diff --git a/.cursor/skills/spark-im-v3/SKILL.md b/.cursor/skills/spark-im-v3/SKILL.md
index 30fb772..193c051 100644
--- a/.cursor/skills/spark-im-v3/SKILL.md
+++ b/.cursor/skills/spark-im-v3/SKILL.md
@@ -95,7 +95,7 @@ Media: HTTP upload credential, message content is object key only. Frame max 64K
 Message types: text / image / voice / video / emoji / gif / file / location / system (`message/entity.Type` 1–9). `messages.content` stores serialized JSON bytes (BLOB), never a raw string. Closed type/status values: [enums.md](enums.md).
 
 TCP body is JSON envelope `{code,msg,request_id,data}`. AUTH request is `{"token","device_id","app_version","language"}` (not protobuf).
-Public TLS is Nginx `:443` SNI: HTTP cert on loopback `:8443`, IM cert on loopback `:19001` then PROXY to gnet `:9090` (host `:9000` is rustfs). See `deploy/nginx/`.
+Public TLS is Nginx `:443` SNI: HTTP cert on loopback `:8443` (`sparkapi` + `sparkr`/RustFS), IM cert on loopback `:19001` then PROXY to gnet `:9090` (host `:9000` is rustfs). See `deploy/nginx/`.
 AUTH/login rate-limit uses `reqctx.RealIP`. TaskPool workers recover panics. Deliver workers start with `RequeueStale` + `SETNX deliver:done:{msgId}`.
 
 ## When adding a feature
diff --git a/README.md b/README.md
index 409ee41..b4712b1 100644
--- a/README.md
+++ b/README.md
@@ -1,21 +1,322 @@
 # spark-server
 
-Spark IM modular monolith. Architecture: [docs/architecture-v3.md](docs/architecture-v3.md).
+Spark IM 服务端。Go 1.26 **模块化单体**（一台机器、一个进程）。公网只开 **443**，HTTP / IM / 对象存储用三个域名、Nginx SNI 分流。
 
-- Go 1.26
-- Gin HTTP on `127.0.0.1:8080`. JSON envelope `{"code","msg","request_id","data"}`. Docs: `GET /docs` (API), `/docs/enums`, `/docs/errors`. Spec: `GET /openapi.yaml`.
-- Probes: `GET /healthz` liveness; `GET /readyz` readiness (HTTP 503 when MySQL/Redis/task pool/accepting are not ready). `env: prod` (or `SPARK_ENV=prod`) rejects empty MySQL DSN, empty Redis, and the default JWT secret.
-- Logs: zap to console and/or rotating file (`log.console` / `log.file`). GORM SQL goes through the same zap. `request_id` is server-generated and returned in the response body (also as `X-Request-ID`).
-- gnet TCP on loopback (local `127.0.0.1:8090`; ECS Docker `127.0.0.1:9090` because host `:9000` is rustfs). gnet v2.10 has no built-in TLS; Nginx terminates IM TLS and forwards PROXY+plaintext. Sample: `deploy/nginx/`. `make deploy` writes image/config/logs under `/data/spark-server/`.
-- TCP Frame body is JSON `{code,msg,request_id,data}`. AUTH body: `{"token","device_id","app_version","language"}`.
-- Public entry is Nginx `:443` only (SNI split)
+仓库：<https://gitea.wyrs365.com/Spark/spark-server.git>  
+完整设计：[docs/architecture-v3.md](docs/architecture-v3.md)  
+在线协议：`GET /docs`（Swagger）、`/docs/enums`、`/docs/errors`，规范 `GET /openapi.yaml`。
 
-```bash
-make start
-make migrate
-make lint
+不上 Kafka、K8s、微服务。不要给 gnet 绑公网端口，不要在 EventLoop 里打 MySQL。
+
+---
+
+## 它做什么
+
+即时通讯：登录、好友、群、发消息、增量同步、撤回删除、媒体直传。
+
+| 层 | 职责 |
+| --- | --- |
+| 实时 | TCP 长连接（gnet）。在线推送 `MESSAGE`，心跳 30s，空闲 120s 断开 |
+| 正文 | MySQL。Snowflake `MsgId` 是主键、排序、同步游标。没有 `ConversationSeq` |
+| 会话列表 / 未读 | Redis ZSET。群热路径不写 MySQL inbox 行 |
+| 扇出 | Redis `deliver:queue` + worker。`SEND_ACK` = MySQL COMMIT **且** 入队成功 |
+| 媒体 | 客户端拿 Presigned URL 直传 RustFS。消息里只存 `object_key` |
+
+HTTP 和 TCP 调同一套 `internal/module/*/logic`。Gin handler 只做绑定和写信封。
+
+---
+
+## 生产入口
+
+| 用途 | 域名 | 说明 |
+| --- | --- | --- |
+| HTTP API | `https://sparkapi.wyrs365.com` | REST `/v1/...`，文档 `/docs` |
+| IM 长连接 | `sparkim.wyrs365.com:443` | TLS + 自定义 Frame，不是 WebSocket |
+| 对象存储 | `https://sparkr.wyrs365.com` | RustFS S3 path-style，Presigned PUT/GET |
+
+本机开发：HTTP `http://127.0.0.1:8080`，TCP 明文 `127.0.0.1:8090`。
+
+ECS 上进程只绑回环，由 Nginx 终结 TLS：
+
+```text
+客户端 :443  (ssl_preread)
+  ├─ sparkapi.wyrs365.com  → 127.0.0.1:8443 → Gin 127.0.0.1:18080
+  ├─ sparkr.wyrs365.com    → 127.0.0.1:8443 → RustFS 127.0.0.1:9000
+  └─ sparkim.wyrs365.com   → 127.0.0.1:19001 (IM TLS)
+                            → PROXY → gnet 127.0.0.1:9090
 ```
 
-`make start` runs `cmd/server` against `configs/config.yaml` (override with `make start CONFIG=path/to.yaml`). `make run` builds `bin/spark-server` first, then starts that binary.
+主机 `:9000` 是 RustFS S3，所以 IM gnet 用 **9090**。安全组只放行 443。
 
-Agent conventions live in `.cursor/rules` and `.cursor/skills/spark-im-v3`. Lint conventions live in `.golangci.yaml`.
