进房接口

api/proto/room/v1/room.proto

@@ -526,6 +526,8 @@ message RoomSnapshot {
   RoomRocketState rocket = 20;
   // ban_states 保存 ban 的过期边界；ban_user_ids 仍只服务简单集合判断。
   repeated RoomBanState ban_states = 21;
+  // online_count 允许 lite 响应不携带 online_users 明细仍保留准确在线人数。
+  int32 online_count = 22;
 }
 
 // RoomBackgroundImage 是房间维度保存过的背景图素材。
@@ -656,6 +658,8 @@ message JoinRoomRequest {
   bool actor_is_robot = 7;
   // actor_display_profile 是进房用户展示资料快照，room-service 只透传到进房 IM/outbox，不写入 RoomState。
   RoomUserDisplayProfile actor_display_profile = 8;
+  // response_mode=lite 只裁剪响应快照，不改变 Room Cell 命令提交、outbox 或 IM 事件语义。
+  string response_mode = 9;
 }
 
 // JoinRoomResponse 返回加入后的房间快照。

api/proto/user/v1/user.proto

@@ -691,6 +691,25 @@ message BatchGetUsersResponse {
   map<int64, User> users = 1;
 }
 
+// RoomBasicUser 是房间首屏只需要的用户展示基础资料。
+message RoomBasicUser {
+  int64 user_id = 1;
+  string username = 2;
+  string avatar = 3;
+  string display_user_id = 4;
+}
+
+// BatchGetRoomBasicUsersRequest 为房间进房 lite 首屏批量读取最小用户资料。
+message BatchGetRoomBasicUsersRequest {
+  RequestMeta meta = 1;
+  repeated int64 user_ids = 2;
+}
+
+// BatchGetRoomBasicUsersResponse 返回按 user_id 索引的房间首屏基础资料。
+message BatchGetRoomBasicUsersResponse {
+  map<int64, RoomBasicUser> users = 1;
+}
+
 // ListUserIDsRequest 给低频后台 fanout/重算任务按 user_id 游标读取目标用户。
 message ListUserIDsRequest {
   RequestMeta meta = 1;
@@ -1324,6 +1343,7 @@ service UserService {
   rpc BusinessUserLookup(BusinessUserLookupRequest) returns (BusinessUserLookupResponse);
   rpc GetMyProfileStats(GetMyProfileStatsRequest) returns (GetMyProfileStatsResponse);
   rpc BatchGetUsers(BatchGetUsersRequest) returns (BatchGetUsersResponse);
+  rpc BatchGetRoomBasicUsers(BatchGetRoomBasicUsersRequest) returns (BatchGetRoomBasicUsersResponse);
   rpc ListUserIDs(ListUserIDsRequest) returns (ListUserIDsResponse);
   rpc GetUserMicLifetimeStats(GetUserMicLifetimeStatsRequest) returns (GetUserMicLifetimeStatsResponse);
   rpc UpdateUserProfile(UpdateUserProfileRequest) returns (UpdateUserProfileResponse);

api/proto/user/v1/user_grpc.pb.go

@@ -24,6 +24,7 @@ const (
 	UserService_BusinessUserLookup_FullMethodName          = "/hyapp.user.v1.UserService/BusinessUserLookup"
 	UserService_GetMyProfileStats_FullMethodName           = "/hyapp.user.v1.UserService/GetMyProfileStats"
 	UserService_BatchGetUsers_FullMethodName               = "/hyapp.user.v1.UserService/BatchGetUsers"
+	UserService_BatchGetRoomBasicUsers_FullMethodName      = "/hyapp.user.v1.UserService/BatchGetRoomBasicUsers"
 	UserService_ListUserIDs_FullMethodName                 = "/hyapp.user.v1.UserService/ListUserIDs"
 	UserService_GetUserMicLifetimeStats_FullMethodName     = "/hyapp.user.v1.UserService/GetUserMicLifetimeStats"
 	UserService_UpdateUserProfile_FullMethodName           = "/hyapp.user.v1.UserService/UpdateUserProfile"
@@ -52,6 +53,7 @@ type UserServiceClient interface {
 	BusinessUserLookup(ctx context.Context, in *BusinessUserLookupRequest, opts ...grpc.CallOption) (*BusinessUserLookupResponse, error)
 	GetMyProfileStats(ctx context.Context, in *GetMyProfileStatsRequest, opts ...grpc.CallOption) (*GetMyProfileStatsResponse, error)
 	BatchGetUsers(ctx context.Context, in *BatchGetUsersRequest, opts ...grpc.CallOption) (*BatchGetUsersResponse, error)
+	BatchGetRoomBasicUsers(ctx context.Context, in *BatchGetRoomBasicUsersRequest, opts ...grpc.CallOption) (*BatchGetRoomBasicUsersResponse, error)
 	ListUserIDs(ctx context.Context, in *ListUserIDsRequest, opts ...grpc.CallOption) (*ListUserIDsResponse, error)
 	GetUserMicLifetimeStats(ctx context.Context, in *GetUserMicLifetimeStatsRequest, opts ...grpc.CallOption) (*GetUserMicLifetimeStatsResponse, error)
 	UpdateUserProfile(ctx context.Context, in *UpdateUserProfileRequest, opts ...grpc.CallOption) (*UpdateUserProfileResponse, error)
@@ -127,6 +129,16 @@ func (c *userServiceClient) BatchGetUsers(ctx context.Context, in *BatchGetUsers
 	return out, nil
 }
 
+func (c *userServiceClient) BatchGetRoomBasicUsers(ctx context.Context, in *BatchGetRoomBasicUsersRequest, opts ...grpc.CallOption) (*BatchGetRoomBasicUsersResponse, error) {
+	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
+	out := new(BatchGetRoomBasicUsersResponse)
+	err := c.cc.Invoke(ctx, UserService_BatchGetRoomBasicUsers_FullMethodName, in, out, cOpts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
 func (c *userServiceClient) ListUserIDs(ctx context.Context, in *ListUserIDsRequest, opts ...grpc.CallOption) (*ListUserIDsResponse, error) {
 	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
 	out := new(ListUserIDsResponse)
@@ -288,6 +300,7 @@ type UserServiceServer interface {
 	BusinessUserLookup(context.Context, *BusinessUserLookupRequest) (*BusinessUserLookupResponse, error)
 	GetMyProfileStats(context.Context, *GetMyProfileStatsRequest) (*GetMyProfileStatsResponse, error)
 	BatchGetUsers(context.Context, *BatchGetUsersRequest) (*BatchGetUsersResponse, error)
+	BatchGetRoomBasicUsers(context.Context, *BatchGetRoomBasicUsersRequest) (*BatchGetRoomBasicUsersResponse, error)
 	ListUserIDs(context.Context, *ListUserIDsRequest) (*ListUserIDsResponse, error)
 	GetUserMicLifetimeStats(context.Context, *GetUserMicLifetimeStatsRequest) (*GetUserMicLifetimeStatsResponse, error)
 	UpdateUserProfile(context.Context, *UpdateUserProfileRequest) (*UpdateUserProfileResponse, error)
@@ -328,6 +341,9 @@ func (UnimplementedUserServiceServer) GetMyProfileStats(context.Context, *GetMyP
 func (UnimplementedUserServiceServer) BatchGetUsers(context.Context, *BatchGetUsersRequest) (*BatchGetUsersResponse, error) {
 	return nil, status.Errorf(codes.Unimplemented, "method BatchGetUsers not implemented")
 }
+func (UnimplementedUserServiceServer) BatchGetRoomBasicUsers(context.Context, *BatchGetRoomBasicUsersRequest) (*BatchGetRoomBasicUsersResponse, error) {
+	return nil, status.Errorf(codes.Unimplemented, "method BatchGetRoomBasicUsers not implemented")
+}
 func (UnimplementedUserServiceServer) ListUserIDs(context.Context, *ListUserIDsRequest) (*ListUserIDsResponse, error) {
 	return nil, status.Errorf(codes.Unimplemented, "method ListUserIDs not implemented")
 }
@@ -484,6 +500,24 @@ func _UserService_BatchGetUsers_Handler(srv interface{}, ctx context.Context, de
 	return interceptor(ctx, in, info, handler)
 }
 
