured result for admin actions.
   - admin mutations include `user_delete` for account deletion.
 - `welcome`: initial snapshot with users/items plus server UI/world metadata.
+  - Server delays roster activation/login broadcast until `welcome_ready` is received.
 - `signal`: forwarded WebRTC offer/answer/ICE.
 - `update_position`, `update_nickname`, `user_left`: presence updates.
 - `teleport_complete`: peer teleport landing event with spatial coordinates.

server/app/client.py

@@ -27,6 +27,7 @@ class ClientConnection:
     last_position_update_ms: int = 0
     movement_window_index: int = -1
     movement_window_steps_used: int = 0
+    world_ready: bool = False
 
     def summary(self) -> dict[str, str | int]:
         """Return a compact serializable snapshot for logs/diagnostics."""

server/app/models.py

@@ -63,6 +63,10 @@ class AuthLogoutPacket(BasePacket):
     type: Literal["auth_logout"]
 
 
+class WelcomeReadyPacket(BasePacket):
+    type: Literal["welcome_ready"]
+
+
 class AdminRolesListPacket(BasePacket):
     type: Literal["admin_roles_list"]
 
@@ -189,6 +193,7 @@ ClientPacket = (
     | AuthLoginPacket
     | AuthResumePacket
     | AuthLogoutPacket
+    | WelcomeReadyPacket
     | AdminRolesListPacket
     | AdminRoleCreatePacket
     | AdminRoleUpdatePermissionsPacket

server/app/server.py

@@ -102,6 +102,7 @@ from .models import (
     UpdateNicknamePacket,
     UpdatePositionPacket,
     UserLeftPacket,
+    WelcomeReadyPacket,
     WelcomePacket,
     WorldItem,
 )
@@ -1419,11 +1420,9 @@ class SignalingServer:
         )
         await self._send(client.websocket, packet)
 
-    async def _activate_authenticated_client(self, client: ClientConnection) -> None:
-        """Move an authenticated websocket client into the active world roster."""
+    async def _send_authenticated_welcome(self, client: ClientConnection) -> None:
+        """Prepare authenticated client state and send welcome before world activation."""
 
-        if client.websocket in self.clients:
-            return
         saved_x = getattr(client, "saved_x", None)
         saved_y = getattr(client, "saved_y", None)
         if isinstance(saved_x, int) and isinstance(saved_y, int) and self._is_in_bounds(saved_x, saved_y):
@@ -1437,6 +1436,16 @@ class SignalingServer:
         client.last_position_update_ms = now_ms
         client.movement_window_index = self._movement_window_index(now_ms)
         client.movement_window_steps_used = 0
+        client.world_ready = False
+        await self._send_welcome(client)
+
+    async def _activate_authenticated_client(self, client: ClientConnection) -> None:
+        """Move a welcomed authenticated client into active world roster."""
+
+        if client.websocket in self.clients:
+            client.world_ready = True
+            return
+        client.world_ready = True
         self.clients[client.websocket] = client
         LOGGER.info(
             "client authenticated id=%s user_id=%s username=%s total=%d",
@@ -1445,7 +1454,6 @@ class SignalingServer:
             client.username,
             len(self.clients),
         )
-        await self._send_welcome(client)
         await self._broadcast(
             BroadcastChatMessagePacket(
                 type="chat_message",
@@ -1617,7 +1625,7 @@ class SignalingServer:
                 authPolicy=self._auth_policy(),
             ),
         )
-        await self._activate_authenticated_client(client)
+        await self._send_authenticated_welcome(client)
         return True
 
     def _build_ui_definitions(self, client: ClientConnection | None = None) -> dict:
@@ -2082,6 +2090,14 @@ class SignalingServer:
             )
             return
 
+        if isinstance(packet, WelcomeReadyPacket):
+            await self._activate_authenticated_client(client)
+            return
+
+        if not client.world_ready:
+            PACKET_LOGGER.info("ignoring pre-ready packet id=%s type=%s", client.id, packet.type)
+            return
+
         if await self._handle_admin_packet(client, packet):
             return
 

server/tests/test_server_message_handling.py

@@ -276,6 +276,44 @@ async def test_auth_login_failure_message_is_generic(monkeypatch: pytest.MonkeyP
     assert auth_results[-1].message == AUTH_LOGIN_FAILURE_MESSAGE
 
 
+@pytest.mark.asyncio
+async def test_auth_login_defers_activation_until_welcome_ready(monkeypatch: pytest.MonkeyPatch) -> None:
+    server = SignalingServer("127.0.0.1", 8765, None, None)
+    username = f"ready_{uuid.uuid4().hex[:8]}"
+    server.auth_service.register(username, "password99")
+    ws = _fake_ws()
+    client = ClientConnection(websocket=ws, id="u1", nickname="tester")
+
+    send_payloads: list[object] = []
+    broadcast_payloads: list[object] = []
+
+    async def fake_send(websocket: ServerConnection, packet: object) -> None:
+        send_payloads.append(packet)
+
+    async def fake_broadcast(packet: object, exclude: ServerConnection | None = None) -> None:
+        broadcast_payloads.append(packet)
+
+    monkeypatch.setattr(server, "_send", fake_send)
+    monkeypatch.setattr(server, "_broadcast", fake_broadcast)
+
+    await server._handle_message(
+        client,
+        json.dumps({"type": "auth_login", "username": username, "password": "password99"}),
+    )
+
+    assert client.authenticated is True
+    assert client.world_ready is False
+    assert ws not in server.clients
+    assert any(getattr(packet, "type", "") == "welcome" for packet in send_payloads)
+    assert not any("has logged in" in getattr(packet, "message", "") for packet in broadcast_payloads)
+
+    await server._handle_message(client, json.dumps({"type": "welcome_ready"}))
+
+    assert client.world_ready is True
+    assert server.clients.get(ws) is client
+    assert any("has logged in" in getattr(packet, "message", "") for packet in broadcast_payloads)
+
+
 @pytest.mark.asyncio
 async def test_auth_resume_failure_message_is_generic(monkeypatch: pytest.MonkeyPatch) -> None:
     server = SignalingServer("127.0.0.1", 8765, None, None)