+---
+
+## 硬约束（不要改）
+
+| ID | 规则 |
+| --- | --- |
+| C1 | 消息正文在 MySQL。Snowflake `MsgId` 是 PK / 排序 / 同步游标。没有 ConversationSeq |
+| C2 | gnet EventLoop 不调 MySQL / Redis / 对象存储 / 扇出。入站进 TaskPool；扇出走 `deliver:queue` |
+| C3 | 保密靠 TLS。Frame 只有薄头 + 可选 gzip。没有应用层 ECDH/AES |
+| C4 | 公网只有 443。gnet / Gin 绑回环 |
+| C5 | `SEND_ACK` 必须在 COMMIT **且** deliver `Push` 成功之后。入队失败不 ACK |
+| C6 | 限流 / 审计用 PROXY / `X-Real-IP` 的 `RealIP`，不用 gnet `RemoteAddr`（那是 127.0.0.1） |
+| C7 | 会话列表 / 未读 / 预览在 Redis ZSET。群热路径不 upsert MySQL inbox |
+
+热路径禁止 `context.TODO()`。推送超时不踢连接。不要把媒体字节写进 `messages.content`。
+
+---
+
+## 统一响应
+
+HTTP 与 TCP **应答 Body** 同一套信封。业务成败只看 `code` 字符串，不要用数字 `0` 比较。除 `/readyz` 未就绪是 HTTP 503 外，业务失败也是 HTTP 200。
+
+```json
+{"code":"0","msg":"ok","request_id":"3H8kPq2mN1R","data":{}}
+```
+
+| 字段 | 规则 |
+| --- | --- |
+| `code` | `"0"` 成功；其它失败。全表见 [/docs/errors](https://sparkapi.wyrs365.com/docs/errors) |
+| `msg` | 展示文案，随语言变。成功一般为 `ok` |
+| `request_id` | 服务端生成，**11 位 base62**（`0-9A-Za-z`）。客户端不用传。HTTP 同时写 Header `X-Request-ID` |
+| `data` | 成功为业务对象；失败固定 `{}`。缺字段当空对象，不要当 `null` |
+
+`request_id` 和 TCP Frame 头里的 `RequestID`（uint64）不是一回事：后者是客户端填的配对号，服务端原样带回。
+
+### HTTP 请求放哪
+
+| 位置 | 内容 |
+| --- | --- |
+| Header | `Authorization: Bearer …`、`X-Device-ID`、`X-Language` 或 `Accept-Language`、`X-App-Version`、`Content-Type` |
+| Body | POST/PATCH 业务字段。不要把 token / 语言 / device_id 塞进业务 JSON（登录 Body 带 `device_id`，刷新 Body 带 `refresh_token`） |
+| Path | 资源 id：好友 uid、群号、MsgId |
+| Query | GET 筛选 / 分页 |
+
+语言：`zh-CN`（缺省）/ `en` / `zh-TW`。网关写 `X-Real-IP`，客户端不要发。
+
+---
+
+## 登录
+
+1. （可选）`POST /v1/auth/email-codes` Body `{"email"}`。
+2. `POST /v1/auth/login` 拿 `access_token` / `refresh_token`。`device_id` 由**客户端生成并持久化**，服务端不分配；写入 JWT `did`。
+3. 其它 HTTP：`Authorization: Bearer …`，可选 `X-Device-ID`（须等于登录时的 device_id）。
+4. 续期：`POST /v1/auth/token/refresh`，Body `{"refresh_token"}`，不要带 Bearer。
+5. 在线发消息、收推送、增量同步走 **TCP**。`POST /v1/messages` 只是 HTTP 调试通道，不要当 App 主路径。
+
+测试号 `test01@spark.com`～`test10@spark.com` 可跳过发码，登录任意 `verify_code`。
+
+`uid` 就是 Snowflake `users.id`。对外展示用可变的 `spark_id`，不要把 uid 写进对象存储路径。
+
+---
+
+## HTTP 资源
+
+前缀 `/v1/{resource}`。
+
+| 组 | 路径 | 说明 |
+| --- | --- | --- |
+| 探活 | `/healthz` `/readyz` | 存活；未就绪 HTTP 503 |
+| 文档 | `/docs` `/docs/enums` `/docs/errors` `/openapi.yaml` | 无需登录 |
+| 枚举 | `GET /v1/meta/enums` | 无需登录 |
+| 认证 | `/v1/auth` | 发码、登录、刷新、登出 |
+| 用户 | `/v1/users/me` | 资料 |
+| 好友 | `/v1/friends` | 申请、同意、备注、置顶、拉黑、举报 |
+| 群 | `/v1/groups` | 创建、资料、成员、邀请、踢人、转让、解散 |
+| 文件 | `/v1/files` | 上传/下载凭证、批量、图片派生 |
+| 收藏 | `/v1/favorites` | 收藏；媒体会 Copy 到 `perm/fav/` |
+| 会话 | `/v1/conversations` | 列表、免打扰 |
+| 消息 | `/v1/messages` | 历史 / 撤回 / 删除（主路径仍是 TCP） |
+
+---
+
+## TCP 协议
+
+不是 WebSocket、不是 HTTP、不是 Protobuf。对 `sparkim.wyrs365.com:443` 做 TLS（SNI 必须是该域名），之后写二进制 Frame。
+
+### Frame（大端，固定 23 字节头）
+
+```text
+offset 0   Magic      uint16  0x5350（ASCII "SP"）
+offset 2   Version    uint8   1
+offset 3   Command    uint16
+offset 5   Flags      uint16  bit0=1 表示 Body 是 gzip
+offset 7   RequestID  uint64  客户端配对，可 0；响应原样带回
+offset 15  SequenceID uint32  请求/响应配对；PUSH_ACK 必须带回推送帧的 SequenceID
+offset 19  BodyLength uint32  Body 字节数（压缩后）
+offset 23  Body       bytes   UTF-8 JSON
+```
+
+先读 23 字节，再按 `BodyLength` 读 Body。Magic 不对或总长超过 64KB 应断开。Body ≥ 512B 且 gzip 更小时可压缩。
+
+**请求 Body 是业务 JSON，不要包信封。** 应答和 `MESSAGE` 推送才是 `{code,msg,request_id,data}`。失败时 Command 仍为请求 Command（发送失败不是 `SEND_ACK`）。
+
+| 值 | 名 | 方向 |
+| --- | --- | --- |
+| 1 | AUTH | → 请求 `{"token","device_id","app_version","language"}` |
+| 2 | HEARTBEAT | → 空 Body |
+| 3 | GENERATE_MSG_ID | → 空；应答 `data.msg_id` |
+| 4 | SEND_MESSAGE | → 与 HTTP 发消息同一 JSON |
+| 5 | SEND_ACK | ← 仅 4 的成功应答 |
+| 6 | MESSAGE | ← 推送 |
+| 7 | PUSH_ACK | → 空；`SequenceID` = 推送帧的 SequenceID |
+| 8 | READ_MESSAGE | → |
+| 9 | RECALL_MESSAGE | → `{"msg_id"}` |
+| 10 | SYNC_INBOX | → 会话列表增量 |
+| 12 | SYNC_MESSAGES | → 某会话消息增量 |
+| 14 | KICK | ← 同设备顶号 |
+| 15 | DELETE_MESSAGE | → `{"msg_id"}` |
+
+除 AUTH / HEARTBEAT / PUSH_ACK 外须先 AUTH，否则 `40102`。
+
+上线同步顺序：**先 `SYNC_INBOX`，再按会话 `SYNC_MESSAGES`**。游标是 Snowflake `MsgId` / inbox score，不是 ConversationSeq。
+
+Java / Swift 示例：`docs/clients/`，OpenAPI 里也可点开。
+
+---
+
+## 发消息路径
+
+必须按这个顺序（C5）：
+
+1. TaskPool（禁止在 EventLoop 里做）
+2. 权限（好友 / 拉黑 / 群禁言）——失败则不 INSERT
+3. Snowflake MsgId（或客户端 MsgId，须在 ±5 分钟内）
+4. MySQL 事务：消息表 + `conversations.last_msg_id`
+5. `DeliverQueue.Push`
+6. `SEND_ACK`
+
+第 5 步失败不 ACK。客户端用同一个 `client_msg_id` 重试。发送设备不回推 `MESSAGE`，其它设备必须推。同 `device_id` 顶旧连接，下发 `KICK`。
+
+私聊与群消息分表存储。消息类型 1–9：文本 / 图片 / 语音 / 视频 / 表情 / gif / 文件 / 位置 / 系统。`content` 是 JSON 序列化后的 **bytes**，不是字符串。
+
+---
+
+## 媒体 `object_key`
+