+func _UserService_BatchGetRoomBasicUsers_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(BatchGetRoomBasicUsersRequest)
+	if err := dec(in); err != nil {
+		return nil, err
+	}
+	if interceptor == nil {
+		return srv.(UserServiceServer).BatchGetRoomBasicUsers(ctx, in)
+	}
+	info := &grpc.UnaryServerInfo{
+		Server:     srv,
+		FullMethod: UserService_BatchGetRoomBasicUsers_FullMethodName,
+	}
+	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
+		return srv.(UserServiceServer).BatchGetRoomBasicUsers(ctx, req.(*BatchGetRoomBasicUsersRequest))
+	}
+	return interceptor(ctx, in, info, handler)
+}
+
 func _UserService_ListUserIDs_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
 	in := new(ListUserIDsRequest)
 	if err := dec(in); err != nil {
@@ -781,6 +815,10 @@ var UserService_ServiceDesc = grpc.ServiceDesc{
 			MethodName: "BatchGetUsers",
 			Handler:    _UserService_BatchGetUsers_Handler,
 		},
+		{
+			MethodName: "BatchGetRoomBasicUsers",
+			Handler:    _UserService_BatchGetRoomBasicUsers_Handler,
+		},
 		{
 			MethodName: "ListUserIDs",
 			Handler:    _UserService_ListUserIDs_Handler,

docs/flutter对接/进房接口Flutter对接.md

@@ -0,0 +1,282 @@
+# 进房接口 Flutter 对接
+
+## 接口地址
+
+```http
+POST /api/v1/rooms/join
+Authorization: Bearer <access_token>
+Content-Type: application/json
+```
+
+新版本进房默认使用 `response_mode=lite`。`full` 仍保留给旧客户端兼容，不建议新 Flutter 首屏使用。
+
+## 参数
+
+Body：
+
+| 字段 | 类型 | 必填 | 说明 |
+| --- | --- | --- | --- |
+| `room_id` | string | 是 | 房间 ID。 |
+| `command_id` | string | 是 | 本次进房命令 ID。同一次点击超时重试复用同一个值，下一次重新进房换新值。 |
+| `role` | string | 否 | 不传默认 `audience`。房主身份由服务端按房间 owner 判断，客户端不要靠传 `owner` 获取权限。 |
+| `password` | string | 否 | 密码房传房间密码，非密码房不传或传空。 |
+| `response_mode` | string | 是 | 新版固定传 `lite`。可选值：`lite` / `full`。 |
+
+请求示例：
+
+```json
+{
+  "room_id": "lalu_abc123",
+  "command_id": "cmd_join_room_lalu_abc123_10001_1778000001000",
+  "role": "audience",
+  "password": "",
+  "response_mode": "lite"
+}
+```
+
+也支持 query 参数：
+
+```http
+POST /api/v1/rooms/join?response_mode=lite
+```
+
+Flutter 建议放在 body 里，避免调用层漏拼 query。
+
+## 返回值
+
+统一外壳：
+
+```json
+{
+  "code": "OK",
+  "message": "ok",
+  "request_id": "req_xxx",
+  "data": {}
+}
+```
+
+成功返回示例：
+
+```json
+{
+  "code": "OK",
+  "message": "ok",
+  "request_id": "req_xxx",
+  "data": {
+    "result": {
+      "applied": true,
+      "room_version": 8,
+      "server_time_ms": 1778000001123
+    },
+    "room": {
+      "room_id": "lalu_abc123",
+      "im_group_id": "lalu_abc123",
+      "room_short_id": "10001",
+      "title": "Live Room",
+      "cover_url": "https://cdn.example/room.png",
+      "background_url": "https://cdn.example/bg.png",
+      "description": "welcome",
+      "owner_user_id": "10001",
+      "mode": "voice",
+      "status": "active",
+      "chat_enabled": true,
+      "locked": false,
+      "heat": 88,
+      "online_count": 200,
+      "seat_count": 10,
+      "occupied_seat_count": 2,
+      "visible_region_id": 1001,
+      "version": 8
+    },
+    "viewer": {
+      "user_id": "10001",
+      "role": "audience",
+      "joined_at_ms": 1778000001000,
+      "last_seen_at_ms": 1778000001100
+    },
+    "seats": [
+      {
+        "seat_no": 1,
+        "user_id": "10002",
+        "locked": false,
+        "publish_state": "publishing",
+        "mic_session_id": "mic_10002",
+        "publish_deadline_ms": 1778000030000,
+        "mic_muted": false,
+        "seat_status": "publishing",
+        "mic_heartbeat_at_ms": 1778000000000,
+        "gift_value": 0
+      },
+      {
+        "seat_no": 2,
+        "locked": false,
+        "mic_muted": false,
+        "gift_value": 0
+      }
+    ],
+    "profiles": [
+      {
+        "user_id": "10001",
+        "username": "host",
+        "avatar": "https://cdn.example/avatar.png",
+        "display_user_id": "10001"
+      },
+      {
+        "user_id": "10002",
+        "username": "speaker",
+        "avatar": "https://cdn.example/avatar2.png",
+        "display_user_id": "10002"
+      }
+    ],
+    "im": {
+      "group_id": "lalu_abc123",
+      "need_join_group": true
+    },
+    "rtc": {
+      "need_token": true,
+      "available": true,
+      "token": {
+        "sdk_app_id": 1400000000,
+        "user_id": "10001",
+        "rtc_user_id": "10001",
+        "user_sig": "xxx",
+        "expire_at_ms": 1778007200000,
+        "room_id": "lalu_abc123",
+        "rtc_room_id": "lalu_abc123",
+        "rtc_room_id_type": "string",
+        "str_room_id": "lalu_abc123",
+        "app_scene": "voice_chat_room",
+        "role": "user"
+      }
+    },
+    "server_time_ms": 1778000001123
+  }
+}
+```
+
+字段说明：
+
+| 字段 | 说明 |
+| --- | --- |
+| `data.result.applied` | 本次进房是否真正写入。重复 `command_id` 重试可能为 `false`。 |
+| `data.result.room_version` | 房间版本，用于客户端状态更新判断。 |
+| `data.room.room_id` | 房间 ID。 |
+| `data.room.im_group_id` | 腾讯 IM 房间群 ID。当前通常等于 `room_id`，客户端仍以返回值为准。 |
+| `data.room.online_count` | 房间在线人数。`lite` 不返回在线用户明细，只返回人数。 |
+| `data.room.seat_count` | 麦位总数。 |
+| `data.room.occupied_seat_count` | 已占用麦位数。 |
+| `data.viewer` | 当前登录用户在房间内的 presence。 |
+| `data.viewer.role` | 当前用户房间角色，房主会由服务端返回 `owner`。 |
+| `data.seats` | 首屏麦位状态。 |
+| `data.seats[].user_id` | 麦上用户 ID；空麦不返回该字段。 |
+| `data.seats[].publish_state` | 麦上发流状态，常见值：`pending_publish` / `publishing`。 |
+| `data.seats[].mic_session_id` | 麦位发流会话 ID。麦上心跳、发流确认需要使用它。 |
+| `data.seats[].seat_status` | 麦位展示状态，常见值：`empty` / `locked` / `occupied` / `publishing` / `muted`。 |
+| `data.profiles` | 首屏基础资料，只包含房主、当前用户、麦上用户。 |
+| `data.profiles[].username` | 昵称。 |
+| `data.profiles[].avatar` | 头像。 |
+| `data.profiles[].display_user_id` | 展示 ID。 |
+| `data.im.group_id` | Flutter 调腾讯 IM `joinGroup` 使用的群 ID。 |
+| `data.im.need_join_group` | 为 `true` 时需要加入腾讯 IM 群。 |
+| `data.rtc.available` | 是否拿到 RTC 票据。 |
+| `data.rtc.token` | RTC 进房票据。`available=false` 时可能为空。 |
+| `data.rtc.reason` | RTC 不可用原因。业务进房成功时，RTC 不可用不代表进房失败。 |
+| `data.server_time_ms` | 服务端时间，UTC epoch milliseconds。 |
+
+`lite` 不返回这些内容：
+
+| 字段 | 说明 |
+| --- | --- |
+| `contribution_rank` | 贡献榜不在进房首屏主包返回。 |
+| `profiles[].avatar_frame` | 头像框后置拉。 |
+| `profiles[].profile_card` | 资料卡后置拉。 |
+| `profiles[].vehicle` | 座驾后置拉。 |
+| `profiles[].mic_seat_animation` | 麦位动画后置拉。 |
+| `profiles[].badges` | 等级/成就徽章后置拉。 |
+| `profiles[].vip` | VIP 展示后置拉。 |
+
+## 相关 IM
+
+进房成功后 Flutter 执行：
+
+```text
+1. POST /api/v1/rooms/join，body 传 response_mode=lite
+2. 如果 data.im.need_join_group=true，调用腾讯 IM joinGroup(data.im.group_id)
+3. joinGroup 成功或已在群内，都按进房 IM 成功处理
+4. 页面开始房间 heartbeat
+5. 如果 data.rtc.available=true，用 data.rtc.token 进入 RTC
+```
+
+说明：
+
+| 项 | 说明 |
+| --- | --- |
+| IM 登录 | 进房接口不返回 IM UserSig。Flutter 仍然通过 `GET /api/v1/im/usersig` 获取并登录腾讯 IM。 |
+| IM 入群 | 必须先 `JoinRoom` 成功，再调腾讯 IM `joinGroup`。不要先入 IM 群。 |
+| 入房广播 | 服务端会发 `RoomUserJoined` 房间事件。Flutter 按现有房间 IM 事件逻辑展示入房飘窗。 |
+| 重复进房 | 用户重新打开房间页或重连时，服务端仍会给展示用入房事件，Flutter 正常展示即可。 |
+| 入场座驾 | `lite` 进房不携带座驾快照。座驾、头像框、资料卡、麦位动画等展示资料在进房 UI 出来后异步补齐。 |
+
+## 后置资料接口
+
+进房首屏出来后，再按需要异步拉展示资料：
+
+```http
+GET /api/v1/users/room-display-profiles:batch?user_ids=10001,10002
+Authorization: Bearer <access_token>
+```
+
+参数：
+
+| 字段 | 类型 | 必填 | 说明 |
+| --- | --- | --- | --- |
+| `user_ids` | string | 是 | 逗号分隔的用户 ID。也支持多个 `user_id=10001&user_id=10002`。 |
+
+返回值：
+
+```json
+{
+  "code": "OK",
+  "message": "ok",
+  "request_id": "req_xxx",
+  "data": {
+    "profiles": [
+      {
+        "user_id": "10001",
+        "username": "host",
+        "avatar": "https://cdn.example/avatar.png",
+        "display_user_id": "10001",
+        "avatar_frame": {},
+        "profile_card": {},
+        "vehicle": {},
+        "mic_seat_animation": {},
+        "badges": [],
+        "vip": {},
+        "level": {},
+        "level_badges": {},
+        "charm": 0
+      }
+    ]
+  }
+}
+```
+
+当前用户自己的装扮也可以后置拉：
+
+```http
+GET /api/v1/appearance
+GET /api/v1/users/me/appearance
+```
+
+## 常见错误
+
+| code | HTTP | 说明 |
+| --- | --- | --- |
+| `INVALID_JSON` | 400 | 请求体不是合法 JSON。 |
+| `INVALID_ARGUMENT` | 400 | 参数错误，例如 `response_mode` 不是 `lite` 或 `full`。 |
+| `UNAUTHORIZED` | 401 | 未登录或 token 无效。 |
+| `PROFILE_REQUIRED` | 403 | 用户资料未补全。 |
+| `PERMISSION_DENIED` | 403 | 密码错误、被踢/被禁等权限问题。 |
+| `ROOM_CLOSED` | 409 | 房间已关闭；非房主不能进入。 |
+| `NOT_FOUND` | 404 | 房间不存在。 |
+| `UPSTREAM_ERROR` | 502 | 上游服务异常。 |

services/gateway-service/internal/client/user_client.go

@@ -39,6 +39,7 @@ type UserProfileClient interface {
 	BusinessUserLookup(ctx context.Context, req *userv1.BusinessUserLookupRequest) (*userv1.BusinessUserLookupResponse, error)
 	GetMyProfileStats(ctx context.Context, req *userv1.GetMyProfileStatsRequest) (*userv1.GetMyProfileStatsResponse, error)
 	BatchGetUsers(ctx context.Context, req *userv1.BatchGetUsersRequest) (*userv1.BatchGetUsersResponse, error)
+	BatchGetRoomBasicUsers(ctx context.Context, req *userv1.BatchGetRoomBasicUsersRequest) (*userv1.BatchGetRoomBasicUsersResponse, error)
 	CompleteOnboarding(ctx context.Context, req *userv1.CompleteOnboardingRequest) (*userv1.CompleteOnboardingResponse, error)
 	UpdateUserProfile(ctx context.Context, req *userv1.UpdateUserProfileRequest) (*userv1.UpdateUserProfileResponse, error)
 	UpdateUserProfileBackground(ctx context.Context, req *userv1.UpdateUserProfileBackgroundRequest) (*userv1.UpdateUserProfileBackgroundResponse, error)
@@ -355,6 +356,10 @@ func (c *grpcUserProfileClient) BatchGetUsers(ctx context.Context, req *userv1.B
 	return c.client.BatchGetUsers(ctx, req)
 }
 
+func (c *grpcUserProfileClient) BatchGetRoomBasicUsers(ctx context.Context, req *userv1.BatchGetRoomBasicUsersRequest) (*userv1.BatchGetRoomBasicUsersResponse, error) {
+	return c.client.BatchGetRoomBasicUsers(ctx, req)
+}
+
 func (c *grpcUserProfileClient) CompleteOnboarding(ctx context.Context, req *userv1.CompleteOnboardingRequest) (*userv1.CompleteOnboardingResponse, error) {
 	return c.client.CompleteOnboarding(ctx, req)
 }

services/gateway-service/internal/transport/http/activityapi/invite_activity_reward_handler_test.go

@@ -113,6 +113,10 @@ func (f *fakeInviteActivityUserProfileClient) BatchGetUsers(_ context.Context, r
 	return &userv1.BatchGetUsersResponse{Users: f.users}, nil
 }
 
+func (f *fakeInviteActivityUserProfileClient) BatchGetRoomBasicUsers(context.Context, *userv1.BatchGetRoomBasicUsersRequest) (*userv1.BatchGetRoomBasicUsersResponse, error) {
+	return &userv1.BatchGetRoomBasicUsersResponse{}, nil
+}
+
 func (f *fakeInviteActivityUserProfileClient) GetUser(context.Context, *userv1.GetUserRequest) (*userv1.GetUserResponse, error) {
 	return &userv1.GetUserResponse{}, nil
 }

services/gateway-service/internal/transport/http/response_test.go

@@ -318,6 +318,8 @@ type fakeUserProfileClient struct {
 	lastStats           *userv1.GetMyProfileStatsRequest
 	lastBatch           *userv1.BatchGetUsersRequest
 	batchRequests       []*userv1.BatchGetUsersRequest
+	lastRoomBasicBatch  *userv1.BatchGetRoomBasicUsersRequest
+	roomBasicRequests   []*userv1.BatchGetRoomBasicUsersRequest
 	getRequests         []*userv1.GetUserRequest
 	lastComplete        *userv1.CompleteOnboardingRequest
 	lastUpdate          *userv1.UpdateUserProfileRequest
@@ -958,6 +960,32 @@ func (f *fakeUserProfileClient) BatchGetUsers(_ context.Context, req *userv1.Bat
 	return &userv1.BatchGetUsersResponse{Users: users}, nil
 }
 
+func (f *fakeUserProfileClient) BatchGetRoomBasicUsers(_ context.Context, req *userv1.BatchGetRoomBasicUsersRequest) (*userv1.BatchGetRoomBasicUsersResponse, error) {
+	f.lastRoomBasicBatch = req
+	f.roomBasicRequests = append(f.roomBasicRequests, req)
+	users := make(map[int64]*userv1.RoomBasicUser, len(req.GetUserIds()))
+	for _, userID := range req.GetUserIds() {
+		if f.usersByID != nil {
+			if user, ok := f.usersByID[userID]; ok {
+				users[userID] = &userv1.RoomBasicUser{
+					UserId:        user.GetUserId(),
+					Username:      user.GetUsername(),
+					Avatar:        user.GetAvatar(),
+					DisplayUserId: user.GetDisplayUserId(),
+				}
+				continue
+			}
+		}
+		users[userID] = &userv1.RoomBasicUser{
+			UserId:        userID,
+			Username:      "user-" + strconv.FormatInt(userID, 10),
+			Avatar:        "https://cdn.example/avatar.png",
+			DisplayUserId: strconv.FormatInt(100000+userID, 10),
+		}
+	}
+	return &userv1.BatchGetRoomBasicUsersResponse{Users: users}, nil
+}
+
 func (f *fakeUserProfileClient) CompleteOnboarding(_ context.Context, req *userv1.CompleteOnboardingRequest) (*userv1.CompleteOnboardingResponse, error) {
 	f.lastComplete = req
 	if f.completeErr != nil {
@@ -3290,6 +3318,96 @@ func TestJoinRoomReturnsInitialDataWithIMGroupRTCTokenAndProfiles(t *testing.T)
 	}
 }
 