+客户端 **不自己拼 key**。`POST /v1/files` 只传 `purpose` / `mime` / `size`（群头像再加 `group_id`），服务端签发 Presigned PUT。PUT 必须原样带返回的 `headers`（`Content-Type`、`Content-Length`、`If-None-Match: *`）。同一 key 第二次 PUT 为 412。
+
+文件名是 **16 位 base62 随机串**（12 字节），不占用 Snowflake。路径不含 uid。
+
+| purpose | object_key | 生命周期 |
+| --- | --- | --- |
+| `avatar` | `perm/avatar/{yyyyMMdd}/{name}.{ext}` | 永久 |
+| `group_avatar` | `perm/group/{群号}/{name}.{ext}` | 永久 |
+| `chat_image` | `chat/image/{yyyyMMdd}/{name}.{ext}` | 桶生命周期 |
+| `chat_voice` | `chat/voice/{yyyyMMdd}/{name}.{ext}` | 桶生命周期 |
+| `chat_video` | `chat/video/{yyyyMMdd}/{name}.{ext}` | 桶生命周期 |
+| `chat_gif` | `chat/gif/{yyyyMMdd}/{name}.{ext}` | 桶生命周期 |
+| `chat_file` | `chat/file/{yyyyMMdd}/{name}.{ext}` | 桶生命周期 |
+
+日期 UTC `yyyyMMdd`。`ext` 由 mime 映射，未知为 `bin`。收藏复制到 `perm/fav/{yyyyMMdd}/{name}.{ext}`。
+
+合法 key：以 `perm/` 或 `chat/` 开头；禁止 `..`、空白、`\`、前导 `/`；最长 512。
+
+发图片：客户端只 PUT 原图，再 `POST /v1/files/variants` 让服务端出缩略图和预览。消息里只存 key。
+
+进程访问 RustFS 用内网 `object_storage.endpoint`（Docker 里是 `rustfs:9000`），签给客户端的 URL 用 `public_endpoint`（`https://sparkr.wyrs365.com`）。
+
+---
+
+## 目录
+
+```text
+cmd/server                       进程入口
+cmd/migrate                      按序执行 migrations/*.sql
+configs/config.yaml              本机开发配置
+deploy/docker/                   生产镜像、compose、deploy.sh
+deploy/nginx/                    443 SNI（host/ 是这台 ECS 的 drop-in）
+docs/architecture-v3.md          架构全文
+docs/clients/                    TCP Java / Swift demo
+internal/bootstrap               读配置、接线、生命周期
+internal/transport/http          Gin；handler 只绑定
+internal/transport/tcp           gnet Frame + TaskPool
+internal/module/{biz}/entity     领域类型，无 I/O
+internal/module/{biz}/model      一张表一个 Go 文件（GORM + COMMENT）
+internal/module/{biz}/logic      一个功能一个文件，禁止 import model
+internal/pkg                     errs / i18n / reply / reqctx / validate
+internal/infrastructure          MySQL / Redis / Snowflake / zap / RustFS
+migrations/                      SQL，改完必须在本机跑 migrate
+```
+
+`logic` 不 import `model`。接线在 `internal/bootstrap`。表和列必须有 COMMENT。
+
+---
+
+## 本机开发
+
+需要：Go 1.26、MySQL 8、Redis。对象存储可空（上传接口会不可用）。
+
+```bash
+# 配置 configs/config.yaml（env: dev）
+make migrate          # 应用 migrations/*.sql
+make start            # go run ./cmd/server -config configs/config.yaml
+# 或
+make run              # 先编 bin/spark-server 再启动
+```
+
+覆盖配置：`make start CONFIG=path/to.yaml`。
+
+```bash
+make test
+make lint             # funlen 100，lll 240
+```
+
+探活：
+
+```bash
+curl -sS http://127.0.0.1:8080/healthz
+curl -sS http://127.0.0.1:8080/readyz
+```
+
+`env: prod`（或 `SPARK_ENV=prod`）会拒绝空 MySQL DSN、空 Redis、以及默认 JWT secret。
+
+改了 `migrations/*.sql` 后自己跑 `make migrate`，不要留给部署。
+
+---
+
+## 部署（ECS）
+
+`make deploy` → `deploy/docker/deploy.sh`。默认 `root@47.236.66.9`，密钥 `~/.ssh/spark-ecs`。
+
+主机目录：
+
+| 路径 | 内容 |
+| --- | --- |
+| `/data/spark-server/app` | 构建源码 |
+| `/data/spark-server/configs/config.yaml` | 运行配置（来自 `deploy/docker/config.docker.yaml`） |
+| `/data/spark-server/logs` | 进程日志 |
+| `/data/spark-server/images/spark-server.tar.gz` | `docker save` |
+
+容器加入已有 `shell_default` 网络（mysql / redis / rustfs）。发布：
+
+- `127.0.0.1:18080` → 容器 HTTP 8080
+- `127.0.0.1:9090` → 容器 gnet 9090
+
+Nginx drop-in：`deploy/nginx/host/`，安装脚本 `bash deploy/nginx/install-host.sh`。不要覆盖整份 `/etc/nginx/nginx.conf`。
+
+Snowflake `snowflake_worker_id` 每进程唯一。时钟回拨会拒绝发号。
+
+---
+
+## 日志与 ID
+
+- zap 控制台和/或滚动文件（`log.console` / `log.file`）。GORM SQL 走同一套 zap。
+- HTTP `request_id`：11 位 base62，响应体 + `X-Request-ID`。
+- 对象文件名：16 位 base62，与 Snowflake 号段分开。
+- Snowflake 只给 uid、MsgId、会话 id、收藏行 id 等业务主键。
+
+---
+
+## 相关文档
+
+| 文档 | 内容 |
+| --- | --- |
+| [docs/architecture-v3.md](docs/architecture-v3.md) | 架构全文 |
+| `GET /docs` | OpenAPI / Swagger |
+| `GET /docs/enums` | 可跳转枚举 |
+| `GET /docs/errors` | 信封错误码 |
+| [deploy/nginx/README.md](deploy/nginx/README.md) | 443 SNI |
+| `docs/clients/` | TCP 客户端示例 |
+| `.cursor/skills/spark-im-v3/` | 实现约定（给 Agent） |
+| `.golangci.yaml` | 代码规范 |
diff --git a/configs/config.yaml b/configs/config.yaml
index 89c7364..4ec5ff4 100644
--- a/configs/config.yaml
+++ b/configs/config.yaml
@@ -84,6 +84,7 @@ message:
 
 object_storage:
   endpoint: "47.236.66.9:9000"
+  public_endpoint: "https://sparkr.wyrs365.com"
   access_key: "rustfs_spark"
   secret_key: 'kWvGtYT/~q+35q;3dSI<^P!MH+bgrpBg'
   bucket: "spark"
diff --git a/deploy/docker/config.docker.yaml b/deploy/docker/config.docker.yaml
index 7ded671..2952694 100644
--- a/deploy/docker/config.docker.yaml
+++ b/deploy/docker/config.docker.yaml
@@ -84,6 +84,7 @@ message:
 
 object_storage:
   endpoint: "rustfs:9000"
+  public_endpoint: "https://sparkr.wyrs365.com"
   access_key: "rustfs_spark"
   secret_key: 'kWvGtYT/~q+35q;3dSI<^P!MH+bgrpBg'
   bucket: "spark"
diff --git a/deploy/docker/deploy.sh b/deploy/docker/deploy.sh