+func TestJoinRoomLiteReturnsFirstScreenFieldsWithoutDisplayHydration(t *testing.T) {
+	roomClient := &fakeRoomClient{joinResp: &roomv1.JoinRoomResponse{
+		Result: &roomv1.CommandResult{Applied: true, RoomVersion: 8, ServerTimeMs: 1_700_000_010_123},
+		User:   &roomv1.RoomUser{UserId: 42, Role: "audience", JoinedAtMs: 1_700_000_010_000, LastSeenAtMs: 1_700_000_010_100},
+		Room: &roomv1.RoomSnapshot{
+			RoomId:      "room_lite",
+			OwnerUserId: 101,
+			Mode:        "voice",
+			Status:      "active",
+			ChatEnabled: true,
+			MicSeats:    []*roomv1.SeatState{{SeatNo: 1, UserId: 102, PublishState: "publishing"}, {SeatNo: 2, Locked: true}},
+			GiftRank:    []*roomv1.RankItem{{UserId: 301, Score: 900, GiftValue: 900}},
+			RoomExt:     map[string]string{"title": "Lite Room", "cover_url": "https://cdn.example/lite.png"},
+			Heat:        88,
+			Version:     8,
+			RoomShortId: "100102",
+			OnlineCount: 200,
+			Locked:      true,
+		},
+	}}
+	walletClient := &fakeWalletClient{batchEquippedResp: &walletv1.BatchGetUserEquippedResourcesResponse{}}
+	profileClient := &fakeUserProfileClient{}
+	handler := NewHandlerWithConfig(roomClient, nil, nil, nil, TencentIMConfig{}, profileClient)
+	handler.SetWalletClient(walletClient)
+	handler.SetTencentRTC(TencentRTCConfig{
+		Enabled:    true,
+		SDKAppID:   1400000000,
+		SecretKey:  "secret",
+		UserSigTTL: 2 * time.Hour,
+		RoomIDType: "string",
+		AppScene:   "voice_chat_room",
+	})
+	router := handler.Routes(auth.NewVerifier("secret"))
+	request := httptest.NewRequest(http.MethodPost, "/api/v1/rooms/join", bytes.NewReader([]byte(`{"room_id":"room_lite","command_id":"cmd-join-lite","role":"audience","response_mode":"lite"}`)))
+	request.Header.Set("Authorization", "Bearer "+signGatewayToken(t, "secret", 42))
+	request.Header.Set("X-Request-ID", "req-join-lite")
+	recorder := httptest.NewRecorder()
+
+	router.ServeHTTP(recorder, request)
+
+	if recorder.Code != http.StatusOK {
+		t.Fatalf("status mismatch: got %d body=%s", recorder.Code, recorder.Body.String())
+	}
+	if roomClient.lastJoin == nil || roomClient.lastJoin.GetResponseMode() != "lite" || roomClient.lastJoin.GetEntryVehicle() != nil {
+		t.Fatalf("lite join must pass response_mode and skip entry vehicle: %+v", roomClient.lastJoin)
+	}
+	if len(walletClient.batchEquippedRequests) != 0 {
+		t.Fatalf("lite join must not query wallet appearance or vehicle resources: %+v", walletClient.batchEquippedRequests)
+	}
+	if len(profileClient.batchRequests) != 0 {
+		t.Fatalf("lite join must not call full BatchGetUsers: %+v", profileClient.batchRequests)
+	}
+	if profileClient.lastRoomBasicBatch == nil || strings.Join(int64SliceToStrings(profileClient.lastRoomBasicBatch.GetUserIds()), ",") != "101,42,102" {
+		t.Fatalf("lite join must batch only owner/viewer/mic basic users: %+v", profileClient.lastRoomBasicBatch)
+	}
+
+	var response httpkit.ResponseEnvelope
+	if err := json.NewDecoder(recorder.Body).Decode(&response); err != nil {
+		t.Fatalf("decode lite join response failed: %v", err)
+	}
+	data := response.Data.(map[string]any)
+	if _, exists := data["contribution_rank"]; exists {
+		t.Fatalf("lite join must not include contribution rank: %+v", data["contribution_rank"])
+	}
+	room := data["room"].(map[string]any)
+	if room["room_id"] != "room_lite" || room["online_count"].(float64) != 200 {
+		t.Fatalf("lite join must keep core room fields and online_count: %+v", room)
+	}
+	profiles := data["profiles"].([]any)
+	if len(profiles) != 3 {
+		t.Fatalf("lite join must include basic profiles for owner/viewer/mic only: %+v", profiles)
+	}
+	viewerProfile := map[string]any{}
+	for _, item := range profiles {
+		profile := item.(map[string]any)
+		if profile["user_id"] == "42" {
+			viewerProfile = profile
+		}
+		if profile["user_id"] == "301" {
+			t.Fatalf("lite join must not hydrate contribution-rank users: %+v", profiles)
+		}
+	}
+	if viewerProfile["username"] != "user-42" || viewerProfile["avatar"] == "" || viewerProfile["display_user_id"] == "" {
+		t.Fatalf("lite profile must carry only basic display fields: %+v", viewerProfile)
+	}
+	if _, exists := viewerProfile["avatar_frame"]; exists {
+		t.Fatalf("lite profile must not carry appearance fields: %+v", viewerProfile)
+	}
+}
+
 func TestListRoomsUsesUserRegionFromUserService(t *testing.T) {
 	profileClient := &fakeUserProfileClient{regionID: 1001}
 	regionClient := &fakeUserRegionClient{resp: &userv1.RegionResponse{Region: &userv1.Region{

services/gateway-service/internal/transport/http/roomapi/room_handler.go

@@ -37,6 +37,10 @@ const (
 	// 机器人房标记来自 room-service RoomExt；gateway 只用它决定首屏资料是否补机器人头像昵称。
 	roomExtRobotRoomKey    = "robot_room"
 	roomExtRobotUserIDsKey = "robot_user_ids"
+
+	// JoinRoom 默认保持历史完整包；lite 只保留进房首屏必要字段，把装扮/榜单等增强展示后移。
+	joinRoomResponseModeFull = "full"
+	joinRoomResponseModeLite = "lite"
 )
 
 type flexibleInt64 int64
@@ -1092,15 +1096,21 @@ func trimOptionalString(value *string) {
 // joinRoom 把进房 HTTP JSON 请求转换为 room-service JoinRoom 命令，并组装房间首屏初始化包。
 func (h *Handler) joinRoom(writer http.ResponseWriter, request *http.Request) {
 	var body struct {
-		RoomID    string `json:"room_id"`
-		CommandID string `json:"command_id"`
-		Role      string `json:"role"`
-		Password  string `json:"password"`
+		RoomID       string `json:"room_id"`
+		CommandID    string `json:"command_id"`
+		Role         string `json:"role"`
+		Password     string `json:"password"`
+		ResponseMode string `json:"response_mode"`
 	}
 
 	if !httpkit.Decode(writer, request, &body) {
 		return
 	}
+	responseMode, ok := joinRoomResponseMode(request, body.ResponseMode)
+	if !ok {
+		httpkit.WriteError(writer, request, http.StatusBadRequest, httpkit.CodeInvalidArgument, "invalid response_mode")
+		return
+	}
 	actorSnapshot, err := h.resolveRoomActorJoinSnapshot(request)
 	if err != nil {
 		httpkit.WriteRPCError(writer, request, err)
@@ -1115,16 +1125,42 @@ func (h *Handler) joinRoom(writer http.ResponseWriter, request *http.Request) {
 		ActorRegionId:       actorSnapshot.regionID,
 		ActorDisplayProfile: actorSnapshot.displayProfile,
 		// 座驾快照在进房命令提交前生成；room-service 只保存快照，不回查 wallet。
-		EntryVehicle: h.joinRoomEntryVehicleSnapshot(request),
+		EntryVehicle: h.joinRoomEntryVehicleSnapshot(request, responseMode),
+		ResponseMode: responseMode,
 	})
 	if err != nil {
 		httpkit.WriteRPCError(writer, request, err)
 		return
 	}
+	if responseMode == joinRoomResponseModeLite {
+		httpkit.WriteOK(writer, request, h.joinRoomInitialLiteData(request, body.RoomID, resp))
+		return
+	}
 	httpkit.WriteOK(writer, request, h.joinRoomInitialData(request, body.RoomID, resp))
 }
 
-func (h *Handler) joinRoomEntryVehicleSnapshot(request *http.Request) *roomv1.RoomEntryVehicleSnapshot {
+func joinRoomResponseMode(request *http.Request, bodyMode string) (string, bool) {
+	mode := strings.TrimSpace(bodyMode)
+	if mode == "" {
+		mode = strings.TrimSpace(request.URL.Query().Get("response_mode"))
+	}
+	if mode == "" {
+		return joinRoomResponseModeFull, true
+	}
+	mode = strings.ToLower(mode)
+	switch mode {
+	case joinRoomResponseModeFull, joinRoomResponseModeLite:
+		return mode, true
+	default:
+		return "", false
+	}
+}
+
+func (h *Handler) joinRoomEntryVehicleSnapshot(request *http.Request, responseMode string) *roomv1.RoomEntryVehicleSnapshot {
+	if responseMode == joinRoomResponseModeLite {
+		// lite 进房只提交 presence 必需事实；座驾属于入场展示增强，后续由资料/装扮接口补齐。
+		return nil
+	}
 	if h.walletClient == nil {
 		// 座驾只影响进房展示，不应该因为 wallet 暂不可用阻断 JoinRoom。
 		return nil
@@ -1198,6 +1234,30 @@ func (h *Handler) joinRoomInitialData(request *http.Request, requestedRoomID str
 	}
 }
 
+func (h *Handler) joinRoomInitialLiteData(request *http.Request, requestedRoomID string, resp *roomv1.JoinRoomResponse) joinRoomLiteData {
+	if resp == nil {
+		return joinRoomLiteData{}
+	}
+	viewerUserID := auth.UserIDFromContext(request.Context())
+	snapshot := resp.GetRoom()
+	roomID := snapshot.GetRoomId()
+	if roomID == "" {
+		// lite 和完整包共用同一兜底，避免异常上游只回 result 时客户端拿不到 IM/RTC 房间 ID。
+		roomID = strings.TrimSpace(requestedRoomID)
+	}
+
+	return joinRoomLiteData{
+		Result:       commandResultDataFromProto(resp.GetResult()),
+		Room:         roomInitialRoomDataFromSnapshot(snapshot, roomID),
+		Viewer:       roomViewerDataFromProto(resp.GetUser(), viewerUserID),
+		Seats:        roomSeatDataFromSnapshot(snapshot),
+		Profiles:     h.roomInitialBasicProfiles(request, snapshot, viewerUserID),
+		IM:           roomIMData{GroupID: roomIMGroupID(roomID), NeedJoinGroup: true},
+		RTC:          h.joinRoomRTCData(roomID, viewerUserID),
+		ServerTimeMS: resp.GetResult().GetServerTimeMs(),
+	}
+}
+
 func (h *Handler) joinRoomRTCData(roomID string, viewerUserID int64) roomRTCData {
 	rtc := roomRTCData{NeedToken: true}
 	token, err := h.generateTencentRTCToken(viewerUserID, roomID)
@@ -1219,6 +1279,50 @@ func (h *Handler) roomInitialProfiles(request *http.Request, snapshot *roomv1.Ro
 	return h.roomDisplayProfiles(request, userIDs)
 }
 
+func (h *Handler) roomInitialBasicProfiles(request *http.Request, snapshot *roomv1.RoomSnapshot, viewerUserID int64) []roomBasicProfileData {
+	userIDs := roomInitialBasicProfileUserIDs(snapshot, viewerUserID)
+	profileMap := h.roomBasicProfileMap(request, userIDs)
+	profiles := make([]roomBasicProfileData, 0, len(userIDs))
+	for _, userID := range userIDs {
+		if profile, ok := profileMap[userID]; ok {
+			profiles = append(profiles, profile)
+		}
+	}
+	return profiles
+}
+
+func (h *Handler) roomBasicProfileMap(request *http.Request, userIDs []int64) map[int64]roomBasicProfileData {
+	if h.userProfileClient == nil {
+		return nil
+	}
+	userIDs = uniquePositiveUserIDs(userIDs)
+	if len(userIDs) == 0 {
+		return nil
+	}
+	resp, err := h.userProfileClient.BatchGetRoomBasicUsers(request.Context(), &userv1.BatchGetRoomBasicUsersRequest{
+		Meta:    httpkit.UserMeta(request, ""),
+		UserIds: userIDs,
+	})
+	if err != nil {
+		// lite 首屏资料是展示兜底，失败不能回滚已经成功的进房 presence。
+		return nil
+	}
+	profiles := make(map[int64]roomBasicProfileData, len(resp.GetUsers()))
+	for _, userID := range userIDs {
+		user := resp.GetUsers()[userID]
+		if user == nil {
+			continue
+		}
+		profiles[userID] = roomBasicProfileData{
+			UserID:        formatOptionalUserID(user.GetUserId()),
+			Username:      strings.TrimSpace(user.GetUsername()),
+			Avatar:        strings.TrimSpace(user.GetAvatar()),
+			DisplayUserID: strings.TrimSpace(user.GetDisplayUserId()),
+		}
+	}
+	return profiles
+}
+
 // roomHeartbeat 把客户端显式心跳转换为 room-service presence refresh 命令。
 func (h *Handler) roomHeartbeat(writer http.ResponseWriter, request *http.Request) {
 	var body struct {

services/gateway-service/internal/transport/http/roomapi/room_view.go

@@ -73,6 +73,17 @@ type joinRoomData struct {
 	ServerTimeMS     int64                    `json:"server_time_ms"`
 }
 
+type joinRoomLiteData struct {
+	Result       roomCommandResultData  `json:"result"`
+	Room         roomInitialData        `json:"room"`
+	Viewer       roomViewerData         `json:"viewer"`
+	Seats        []roomSeatData         `json:"seats"`
+	Profiles     []roomBasicProfileData `json:"profiles"`
+	IM           roomIMData             `json:"im"`
+	RTC          roomRTCData            `json:"rtc"`
+	ServerTimeMS int64                  `json:"server_time_ms"`
+}
+
 type roomDetailData struct {
 	Room         roomInitialData          `json:"room"`
 	Viewer       roomViewerData           `json:"viewer"`
@@ -176,6 +187,13 @@ type roomDisplayProfileData struct {
 	Charm               int64            `json:"charm"`
 }
 
+type roomBasicProfileData struct {
+	UserID        string `json:"user_id"`
+	Username      string `json:"username"`
+	Avatar        string `json:"avatar"`
+	DisplayUserID string `json:"display_user_id"`
+}
+
 type roomGiftPanelData struct {
 	CoinBalance     int64                   `json:"coin_balance"`
 	Recipients      []roomGiftRecipientData `json:"recipients"`
@@ -797,6 +815,11 @@ func roomInitialRoomDataFromSnapshot(snapshot *roomv1.RoomSnapshot, roomID strin
 		roomShortID = ext["room_short_id"]
 	}
 	seatCount, occupiedSeatCount := roomSeatCounts(snapshot)
+	onlineCount := snapshot.GetOnlineCount()
+	if onlineCount <= 0 && len(snapshot.GetOnlineUsers()) > 0 {
+		// 老快照或非 lite 上游可能还没有 online_count 字段；此时用明细长度保持兼容。
+		onlineCount = int32(len(snapshot.GetOnlineUsers()))
+	}
 	return roomInitialData{
 		RoomID:            roomID,
 		IMGroupID:         roomIMGroupID(roomID),
@@ -811,7 +834,7 @@ func roomInitialRoomDataFromSnapshot(snapshot *roomv1.RoomSnapshot, roomID strin
 		ChatEnabled:       snapshot.GetChatEnabled(),
 		Locked:            snapshot.GetLocked(),
 		Heat:              snapshot.GetHeat(),
-		OnlineCount:       int32(len(snapshot.GetOnlineUsers())),
+		OnlineCount:       onlineCount,
 		SeatCount:         seatCount,
 		OccupiedSeatCount: occupiedSeatCount,
 		VisibleRegionID:   snapshot.GetVisibleRegionId(),
@@ -967,6 +990,25 @@ func roomInitialProfileUserIDs(snapshot *roomv1.RoomSnapshot, viewerUserID int64
 	return userIDs
 }
 
+func roomInitialBasicProfileUserIDs(snapshot *roomv1.RoomSnapshot, viewerUserID int64) []int64 {
+	seen := map[int64]bool{}
+	userIDs := make([]int64, 0, len(snapshot.GetMicSeats())+2)
+	add := func(userID int64) {
+		if userID <= 0 || seen[userID] {
+			return
+		}
+		seen[userID] = true
+		userIDs = append(userIDs, userID)
+	}
+
+	add(snapshot.GetOwnerUserId())
+	add(viewerUserID)
+	for _, seat := range snapshot.GetMicSeats() {
+		add(seat.GetUserId())
+	}
+	return userIDs
+}
+
 func roomOnlineUserDataFromProto(resp *roomv1.ListRoomOnlineUsersResponse, profiles map[int64]roomDisplayProfileData) roomOnlineUsersData {
 	if resp == nil {
 		return roomOnlineUsersData{}

services/room-service/internal/room/service/current_room.go

@@ -9,6 +9,7 @@ import (
 	"hyapp/pkg/appcode"
 	"hyapp/pkg/logx"
 	"hyapp/pkg/xerr"
+	"hyapp/services/room-service/internal/room/command"
 	"hyapp/services/room-service/internal/room/state"
 )
 
@@ -109,6 +110,49 @@ func (s *Service) projectRoomPresenceBestEffort(ctx context.Context, snapshot *r
 	}
 }
 
+// projectRoomPresenceForCommandBestEffort 按命令类型选择最小投影；Join/Leave 热路径不能再重写整房间在线集合。
+func (s *Service) projectRoomPresenceForCommandBestEffort(ctx context.Context, cmd command.Command, snapshot *roomv1.RoomSnapshot, joinedUser *roomv1.RoomUser) {
+	switch cmd.Type() {
+	case (command.JoinRoom{}).Type():
+		s.upsertJoinedRoomPresenceBestEffort(ctx, snapshot, cmd.ActorUserID(), joinedUser)
+	case (command.LeaveRoom{}).Type():
+		s.markLeftRoomPresenceBestEffort(ctx, snapshot, cmd.ActorUserID())
+	default:
+		// Kick/Close/SystemEvict/Mic 变更仍先保留全量投影，确保复杂状态收敛不因本次 Join/Leave 优化改变语义。
+		s.projectRoomPresenceBestEffort(ctx, snapshot)
+	}
+}
+
+func (s *Service) upsertJoinedRoomPresenceBestEffort(ctx context.Context, snapshot *roomv1.RoomSnapshot, userID int64, joinedUser *roomv1.RoomUser) {
+	projection := roomPresenceProjectionForUser(snapshot, userID, joinedUser, s.clock.Now().UnixMilli())
+	if projection.RoomID == "" || projection.UserID <= 0 {
+		return
+	}
+	if err := s.repository.UpsertRoomUserPresence(ctx, projection); err != nil {
+		logx.Error(ctx, "room_presence_join_project_failed", err,
+			slog.String("component", "room_presence_projector"),
+			slog.String("room_id", projection.RoomID),
+			slog.Int64("user_id", projection.UserID),
+			slog.Int64("room_version", projection.RoomVersion),
+		)
+	}
+}
+
+func (s *Service) markLeftRoomPresenceBestEffort(ctx context.Context, snapshot *roomv1.RoomSnapshot, userID int64) {
+	projection := roomPresenceLeaveProjection(snapshot, userID, s.clock.Now().UnixMilli())
+	if projection.RoomID == "" || projection.UserID <= 0 {
+		return
+	}
+	if err := s.repository.MarkRoomUserPresenceLeft(ctx, projection); err != nil {
+		logx.Error(ctx, "room_presence_leave_project_failed", err,
+			slog.String("component", "room_presence_projector"),
+			slog.String("room_id", projection.RoomID),
+			slog.Int64("user_id", projection.UserID),
+			slog.Int64("room_version", projection.RoomVersion),
+		)
+	}
+}
+
 // roomPresenceProjectionFromSnapshot 把 Room Cell 快照压缩成用户当前房间读模型。
 // 读模型只保存恢复入口需要的字段，不复制完整 RoomState，也不作为权限权威来源。
 func roomPresenceProjectionFromSnapshot(snapshot *roomv1.RoomSnapshot, updatedAtMS int64) RoomPresenceSnapshot {
@@ -161,6 +205,53 @@ func roomPresenceProjectionFromSnapshot(snapshot *roomv1.RoomSnapshot, updatedAt
 	}
 }
 