index 04c6afc..111b198 100755
--- a/deploy/docker/deploy.sh
+++ b/deploy/docker/deploy.sh
@@ -33,6 +33,6 @@ rsync -az --delete \
 "${SSH[@]}" "docker save spark-server:latest | gzip -c > $DATA/images/spark-server.tar.gz"
 "${SSH[@]}" "cd $REMOTE/deploy/docker && docker compose -f docker-compose.yaml up -d spark-server"
 "${SSH[@]}" "docker exec spark-server /usr/local/bin/spark-migrate -config /app/configs/config.yaml -dir /app/migrations"
-"${SSH[@]}" "cp $REMOTE/deploy/nginx/host/spark-sni.conf /etc/nginx/stream.d/spark-sni.conf && nginx -t && systemctl reload nginx"
+"${SSH[@]}" "cp $REMOTE/deploy/nginx/host/spark-sni.conf /etc/nginx/stream.d/spark-sni.conf && if [ -f /etc/letsencrypt/live/sparkr.wyrs365.com/fullchain.pem ]; then cp $REMOTE/deploy/nginx/host/sparkr.conf /etc/nginx/conf.d/sparkr.conf; fi && nginx -t && systemctl reload nginx"
 "${SSH[@]}" "docker ps --filter name=spark-server --format 'table {{.Names}}\t{{.Status}}\t{{.Ports}}'"
 "${SSH[@]}" "curl -fsS http://127.0.0.1:18080/healthz && echo && curl -fsS http://127.0.0.1:18080/readyz && echo"
diff --git a/deploy/nginx/README.md b/deploy/nginx/README.md
index 05b242a..15bfed2 100644
--- a/deploy/nginx/README.md
+++ b/deploy/nginx/README.md
@@ -6,6 +6,8 @@ gnet v2 has no native TLS. IM certificates live here, not in spark-server `tcp.t
 Client --TLS--> :443 ssl_preread
                   ├─ SNI sparkapi.wyrs365.com → 127.0.0.1:8443 (HTTP TLS)
                   │                              → proxy_pass http://127.0.0.1:18080 + X-Real-IP
+                  ├─ SNI sparkr.wyrs365.com   → 127.0.0.1:8443 (HTTP TLS)
+                  │                              → proxy_pass http://127.0.0.1:9000 RustFS S3
                   └─ SNI sparkim.wyrs365.com  → 127.0.0.1:19001 (IM TLS)
                                                → PROXY protocol → 127.0.0.1:9090 gnet
 ```
@@ -13,6 +15,7 @@ Client --TLS--> :443 ssl_preread
 On this ECS, `:443` is shared with other wyrs HTTPS sites. Do **not** replace `/etc/nginx/nginx.conf`. Drop-ins:
 
 - `host/sparkapi.conf` → `/etc/nginx/conf.d/`
+- `host/sparkr.conf` → `/etc/nginx/conf.d/` (RustFS S3; DNS A record `sparkr.wyrs365.com` → this host)
 - `host/spark-sni.conf` → `/etc/nginx/stream.d/`
 
 Existing `listen 443 ssl` vhosts move to `127.0.0.1:8443 ssl proxy_protocol` so SNI can take public 443. `00-spark-http.conf` sets `real_ip_header proxy_protocol` and `port_in_redirect off` so `$remote_addr` is the client and redirects stay on 443.
@@ -20,9 +23,10 @@ Existing `listen 443 ssl` vhosts move to `127.0.0.1:8443 ssl proxy_protocol` so
 spark-server (Docker):
 
 - HTTP `127.0.0.1:18080` → container `:8080`
-- TCP `127.0.0.1:9090` with `proxy_protocol: true` → container `:9090` (host `:9000` is rustfs S3)
+- TCP `127.0.0.1:9090` with `proxy_protocol: true` → container `:9090` (host `:9000` is rustfs S3; bind `127.0.0.1:9000`, not public)
 - Image / config / logs: `/data/spark-server/{images,configs,logs}`
 - Public security group: 443 only
+- Clients upload/download at `https://sparkr.wyrs365.com` (path-style). spark-server talks to `rustfs:9000` on the Docker network and signs URLs with `object_storage.public_endpoint`.
 
 ```bash
 bash deploy/nginx/install-host.sh
diff --git a/deploy/nginx/host/spark-acme.conf b/deploy/nginx/host/spark-acme.conf
index c33e359..c6e1e43 100644
--- a/deploy/nginx/host/spark-acme.conf
+++ b/deploy/nginx/host/spark-acme.conf
@@ -3,7 +3,7 @@
 server {
     listen 80;
     listen [::]:80;
-    server_name sparkapi.wyrs365.com sparkim.wyrs365.com;
+    server_name sparkapi.wyrs365.com sparkim.wyrs365.com sparkr.wyrs365.com;
 
     location /.well-known/acme-challenge/ {
         root /var/www/certbot;
diff --git a/deploy/nginx/host/spark-sni.conf b/deploy/nginx/host/spark-sni.conf
index 38cc23a..a23bc92 100644
--- a/deploy/nginx/host/spark-sni.conf
+++ b/deploy/nginx/host/spark-sni.conf
@@ -1,6 +1,6 @@
 # Spark IM + shared HTTPS on :443 (ssl_preread).
 # sparkim.wyrs365.com → IM TLS terminator → PROXY plaintext to gnet :9090
-# default SNI → existing HTTP sites on 127.0.0.1:8443 (proxy_protocol restores RealIP)
+# default SNI → 127.0.0.1:8443 HTTP TLS (sparkapi / sparkr / other wyrs sites; PROXY restores RealIP)
 
 map $ssl_preread_server_name $spark_sni_backend {
     sparkim.wyrs365.com  127.0.0.1:19001;
diff --git a/deploy/nginx/host/sparkr.conf b/deploy/nginx/host/sparkr.conf
new file mode 100644
index 0000000..fe24bac
--- /dev/null
+++ b/deploy/nginx/host/sparkr.conf
@@ -0,0 +1,58 @@
+# Spark RustFS S3 — sparkr.wyrs365.com
+# Public :443 is stream ssl_preread (see stream.d/spark-sni.conf).
+# TLS terminates on loopback :8443; proxy HTTP to Docker rustfs on :9000.
+# Do not rewrite the URI: SigV4 signs host + path.