+func roomPresenceProjectionForUser(snapshot *roomv1.RoomSnapshot, userID int64, user *roomv1.RoomUser, updatedAtMS int64) RoomPresence {
+	if snapshot == nil || snapshot.GetRoomId() == "" || snapshot.GetStatus() != state.RoomStatusActive || userID <= 0 {
+		return RoomPresence{}
+	}
+	if user == nil || user.GetUserId() != userID {
+		user = findProtoUser(snapshot, userID)
+	}
+	if user == nil || user.GetUserId() <= 0 {
+		return RoomPresence{}
+	}
+	entry := RoomPresence{
+		AppCode:      snapshot.GetAppCode(),
+		UserID:       user.GetUserId(),
+		RoomID:       snapshot.GetRoomId(),
+		Role:         user.GetRole(),
+		RoomVersion:  snapshot.GetVersion(),
+		Status:       roomPresenceStatusActive,
+		JoinedAtMS:   user.GetJoinedAtMs(),
+		LastSeenAtMS: user.GetLastSeenAtMs(),
+		UpdatedAtMS:  updatedAtMS,
+	}
+	for _, seat := range snapshot.GetMicSeats() {
+		if seat.GetUserId() != user.GetUserId() {
+			continue
+		}
+		// JoinRoom 可能是重连到已在麦用户；单用户投影仍要保留麦上发流状态。
+		entry.PublishState = seat.GetPublishState()
+		entry.MicSessionID = seat.GetMicSessionId()
+		break
+	}
+	return entry
+}
+
+func roomPresenceLeaveProjection(snapshot *roomv1.RoomSnapshot, userID int64, updatedAtMS int64) RoomPresence {
+	if snapshot == nil || snapshot.GetRoomId() == "" || userID <= 0 {
+		return RoomPresence{}
+	}
+	return RoomPresence{
+		AppCode:     snapshot.GetAppCode(),
+		UserID:      userID,
+		RoomID:      snapshot.GetRoomId(),
+		RoomVersion: snapshot.GetVersion(),
+		Status:      roomPresenceStatusLeft,
+		UpdatedAtMS: updatedAtMS,
+	}
+}
+
 // containsUserID 是当前房间恢复入口的本地集合查询，独立保留便于后续替换为二分查找。
 func containsUserID(values []int64, target int64) bool {
 	return slices.Contains(values, target)

services/room-service/internal/room/service/online_users_test.go

@@ -94,6 +94,95 @@ func TestListRoomOnlineUsersReturnsOwnerAdminRoleAndGiftValue(t *testing.T) {
 	t.Logf("online users response items: %s", payload)
 }
 
+func TestJoinLeaveRoomUpdatesPresenceIncrementally(t *testing.T) {
+	ctx := context.Background()
+	repository := mysqltest.NewRepository(t)
+	now := &fixedRoomRocketClock{now: time.Date(2026, 5, 27, 13, 0, 0, 0, time.UTC)}
+	svc := newRocketTestService(t, repository, &rocketTestWallet{}, now)
+
+	roomID := "room-presence-incremental"
+	ownerID := int64(1101)
+	viewerID := int64(1102)
+	createRocketRoom(t, ctx, svc, roomID, ownerID, 9001)
+	joinRocketRoom(t, ctx, svc, roomID, viewerID)
+
+	onlineResp, err := svc.ListRoomOnlineUsers(ctx, &roomv1.ListRoomOnlineUsersRequest{
+		Meta:         &roomv1.RequestMeta{AppCode: appcode.Default, RoomId: roomID},
+		RoomId:       roomID,
+		ViewerUserId: ownerID,
+		Page:         1,
+		PageSize:     10,
+	})
+	if err != nil {
+		t.Fatalf("list online users after join failed: %v", err)
+	}
+	if item := onlineUserItemByID(onlineResp.GetItems(), viewerID); item == nil || item.GetRole() != "audience" {
+		t.Fatalf("join must upsert viewer active presence: %+v", onlineResp.GetItems())
+	}
+
+	if _, err := svc.LeaveRoom(ctx, &roomv1.LeaveRoomRequest{Meta: rocketMeta(roomID, viewerID, "presence-incremental-leave")}); err != nil {
+		t.Fatalf("leave room failed: %v", err)
+	}
+	onlineResp, err = svc.ListRoomOnlineUsers(ctx, &roomv1.ListRoomOnlineUsersRequest{
+		Meta:         &roomv1.RequestMeta{AppCode: appcode.Default, RoomId: roomID},
+		RoomId:       roomID,
+		ViewerUserId: ownerID,
+		Page:         1,
+		PageSize:     10,
+	})
+	if err != nil {
+		t.Fatalf("list online users after leave failed: %v", err)
+	}
+	if item := onlineUserItemByID(onlineResp.GetItems(), viewerID); item != nil {
+		t.Fatalf("leave must mark only viewer presence left: %+v", onlineResp.GetItems())
+	}
+}
+
+func TestMarkRoomUserPresenceLeftDoesNotClearAnotherRoom(t *testing.T) {
+	ctx := appcode.WithContext(context.Background(), appcode.Default)
+	repository := mysqltest.NewRepository(t)
+	userID := int64(1201)
+
+	if err := repository.UpsertRoomUserPresence(ctx, roomservice.RoomPresence{
+		AppCode:      appcode.Default,
+		UserID:       userID,
+		RoomID:       "room-current-active",
+		Role:         "audience",
+		RoomVersion:  2,
+		JoinedAtMS:   1000,
+		LastSeenAtMS: 1000,
+		UpdatedAtMS:  1000,
+	}); err != nil {
+		t.Fatalf("upsert current room presence failed: %v", err)
+	}
+	if err := repository.MarkRoomUserPresenceLeft(ctx, roomservice.RoomPresence{
+		AppCode:     appcode.Default,
+		UserID:      userID,
+		RoomID:      "room-old-left",
+		RoomVersion: 3,
+		UpdatedAtMS: 2000,
+	}); err != nil {
+		t.Fatalf("mark old room presence left failed: %v", err)
+	}
+
+	presence, exists, err := repository.GetCurrentRoomPresence(ctx, userID)
+	if err != nil {
+		t.Fatalf("get current room presence failed: %v", err)
+	}
+	if !exists || presence.RoomID != "room-current-active" || presence.Status != "active" {
+		t.Fatalf("old room leave projection must not clear newer room presence: exists=%v presence=%+v", exists, presence)
+	}
+}
+
+func onlineUserItemByID(items []*roomv1.RoomOnlineUser, userID int64) *roomv1.RoomOnlineUser {
+	for _, item := range items {
+		if item.GetUserId() == userID {
+			return item
+		}
+	}
+	return nil
+}
+
 func TestSendGiftPassesHostPeriodScopeToWallet(t *testing.T) {
 	ctx := context.Background()
 	repository := mysqltest.NewRepository(t)

services/room-service/internal/room/service/pipeline.go

@@ -178,7 +178,7 @@ func (s *Service) mutateRoom(ctx context.Context, cmd command.Command, replayabl
 		// 列表读模型最终一致，失败只记录日志，不回滚已经提交的 Room Cell 命令。
 		s.projectRoomListBestEffort(ctx, result.snapshot)
 		// 当前房间恢复读模型同样最终一致；权威校验仍以 Room Cell 快照为准。
-		s.projectRoomPresenceBestEffort(ctx, result.snapshot)
+		s.projectRoomPresenceForCommandBestEffort(ctx, cmd, result.snapshot, result.user)
 		// 跨房间贡献榜是 Redis 轻量读模型，不能影响已提交的房间状态和账务事实。
 		s.recordRoomGiftLeaderboardBestEffort(ctx, result.roomGiftLeaderboard)
 		projectionMS = elapsedMS(projectionStartedAt)

services/room-service/internal/room/service/presence.go

@@ -19,6 +19,8 @@ import (
 	"hyapp/services/room-service/internal/room/state"
 )
 
+const joinRoomResponseModeLite = "lite"
+
 // JoinRoom 把用户业务态接入房间。
 func (s *Service) JoinRoom(ctx context.Context, req *roomv1.JoinRoomRequest) (*roomv1.JoinRoomResponse, error) {
 	ctx = contextFromMeta(ctx, req.GetMeta())
@@ -133,10 +135,38 @@ func (s *Service) JoinRoom(ctx context.Context, req *roomv1.JoinRoomRequest) (*r
 	return &roomv1.JoinRoomResponse{
 		Result: commandResult(result.applied, result.snapshot.GetVersion(), s.clock.Now()),
 		User:   result.user,
-		Room:   result.snapshot,
+		Room:   joinRoomResponseSnapshot(result.snapshot, req.GetResponseMode()),
 	}, nil
 }
 