+
+upstream spark_rustfs {
+    server 127.0.0.1:9000;
+    keepalive 32;
+}
+
+server {
+    listen 80;
+    listen [::]:80;
+    server_name sparkr.wyrs365.com;
+
+    location /.well-known/acme-challenge/ {
+        root /var/www/certbot;
+    }
+
+    location / {
+        return 301 https://$host$request_uri;
+    }
+}
+
+server {
+    listen 127.0.0.1:8443 ssl proxy_protocol;
+    listen [::1]:8443 ssl proxy_protocol;
+    http2 on;
+    server_name sparkr.wyrs365.com;
+
+    ssl_certificate     /etc/letsencrypt/live/sparkr.wyrs365.com/fullchain.pem;
+    ssl_certificate_key /etc/letsencrypt/live/sparkr.wyrs365.com/privkey.pem;
+    ssl_session_timeout 1d;
+    ssl_session_cache shared:SparkSSL:10m;
+
+    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
+    add_header X-Content-Type-Options nosniff always;
+
+    ignore_invalid_headers off;
+    client_max_body_size 100m;
+    proxy_buffering off;
+    proxy_request_buffering off;
+    proxy_connect_timeout 300s;
+    proxy_send_timeout 300s;
+    proxy_read_timeout 300s;
+    proxy_http_version 1.1;
+    chunked_transfer_encoding off;
+
+    location / {
+        proxy_pass http://spark_rustfs;
+        proxy_set_header Host $http_host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto https;
+        proxy_set_header Connection "";
+        proxy_cache_convert_head off;
+    }
+}
diff --git a/deploy/nginx/install-host.sh b/deploy/nginx/install-host.sh
index 51a9371..3fa2732 100755
--- a/deploy/nginx/install-host.sh
+++ b/deploy/nginx/install-host.sh
@@ -5,33 +5,61 @@ set -euo pipefail
 ROOT="$(cd "$(dirname "$0")" && pwd)"
 HOST_DIR="$ROOT/host"
 BACKUP="/root/nginx-backup-$(date +%Y%m%d%H%M%S)"
+DOMAINS=(sparkapi.wyrs365.com sparkim.wyrs365.com sparkr.wyrs365.com)
 
-need_certs() {
-  [[ -f /etc/letsencrypt/live/sparkapi.wyrs365.com/fullchain.pem ]] \
-    && [[ -f /etc/letsencrypt/live/sparkim.wyrs365.com/fullchain.pem ]]
+cert_ok() {
+  [[ -f "/etc/letsencrypt/live/$1/fullchain.pem" ]]
 }
 
-install_acme() {
+all_certs_ok() {
+  local d
+  for d in "${DOMAINS[@]}"; do
+    cert_ok "$d" || return 1
+  done
+}
+
+install_acme_domain() {
+  local d=$1
   mkdir -p /var/www/certbot
-  cp "$HOST_DIR/spark-acme.conf" /etc/nginx/conf.d/spark-acme.conf
+  cat > "/etc/nginx/conf.d/spark-acme-${d}.conf" <<EOF
+server {
+    listen 80;
+    listen [::]:80;
+    server_name ${d};
+
+    location /.well-known/acme-challenge/ {
+        root /var/www/certbot;
+    }
+
+    location / {
+        return 404;
+    }
+}
+EOF
   nginx -t
   systemctl reload nginx
 }
 
-issue_certs() {
-  certbot certonly --webroot -w /var/www/certbot \
-    --non-interactive --agree-tos --keep-until-expiring \
-    -d sparkapi.wyrs365.com
-  certbot certonly --webroot -w /var/www/certbot \
-    --non-interactive --agree-tos --keep-until-expiring \
-    -d sparkim.wyrs365.com
+issue_missing_certs() {
+  local d
+  for d in "${DOMAINS[@]}"; do
+    if cert_ok "$d"; then
+      continue
+    fi
+    install_acme_domain "$d"
+    certbot certonly --webroot -w /var/www/certbot \
+      --non-interactive --agree-tos --keep-until-expiring \
+      -d "$d"
+    rm -f "/etc/nginx/conf.d/spark-acme-${d}.conf"
+  done
 }
 
 rewrite_http_443() {
   local f
   for f in /etc/nginx/conf.d/*.conf; do
     case "$(basename "$f")" in
-      sparkapi.conf|spark-acme.conf) continue ;;
+      sparkapi.conf|sparkr.conf|spark-acme.conf|00-spark-http.conf) continue ;;
+      spark-acme-*) continue ;;
     esac
     if grep -qE 'listen[[:space:]]+127\.0\.0\.1:8443' "$f"; then
       continue
@@ -48,8 +76,10 @@ rewrite_http_443() {
 install_sni() {
   rewrite_http_443
   rm -f /etc/nginx/conf.d/spark-acme.conf
+  rm -f /etc/nginx/conf.d/spark-acme-*.conf
   cp "$HOST_DIR/00-spark-http.conf" /etc/nginx/conf.d/00-spark-http.conf
   cp "$HOST_DIR/sparkapi.conf" /etc/nginx/conf.d/sparkapi.conf
+  cp "$HOST_DIR/sparkr.conf" /etc/nginx/conf.d/sparkr.conf
   cp "$HOST_DIR/spark-sni.conf" /etc/nginx/stream.d/spark-sni.conf
   mkdir -p /etc/letsencrypt/renewal-hooks/deploy
   cat > /etc/letsencrypt/renewal-hooks/deploy/reload-nginx.sh <<'HOOK'
@@ -69,12 +99,11 @@ mkdir -p "$BACKUP"
 cp -a /etc/nginx "$BACKUP/nginx"
 echo "backup $BACKUP"
 
-if ! need_certs; then
-  install_acme
-  issue_certs
+if ! all_certs_ok; then
+  issue_missing_certs
 fi
 
-if ! need_certs; then
+if ! all_certs_ok; then
   echo "certificates missing" >&2
   exit 1
 fi
diff --git a/internal/bootstrap/app.go b/internal/bootstrap/app.go
index 4d7892b..b110fdf 100644
--- a/internal/bootstrap/app.go
+++ b/internal/bootstrap/app.go
@@ -138,6 +138,7 @@ func finishApp(cfg *Config, log *zap.Logger, logClose func() error, idgen *id.Ge
 	authLimit := ratelimit.New(cfg.RateLimit.AuthPerSecond)
 	objects, err := objectstore.Open(&objectstore.Options{
 		Endpoint:       cfg.ObjectStorage.Endpoint,
+		PublicEndpoint: cfg.ObjectStorage.PublicEndpoint,
 		AccessKey:      cfg.ObjectStorage.AccessKey,
 		SecretKey:      cfg.ObjectStorage.SecretKey,
 		Bucket:         cfg.ObjectStorage.Bucket,
@@ -166,7 +167,7 @@ func finishApp(cfg *Config, log *zap.Logger, logClose func() error, idgen *id.Ge
 	friends := wireFriends(idgen, db, users, deliverQueue, chat)
 	groups := wireGroups(idgen, db, users, friends, deliverQueue, objects, chat)
 	messages := wireMessages(idgen, friends, groups, deliverQueue, chat)
-	files := wireFiles(cfg, objects, idgen, groups)
+	files := wireFiles(cfg, objects, groups)
 	favorites := wireFavorites(idgen, db, objects, chat)
 	app.tcp = tcp.NewServer(log, pool, sessions, &tcp.Options{
 		Addr:          cfg.Server.TCP.Addr,
@@ -276,11 +277,11 @@ func wireGroups(idgen *id.Generator, db *mysql.DB, users *userlogic.Service, fri
 	return grouplogic.NewService(repo, users, friends, idgen, chat.msgs, q, objects)
 }
 
-func wireFiles(cfg *Config, store *objectstore.Store, idgen *id.Generator, groups *grouplogic.Service) *uploadlogic.Service {
-	if store == nil || !store.Ready() || idgen == nil {
+func wireFiles(cfg *Config, store *objectstore.Store, groups *grouplogic.Service) *uploadlogic.Service {
+	if store == nil || !store.Ready() {
 		return nil
 	}
-	return uploadlogic.NewService(store, idgen, uploadlogic.Options{
+	return uploadlogic.NewService(store, uploadlogic.Options{
 		TTL:    cfg.ObjectStorage.PresignTTL,
 		Limit:  ratelimit.New(cfg.RateLimit.UploadPerSecond),
 		Groups: groups,
diff --git a/internal/bootstrap/config.go b/internal/bootstrap/config.go
index fe88b35..e2e4d1b 100644
--- a/internal/bootstrap/config.go
+++ b/internal/bootstrap/config.go
@@ -118,6 +118,7 @@ type RateLimitConfig struct {
 
 type ObjectStorageConfig struct {
 	Endpoint       string        `yaml:"endpoint"`
+	PublicEndpoint string        `yaml:"public_endpoint"`
 	AccessKey      string        `yaml:"access_key"`
 	SecretKey      string        `yaml:"secret_key"`
 	Bucket         string        `yaml:"bucket"`
@@ -229,6 +230,9 @@ func applyDefaults(cfg *Config) {
 	if v := os.Getenv("SPARK_S3_ENDPOINT"); v != "" {
 		cfg.ObjectStorage.Endpoint = v
 	}
+	if v := os.Getenv("SPARK_S3_PUBLIC_ENDPOINT"); v != "" {
+		cfg.ObjectStorage.PublicEndpoint = v
+	}
 	if v := os.Getenv("SPARK_S3_ACCESS_KEY"); v != "" {
 		cfg.ObjectStorage.AccessKey = v
 	}
diff --git a/internal/infrastructure/objectstore/ops.go b/internal/infrastructure/objectstore/ops.go
index fc93ae6..02ca246 100644
--- a/internal/infrastructure/objectstore/ops.go
+++ b/internal/infrastructure/objectstore/ops.go
@@ -18,13 +18,24 @@ import (
 	"spark-server/internal/pkg/errs"
 )
 
-const maxObjectBytes = 4 << 20
+const (
+	maxGetBytes = 32 << 20
+	maxPutBytes = 4 << 20
+)
 
-func (s *Store) PresignPut(ctx context.Context, key, contentType string, ttl time.Duration) (string, error) {
+func (s *Store) PresignPut(ctx context.Context, key, contentType string, size int64, ttl time.Duration) (string, error) {
 	if !s.Ready() {
 		return "", errs.ErrAvailable
 	}
-	in := &s3.PutObjectInput{Bucket: aws.String(s.bucket), Key: aws.String(key)}
+	if size < 1 {
+		return "", errs.ErrInvalidArgument
+	}
+	in := &s3.PutObjectInput{
+		Bucket:        aws.String(s.bucket),
+		Key:           aws.String(key),
+		ContentLength: aws.Int64(size),
+		IfNoneMatch:   aws.String("*"),
+	}
 	if contentType != "" {
 		in.ContentType = aws.String(contentType)
 	}
@@ -61,11 +72,11 @@ func (s *Store) Get(ctx context.Context, key string) ([]byte, error) {
 		return nil, mapObjectErr(err)
 	}
 	defer func() { _ = out.Body.Close() }()
-	data, err := io.ReadAll(io.LimitReader(out.Body, maxObjectBytes+1))
+	data, err := io.ReadAll(io.LimitReader(out.Body, maxGetBytes+1))
 	if err != nil {
 		return nil, mapObjectErr(err)
 	}
-	if len(data) > maxObjectBytes {
+	if len(data) > maxGetBytes {
 		return nil, errs.ErrInvalidArgument
 	}
 	return data, nil
@@ -75,7 +86,7 @@ func (s *Store) Put(ctx context.Context, key string, body []byte, contentType st
 	if !s.Ready() {
 		return errs.ErrAvailable
 	}
-	if len(body) == 0 || len(body) > maxObjectBytes {
+	if len(body) == 0 || len(body) > maxPutBytes {
 		return errs.ErrInvalidArgument
 	}
 	in := &s3.PutObjectInput{
diff --git a/internal/infrastructure/objectstore/store.go b/internal/infrastructure/objectstore/store.go
index 31310d7..63b9ce3 100644
--- a/internal/infrastructure/objectstore/store.go
+++ b/internal/infrastructure/objectstore/store.go
@@ -29,6 +29,7 @@ type Store struct {
 // Options configure Open. Empty Endpoint skips the connection.
 type Options struct {
 	Endpoint       string
+	PublicEndpoint string
 	AccessKey      string
 	SecretKey      string
 	Bucket         string
@@ -42,7 +43,7 @@ func Open(o *Options) (*Store, error) {
 	if o == nil || strings.TrimSpace(o.Endpoint) == "" {
 		return &Store{}, nil
 	}
-	host, secure, err := parseEndpoint(o.Endpoint, o.UseSSL)
+	client, presignBase, err := newClients(o)
 	if err != nil {
 		return nil, err
 	}
@@ -50,19 +51,14 @@ func Open(o *Options) (*Store, error) {
 	if bucket == "" {
 		bucket = "spark"
 	}
+	s := &Store{client: client, presign: s3.NewPresignClient(presignBase), bucket: bucket, log: o.Log}
+	if s.log == nil {
+		s.log = zap.NewNop()
+	}
 	region := strings.TrimSpace(o.Region)
 	if region == "" {
 		region = defaultRegion
 	}
-	scheme := "http"
-	if secure {
-		scheme = "https"
-	}
-	client := newS3Client(region, scheme+"://"+host, o.AccessKey, o.SecretKey)
-	s := &Store{client: client, presign: s3.NewPresignClient(client), bucket: bucket, log: o.Log}
-	if s.log == nil {
-		s.log = zap.NewNop()
-	}
 	ctx, cancel := context.WithTimeout(context.Background(), defaultTimeout)
 	defer cancel()
 	if err := s.ensureBucket(ctx, region, o.ChatExpireDays); err != nil {
@@ -83,6 +79,26 @@ func (s *Store) Ping(ctx context.Context) error {
 	return err
 }
 
+func newClients(o *Options) (*s3.Client, *s3.Client, error) {
+	region := strings.TrimSpace(o.Region)
+	if region == "" {
+		region = defaultRegion
+	}
+	host, secure, err := parseEndpoint(o.Endpoint, o.UseSSL)
+	if err != nil {
+		return nil, nil, err
+	}
+	client := newS3Client(region, endpointURL(host, secure), o.AccessKey, o.SecretKey)
+	if pub := strings.TrimSpace(o.PublicEndpoint); pub != "" {
+		phost, psecure, err := parseEndpoint(pub, true)
+		if err != nil {
+			return nil, nil, err
+		}
+		return client, newS3Client(region, endpointURL(phost, psecure), o.AccessKey, o.SecretKey), nil
+	}
+	return client, client, nil
+}
+
 func newS3Client(region, baseURL, access, secret string) *s3.Client {
 	return s3.New(s3.Options{
 		Region:                     region,
@@ -94,8 +110,15 @@ func newS3Client(region, baseURL, access, secret string) *s3.Client {