+func joinRoomResponseSnapshot(snapshot *roomv1.RoomSnapshot, responseMode string) *roomv1.RoomSnapshot {
+	if strings.ToLower(strings.TrimSpace(responseMode)) != joinRoomResponseModeLite || snapshot == nil {
+		return snapshot
+	}
+	onlineCount := snapshot.GetOnlineCount()
+	if onlineCount <= 0 && len(snapshot.GetOnlineUsers()) > 0 {
+		onlineCount = int32(len(snapshot.GetOnlineUsers()))
+	}
+	// lite 只裁剪返回给 gateway 的快照；Room Cell 提交、持久化、projection、outbox 都已经使用完整 snapshot。
+	return &roomv1.RoomSnapshot{
+		RoomId:          snapshot.GetRoomId(),
+		OwnerUserId:     snapshot.GetOwnerUserId(),
+		Mode:            snapshot.GetMode(),
+		Status:          snapshot.GetStatus(),
+		ChatEnabled:     snapshot.GetChatEnabled(),
+		MicSeats:        snapshot.GetMicSeats(),
+		RoomExt:         snapshot.GetRoomExt(),
+		Heat:            snapshot.GetHeat(),
+		Version:         snapshot.GetVersion(),
+		AppCode:         snapshot.GetAppCode(),
+		RoomShortId:     snapshot.GetRoomShortId(),
+		VisibleRegionId: snapshot.GetVisibleRegionId(),
+		Locked:          snapshot.GetLocked(),
+		Rocket:          snapshot.GetRocket(),
+		OnlineCount:     onlineCount,
+	}
+}
+
 func userDisplayProfileFromProto(item *roomv1.RoomUserDisplayProfile) command.UserDisplayProfile {
 	if item == nil || item.GetUserId() <= 0 {
 		return command.UserDisplayProfile{}

services/room-service/internal/room/service/repository.go

@@ -784,6 +784,10 @@ type RoomListStore interface {
 type PresenceStore interface {
 	// ProjectRoomPresence 用最新快照刷新用户当前房间读模型；失败不应破坏 Room Cell 已提交状态。
 	ProjectRoomPresence(ctx context.Context, snapshot RoomPresenceSnapshot) error
+	// UpsertRoomUserPresence 只刷新单个用户 active presence，服务 JoinRoom/Heartbeat 等单用户热路径。
+	UpsertRoomUserPresence(ctx context.Context, presence RoomPresence) error
+	// MarkRoomUserPresenceLeft 只把指定用户在指定房间标记为 left，避免 LeaveRoom 重新写整房间在线用户。
+	MarkRoomUserPresenceLeft(ctx context.Context, presence RoomPresence) error
 	// GetCurrentRoomPresence 查询用户当前 active 房间 presence，不扫描房间列表或快照。
 	GetCurrentRoomPresence(ctx context.Context, userID int64) (RoomPresence, bool, error)
 	// ListRoomOnlineUsers 查询房间 active 在线用户分页，不读取完整 RoomSnapshot。

services/room-service/internal/room/service/room_rocket_test.go

@@ -151,6 +151,42 @@ func TestRepeatJoinRoomPublishesEntryBroadcastDirectIMOnly(t *testing.T) {
 	}
 }
 
+func TestJoinRoomLiteTrimsResponseSnapshotOnly(t *testing.T) {
+	ctx := context.Background()
+	repository := mysqltest.NewRepository(t)
+	now := &fixedRoomRocketClock{now: time.Date(2026, 6, 27, 12, 0, 0, 0, time.UTC)}
+	svc := newRocketTestServiceWithDirectIM(t, repository, &rocketTestWallet{}, now, nil, newRecordingRoomDirectIMPublisher())
+
+	roomID := "room-lite-response-snapshot"
+	createRocketRoom(t, ctx, svc, roomID, 1001, 9001)
+	joinRocketRoom(t, ctx, svc, roomID, 1002)
+	joinRocketRoom(t, ctx, svc, roomID, 1003)
+
+	resp, err := svc.JoinRoom(ctx, &roomv1.JoinRoomRequest{
+		Meta:         roomservice.NewRequestMeta(roomID, 1004),
+		Role:         "audience",
+		ResponseMode: "lite",
+	})
+	if err != nil {
+		t.Fatalf("lite join room failed: %v", err)
+	}
+	if len(resp.GetRoom().GetOnlineUsers()) != 0 || len(resp.GetRoom().GetGiftRank()) != 0 || len(resp.GetRoom().GetAdminUserIds()) != 0 {
+		t.Fatalf("lite response must trim heavy room arrays: %+v", resp.GetRoom())
+	}
+
+	snapshot, err := svc.GetRoomSnapshot(ctx, &roomv1.GetRoomSnapshotRequest{
+		Meta:         &roomv1.RequestMeta{AppCode: appcode.Default, RoomId: roomID},
+		RoomId:       roomID,
+		ViewerUserId: 1004,
+	})
+	if err != nil {
+		t.Fatalf("snapshot after lite join failed: %v", err)
+	}
+	if got, want := resp.GetRoom().GetOnlineCount(), int32(len(snapshot.GetRoom().GetOnlineUsers())); got != want || want == 0 {
+		t.Fatalf("lite response must keep accurate online_count without mutating stored snapshot: got=%d want=%d snapshot=%+v", got, want, snapshot.GetRoom())
+	}
+}
+
 func (w *rocketTestWallet) DebitGift(_ context.Context, req *walletv1.DebitGiftRequest) (*walletv1.DebitGiftResponse, error) {
 	w.lastDebit = req
 	w.debitRequests = append(w.debitRequests, req)

services/room-service/internal/room/state/state.go

@@ -465,6 +465,7 @@ func (s *RoomState) ToProto() *roomv1.RoomSnapshot {
 		Locked:          s.RoomPasswordHash != "",
 		Rocket:          rocketStateToProto(s.Rocket),
 		BanStates:       sortedModerationStates(s.BanUsers),
+		OnlineCount:     int32(len(users)),
 	}
 }
 

services/room-service/internal/storage/mysql/presence.go

@@ -77,6 +77,62 @@ func (r *Repository) ProjectRoomPresence(ctx context.Context, snapshot roomservi
 	return tx.Commit()
 }
 
+// UpsertRoomUserPresence 只写入单个 active 用户，避免 JoinRoom 为整房间在线用户产生 O(N) 写放大。
+func (r *Repository) UpsertRoomUserPresence(ctx context.Context, presence roomservice.RoomPresence) error {
+	appCode := normalizedRecordAppCode(ctx, presence.AppCode)
+	if presence.UserID <= 0 || strings.TrimSpace(presence.RoomID) == "" {
+		return nil
+	}
+	_, err := r.db.ExecContext(ctx,
+		`INSERT INTO room_user_presence (
+		   app_code, user_id, room_id, role, publish_state, mic_session_id, room_version, status, joined_at_ms, last_seen_at_ms, updated_at_ms
+		 ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+		 ON DUPLICATE KEY UPDATE
+		   room_id = VALUES(room_id),
+		   role = VALUES(role),
+		   publish_state = VALUES(publish_state),
+		   mic_session_id = VALUES(mic_session_id),
+		   room_version = VALUES(room_version),
+		   status = VALUES(status),
+		   joined_at_ms = VALUES(joined_at_ms),
+		   last_seen_at_ms = VALUES(last_seen_at_ms),
+		   updated_at_ms = VALUES(updated_at_ms)`,
+		appCode,
+		presence.UserID,
+		presence.RoomID,
+		presence.Role,
+		presence.PublishState,
+		presence.MicSessionID,
+		presence.RoomVersion,
+		roomPresenceStatusActiveSQL,
+		presence.JoinedAtMS,
+		presence.LastSeenAtMS,
+		presence.UpdatedAtMS,
+	)
+	return err
+}
+
+// MarkRoomUserPresenceLeft 只关闭指定用户在指定房间的 active presence，避免旧离房投影误伤新房间。
+func (r *Repository) MarkRoomUserPresenceLeft(ctx context.Context, presence roomservice.RoomPresence) error {
+	appCode := normalizedRecordAppCode(ctx, presence.AppCode)
+	if presence.UserID <= 0 || strings.TrimSpace(presence.RoomID) == "" {
+		return nil
+	}
+	_, err := r.db.ExecContext(ctx,
+		`UPDATE room_user_presence
+		 SET status = ?, publish_state = '', mic_session_id = '', room_version = ?, updated_at_ms = ?
+		 WHERE app_code = ? AND user_id = ? AND room_id = ? AND status = ?`,
+		roomPresenceStatusLeftSQL,
+		presence.RoomVersion,
+		presence.UpdatedAtMS,
+		appCode,
+		presence.UserID,
+		presence.RoomID,
+		roomPresenceStatusActiveSQL,
+	)
+	return err
+}
+
 // GetCurrentRoomPresence 查询用户当前 active 房间，不扫描发现页列表。
 func (r *Repository) GetCurrentRoomPresence(ctx context.Context, userID int64) (roomservice.RoomPresence, bool, error) {
 	row := r.db.QueryRowContext(ctx,

services/user-service/internal/domain/user/user.go

@@ -294,6 +294,18 @@ type User struct {
 	UpdatedAtMs int64
 }
 
+// RoomBasicUser 是房间首屏热路径使用的最小用户展示资料，不能混入国家、靓号详情或装扮字段。
+type RoomBasicUser struct {
+	// UserID 是系统内部不可变用户 ID，调用方用它和麦位/房主/当前用户状态关联。
+	UserID int64
+	// Username 是用户当前基础昵称；为空时客户端按 display_user_id 或 user_id 兜底。
+	Username string
+	// Avatar 是用户当前基础头像 URL；装扮头像框不属于这个结构。
+	Avatar string
+	// DisplayUserID 是房间首屏展示短号；过期靓号在 SQL 内兜底为默认短号。
+	DisplayUserID string
+}
+
 // ProfileStats 是我的页顶部统计 read model，只保存预聚合计数。
 type ProfileStats struct {
 	// AppCode 是统计所属 App，关系链和礼物统计都必须在 App 内隔离。

services/user-service/internal/service/user/moderation_test.go

@@ -216,6 +216,10 @@ func (r *fakeModerationRepository) BatchGetUsers(context.Context, []int64) (map[
 	return nil, nil
 }
 