 	})
 }
 
+func endpointURL(host string, secure bool) string {
+	if secure {
+		return "https://" + host
+	}
+	return "http://" + host
+}
+
 func parseEndpoint(raw string, useSSL bool) (host string, secure bool, err error) {
-	raw = strings.TrimSpace(raw)
+	raw = strings.TrimSpace(strings.TrimRight(raw, "/"))
 	switch {
 	case raw == "":
 		return "", false, fmt.Errorf("objectstore: empty endpoint")
diff --git a/internal/infrastructure/objectstore/store_test.go b/internal/infrastructure/objectstore/store_test.go
index 0adbc78..fc77a0b 100644
--- a/internal/infrastructure/objectstore/store_test.go
+++ b/internal/infrastructure/objectstore/store_test.go
@@ -40,13 +40,17 @@ func TestOpenEmpty(t *testing.T) {
 func TestPresignLocal(t *testing.T) {
 	client := newS3Client(defaultRegion, "http://127.0.0.1:9000", "ak", "sk")
 	s := &Store{client: client, presign: s3.NewPresignClient(client), bucket: "spark"}
-	u, err := s.PresignPut(t.Context(), "chat/a.jpg", "image/jpeg", time.Hour)
+	u, err := s.PresignPut(t.Context(), "chat/a.jpg", "image/jpeg", 1024, time.Hour)
 	if err != nil {
 		t.Fatal(err)
 	}
 	if !strings.Contains(u, "127.0.0.1:9000/spark/chat/a.jpg") {
 		t.Fatalf("%s", u)
 	}
+	signed := strings.ToLower(u)
+	if !strings.Contains(signed, "content-length") || !strings.Contains(signed, "if-none-match") {
+		t.Fatalf("unsigned size/overwrite headers: %s", u)
+	}
 	g, err := s.PresignGet(t.Context(), "perm/avatar/1.jpg", time.Minute)
 	if err != nil {
 		t.Fatal(err)
@@ -56,6 +60,37 @@ func TestPresignLocal(t *testing.T) {
 	}
 }
 
+func TestPresignPutRejectsZeroSize(t *testing.T) {
+	client := newS3Client(defaultRegion, "http://127.0.0.1:9000", "ak", "sk")
+	s := &Store{client: client, presign: s3.NewPresignClient(client), bucket: "spark"}
+	if _, err := s.PresignPut(t.Context(), "chat/a.jpg", "image/jpeg", 0, time.Hour); !errors.Is(err, errs.ErrInvalidArgument) {
+		t.Fatalf("%v", err)
+	}
+}
+
+func TestPresignPublicEndpoint(t *testing.T) {
+	internal, public, err := newClients(&Options{
+		Endpoint:       "http://rustfs:9000",
+		PublicEndpoint: "https://sparkr.wyrs365.com/",
+		AccessKey:      "ak",
+		SecretKey:      "sk",
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	s := &Store{client: internal, presign: s3.NewPresignClient(public), bucket: "spark"}
+	u, err := s.PresignPut(t.Context(), "chat/a.jpg", "image/jpeg", 1024, time.Hour)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(u, "https://sparkr.wyrs365.com/spark/chat/a.jpg") {
+		t.Fatalf("%s", u)
+	}
+	if strings.Contains(u, "rustfs:9000") {
+		t.Fatalf("internal host leaked: %s", u)
+	}
+}
+
 func TestGetPutNotReady(t *testing.T) {
 	s, err := Open(&Options{})
 	if err != nil {
diff --git a/internal/module/favorite/logic/copy.go b/internal/module/favorite/logic/copy.go
index a72df2a..90fab90 100644
--- a/internal/module/favorite/logic/copy.go
+++ b/internal/module/favorite/logic/copy.go
@@ -7,9 +7,10 @@ import (
 	msgentity "spark-server/internal/module/message/entity"
 	uploadentity "spark-server/internal/module/upload/entity"
 	"spark-server/internal/pkg/errs"
+	"spark-server/internal/pkg/reqctx"
 )
 
-func (s *Service) copyMedia(ctx context.Context, userID int64, payload *msgentity.Content) ([]string, error) {
+func (s *Service) copyMedia(ctx context.Context, payload *msgentity.Content) ([]string, error) {
 	keys := payload.ObjectKeys()
 	if len(keys) == 0 {
 		return nil, nil
@@ -24,12 +25,7 @@ func (s *Service) copyMedia(ctx context.Context, userID int64, payload *msgentit
 		if _, ok := mapping[src]; ok {
 			continue
 		}
-		objectID, err := s.ids.NextID()
-		if err != nil {
-			s.deleteKeys(ctx, copied)
-			return nil, err
-		}
-		dst := uploadentity.BuildFavKey(userID, objectID, day, uploadentity.ExtOfKey(src))
+		dst := uploadentity.BuildFavKey(reqctx.NewObjectName(), day, uploadentity.ExtOfKey(src))
 		if err := s.objects.Copy(ctx, src, dst); err != nil {
 			s.deleteKeys(ctx, copied)
 			return nil, err
diff --git a/internal/module/favorite/logic/create.go b/internal/module/favorite/logic/create.go
index 2c08c30..a0350ed 100644
--- a/internal/module/favorite/logic/create.go
+++ b/internal/module/favorite/logic/create.go
@@ -47,7 +47,7 @@ func (s *Service) Create(ctx context.Context, userID int64, in *CreateInput) (*I
 	if err != nil {
 		return nil, err
 	}
-	copied, err := s.copyMedia(ctx, userID, payload)
+	copied, err := s.copyMedia(ctx, payload)
 	if err != nil {
 		return nil, err
 	}
diff --git a/internal/module/favorite/logic/favorite_test.go b/internal/module/favorite/logic/favorite_test.go
index 970cfd5..a57df9f 100644
--- a/internal/module/favorite/logic/favorite_test.go
+++ b/internal/module/favorite/logic/favorite_test.go
@@ -56,8 +56,12 @@ func TestFavoriteCopiesMediaAndExpires(t *testing.T) {
 		t.Fatal(err)
 	}
 	src := "chat/20260917/1/99.jpg"
+	thumb := "chat/20260917/1/t.jpg"
+	orig := "chat/20260917/1/o.jpg"
 	objs.keys[src] = true
-	raw, err := msgentity.NewImage(&msgentity.Image{Key: src, Mime: "image/jpeg"}).Marshal()
+	objs.keys[thumb] = true
+	objs.keys[orig] = true
+	raw, err := msgentity.NewImage(&msgentity.Image{Key: src, ThumbKey: thumb, OrigKey: orig, Mime: "image/jpeg"}).Marshal()
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -76,10 +80,10 @@ func TestFavoriteCopiesMediaAndExpires(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if item.MsgID != msgID || !strings.Contains(string(item.Content), "perm/fav/1/") {
+	if item.MsgID != msgID || !strings.Contains(string(item.Content), "perm/fav/") {
 		t.Fatalf("%+v", item)
 	}
-	if strings.Contains(string(item.Content), src) {
+	if strings.Contains(string(item.Content), src) || strings.Contains(string(item.Content), orig) {
 		t.Fatal("still points at chat key")
 	}