+func (r *fakeModerationRepository) BatchGetRoomBasicUsers(context.Context, []int64) (map[int64]userdomain.RoomBasicUser, error) {
+	return nil, nil
+}
+
 func (r *fakeModerationRepository) FindInviteReferrerByCode(_ context.Context, appCode string, inviteCode string) (userdomain.User, error) {
 	r.lastFindAppCode = appCode
 	r.lastFindInviteCode = inviteCode

services/user-service/internal/service/user/service.go

@@ -45,6 +45,8 @@ type UserRepository interface {
 	BusinessUserLookup(ctx context.Context, keyword string, numericKeyword bool, pageSize int32) ([]userdomain.BusinessUserLookupItem, error)
 	// BatchGetUsers 批量查询用户主状态，缺失用户不应返回占位对象。
 	BatchGetUsers(ctx context.Context, userIDs []int64) (map[int64]userdomain.User, error)
+	// BatchGetRoomBasicUsers 批量查询房间首屏最小用户资料，不触发完整用户主状态投影。
+	BatchGetRoomBasicUsers(ctx context.Context, userIDs []int64) (map[int64]userdomain.RoomBasicUser, error)
 	// GetInviteAttribution 按被邀请用户读取邀请归因快照；无关系时返回 Found=false。
 	GetInviteAttribution(ctx context.Context, invitedUserID int64) (invitedomain.Attribution, error)
 	// FindInviteReferrerByCode 按 active 邀请码读取归属用户，供 H5 绑定页搜索同区域邀请人。

services/user-service/internal/service/user/user.go

@@ -94,6 +94,25 @@ func (s *Service) BatchGetUsers(ctx context.Context, userIDs []int64) (map[int64
 	return users, nil
 }
 
+// BatchGetRoomBasicUsers 批量查询房间首屏最小用户资料。
+func (s *Service) BatchGetRoomBasicUsers(ctx context.Context, userIDs []int64) (map[int64]userdomain.RoomBasicUser, error) {
+	if len(userIDs) == 0 {
+		// 空批量请求返回空 map，gateway 可以直接输出空 profiles。
+		return map[int64]userdomain.RoomBasicUser{}, nil
+	}
+	for _, userID := range userIDs {
+		if userID <= 0 {
+			// room-service 只接受正 user_id；这里继续对调用方输入做边界收敛。
+			return nil, xerr.New(xerr.InvalidArgument, "user_ids contains invalid value")
+		}
+	}
+	if s.userRepository == nil {
+		// 房间热路径也不能绕过 owner repository；无存储时明确返回不可用。
+		return nil, xerr.New(xerr.Unavailable, "user repository is not configured")
+	}
+	return s.userRepository.BatchGetRoomBasicUsers(ctx, userIDs)
+}
+
 // ListUserIDs returns active user IDs for low-frequency backend fanout tasks.
 func (s *Service) ListUserIDs(ctx context.Context, filter userdomain.UserIDPageFilter) ([]int64, int64, bool, error) {
 	if s.userRepository == nil {

services/user-service/internal/storage/mysql/user/repository.go

@@ -92,6 +92,49 @@ func (r *Repository) BatchGetUsers(ctx context.Context, userIDs []int64) (map[in
 	return result, rows.Err()
 }
 
+// BatchGetRoomBasicUsers 只读取房间首屏需要的基础展示字段，避免 JoinRoom lite 触发完整用户投影。
+func (r *Repository) BatchGetRoomBasicUsers(ctx context.Context, userIDs []int64) (map[int64]userdomain.RoomBasicUser, error) {
+	placeholders := make([]string, 0, len(userIDs))
+	args := make([]any, 0, len(userIDs)+2)
+	nowMS := time.Now().UTC().UnixMilli()
+	args = append(args, nowMS)
+	for _, userID := range userIDs {
+		placeholders = append(placeholders, "?")
+		args = append(args, userID)
+	}
+	args = append(args, appcode.FromContext(ctx))
+
+	rows, err := r.db.QueryContext(ctx, fmt.Sprintf(`
+		SELECT user_id,
+		       COALESCE(username, ''),
+		       COALESCE(avatar, ''),
+		       CASE
+		         WHEN current_display_user_id_kind <> 'default'
+		          AND COALESCE(current_display_user_id_expires_at_ms, 0) > 0
+		          AND current_display_user_id_expires_at_ms <= ?
+		         THEN default_display_user_id
+		         ELSE current_display_user_id
+		       END
+		FROM users FORCE INDEX (PRIMARY)
+		WHERE user_id IN (%s)
+		  AND app_code = ?
+	`, strings.Join(placeholders, ",")), args...)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	result := make(map[int64]userdomain.RoomBasicUser, len(userIDs))
+	for rows.Next() {
+		var user userdomain.RoomBasicUser
+		if err := rows.Scan(&user.UserID, &user.Username, &user.Avatar, &user.DisplayUserID); err != nil {
+			return nil, err
+		}
+		result[user.UserID] = user
+	}
+	return result, rows.Err()
+}
+
 // ListUserIDs returns active user IDs in ascending order for cursor-based backend fanout.
 func (r *Repository) ListUserIDs(ctx context.Context, filter userdomain.UserIDPageFilter) ([]int64, error) {
 	conditions := []string{"app_code = ?", "status = ?", "user_id > ?"}

services/user-service/internal/testutil/mysqltest/mysqltest.go

@@ -129,6 +129,11 @@ func (r *Repository) BatchGetUsers(ctx context.Context, userIDs []int64) (map[in
 	return r.Repository.UserRepository().BatchGetUsers(ctx, userIDs)
 }
 
+// BatchGetRoomBasicUsers 让测试 wrapper 继续满足房间首屏基础资料查询接口。
+func (r *Repository) BatchGetRoomBasicUsers(ctx context.Context, userIDs []int64) (map[int64]userdomain.RoomBasicUser, error) {
+	return r.Repository.UserRepository().BatchGetRoomBasicUsers(ctx, userIDs)
+}
+
 // ListUserIDs 让测试 wrapper 继续满足后台 fanout 目标用户查询接口。
 func (r *Repository) ListUserIDs(ctx context.Context, filter userdomain.UserIDPageFilter) ([]int64, error) {
 	return r.Repository.UserRepository().ListUserIDs(ctx, filter)

services/user-service/internal/transport/grpc/server.go

@@ -660,6 +660,26 @@ func (s *Server) BatchGetUsers(ctx context.Context, req *userv1.BatchGetUsersReq
 	return &userv1.BatchGetUsersResponse{Users: result}, nil
 }
 
+// BatchGetRoomBasicUsers 批量返回房间首屏最小用户展示资料。
+func (s *Server) BatchGetRoomBasicUsers(ctx context.Context, req *userv1.BatchGetRoomBasicUsersRequest) (*userv1.BatchGetRoomBasicUsersResponse, error) {
+	ctx = contextWithApp(ctx, req.GetMeta())
+	users, err := s.userSvc.BatchGetRoomBasicUsers(ctx, req.GetUserIds())
+	if err != nil {
+		return nil, xerr.ToGRPCError(err)
+	}
+	result := make(map[int64]*userv1.RoomBasicUser, len(users))
+	for userID, user := range users {
+		// 只透出首屏绘制必需字段，避免 gateway lite 路径拿到完整用户主状态。
+		result[userID] = &userv1.RoomBasicUser{
+			UserId:        user.UserID,
+			Username:      user.Username,
+			Avatar:        user.Avatar,
+			DisplayUserId: user.DisplayUserID,
+		}
+	}
+	return &userv1.BatchGetRoomBasicUsersResponse{Users: result}, nil
+}
+
 // ListUserIDs 为后台 fanout 任务返回稳定递增的用户 ID 游标页。
 func (s *Server) ListUserIDs(ctx context.Context, req *userv1.ListUserIDsRequest) (*userv1.ListUserIDsResponse, error) {
 	ctx = contextWithApp(ctx, req.GetMeta())