 	again, err := svc.Create(ctx, 1, &CreateInput{MsgID: msgID})
diff --git a/internal/module/group/logic/avatar.go b/internal/module/group/logic/avatar.go
index 105826e..57159cc 100644
--- a/internal/module/group/logic/avatar.go
+++ b/internal/module/group/logic/avatar.go
@@ -13,6 +13,7 @@ import (
 	"spark-server/internal/module/group/entity"
 	uploadentity "spark-server/internal/module/upload/entity"
 	userentity "spark-server/internal/module/user/entity"
+	"spark-server/internal/pkg/reqctx"
 )
 
 const collageJPEG = "image/jpeg"
@@ -63,10 +64,7 @@ func (s *Service) putAvatar(ctx context.Context, g *entity.Group, raw []byte, mi
 	if g == nil || len(raw) == 0 {
 		return false
 	}
-	key := uploadentity.PrefixGroup + strconv.FormatInt(g.ID, 10) + "/default." + ext
-	if objectID, err := s.ids.NextID(); err == nil {
-		key = uploadentity.BuildObjectKey(uploadentity.PurposeGroupAvatar, g.ID, objectID, "", ext)
-	}
+	key := uploadentity.BuildObjectKey(uploadentity.PurposeGroupAvatar, g.ID, reqctx.NewObjectName(), "", ext)
 	if err := s.objects.Put(ctx, key, raw, mime); err != nil {
 		return false
 	}
diff --git a/internal/module/message/entity/content.go b/internal/module/message/entity/content.go
index d3bf3be..6ff51be 100644
--- a/internal/module/message/entity/content.go
+++ b/internal/module/message/entity/content.go
@@ -121,7 +121,7 @@ func (c *Content) Validate() error {
 	case TypeText:
 		return validateText(c.Text)
 	case TypeImage:
-		return validateMediaKey("image", c.Image.Key)
+		return validateImage(c.Image)
 	case TypeVoice:
 		return validateVoice(c.Voice)
 	case TypeVideo:
@@ -220,6 +220,16 @@ func validateMentions(c *Content) error {
 	return nil
 }
 
+func validateImage(img *Image) error {
+	if err := validateMediaKey("image", img.Key); err != nil {
+		return err
+	}
+	if img.Size < 0 || img.OrigSize < 0 || img.Width < 0 || img.Height < 0 || img.OrigW < 0 || img.OrigH < 0 {
+		return fmt.Errorf("content: image size")
+	}
+	return nil
+}
+
 func validateMediaKey(kind, key string) error {
 	if strings.TrimSpace(key) == "" {
 		return fmt.Errorf("content: %s key empty", kind)
@@ -279,14 +289,21 @@ func (c *Content) ObjectKeys() []string {
 	var keys []string
 	add := func(k string) {
 		k = strings.TrimSpace(k)
-		if k != "" {
-			keys = append(keys, k)
+		if k == "" {
+			return
 		}
+		for _, existing := range keys {
+			if existing == k {
+				return
+			}
+		}
+		keys = append(keys, k)
 	}
 	switch {
 	case c.Image != nil:
 		add(c.Image.Key)
 		add(c.Image.ThumbKey)
+		add(c.Image.OrigKey)
 	case c.Voice != nil:
 		add(c.Voice.Key)
 	case c.Video != nil:
@@ -316,6 +333,7 @@ func (c *Content) ReplaceObjectKeys(mapping map[string]string) {
 	if c.Image != nil {
 		repl(&c.Image.Key)
 		repl(&c.Image.ThumbKey)
+		repl(&c.Image.OrigKey)
 	}
 	if c.Voice != nil {
 		repl(&c.Voice.Key)
diff --git a/internal/module/message/entity/content_test.go b/internal/module/message/entity/content_test.go
index 283d5ba..ab43b37 100644
--- a/internal/module/message/entity/content_test.go
+++ b/internal/module/message/entity/content_test.go
@@ -80,6 +80,9 @@ func TestRejectsRawStringAndEmptyKey(t *testing.T) {
 	if _, err := NewImage(&Image{}).Marshal(); err == nil || !strings.Contains(err.Error(), "key") {
 		t.Fatalf("image key: %v", err)
 	}
+	if _, err := NewImage(&Image{Key: "k", OrigSize: -1}).Marshal(); err == nil {
+		t.Fatal("negative orig_size")
+	}
 	bad := &Content{Type: TypeText, Text: &Text{Body: "x"}, Image: &Image{Key: "k"}}
 	if _, err := bad.Marshal(); err == nil {
 		t.Fatal("two payloads")
@@ -122,13 +125,21 @@ func TestMentionsRoundTrip(t *testing.T) {
 }
 
 func TestObjectKeysAndReplace(t *testing.T) {
-	img := NewImage(&Image{Key: "chat/a.jpg", ThumbKey: "chat/t.jpg"})
+	img := NewImage(&Image{Key: "chat/a.jpg", ThumbKey: "chat/t.jpg", OrigKey: "chat/o.jpg", OrigSize: 4 << 20})
 	keys := img.ObjectKeys()
-	if len(keys) != 2 || keys[0] != "chat/a.jpg" {
+	if len(keys) != 3 || keys[0] != "chat/a.jpg" || keys[2] != "chat/o.jpg" {
 		t.Fatalf("%v", keys)
 	}
-	img.ReplaceObjectKeys(map[string]string{"chat/a.jpg": "perm/fav/1/x.jpg", "chat/t.jpg": "perm/fav/1/y.jpg"})
-	if img.Image.Key != "perm/fav/1/x.jpg" || img.Image.ThumbKey != "perm/fav/1/y.jpg" {
+	img.ReplaceObjectKeys(map[string]string{
+		"chat/a.jpg": "perm/fav/1/x.jpg",
+		"chat/t.jpg": "perm/fav/1/y.jpg",
+		"chat/o.jpg": "perm/fav/1/z.jpg",
+	})
+	if img.Image.Key != "perm/fav/1/x.jpg" || img.Image.ThumbKey != "perm/fav/1/y.jpg" || img.Image.OrigKey != "perm/fav/1/z.jpg" {
 		t.Fatalf("%+v", img.Image)
 	}
+	same := NewImage(&Image{Key: "chat/a.jpg", OrigKey: "chat/a.jpg"})
+	if got := same.ObjectKeys(); len(got) != 1 {
+		t.Fatalf("dedupe %v", got)
+	}
 }
diff --git a/internal/module/message/entity/payload.go b/internal/module/message/entity/payload.go
index d987e27..6e52782 100644
--- a/internal/module/message/entity/payload.go
+++ b/internal/module/message/entity/payload.go
@@ -5,7 +5,10 @@ type Text struct {
 	Body string `json:"body"`
 }
 
-// Image references an uploaded object. Bytes themselves are not stored in messages.content.
+// Image references uploaded objects. Bytes are not stored in messages.content.
+// WeChat-style: bubble uses thumb_key, tap-to-view uses key (compressed),
+// 「查看原图」uses orig_key when the sender opted in.
+// Clients PUT JPEG/PNG only (convert HEIC/WebP locally); the server does not transcode.
 type Image struct {
 	Key      string `json:"key"`
 	Mime     string `json:"mime,omitempty"`
@@ -13,6 +16,10 @@ type Image struct {
 	Height   int    `json:"h,omitempty"`
 	Size     int64  `json:"size,omitempty"`
 	ThumbKey string `json:"thumb_key,omitempty"`
+	OrigKey  string `json:"orig_key,omitempty"`
+	OrigSize int64  `json:"orig_size,omitempty"`
+	OrigW    int    `json:"orig_w,omitempty"`
+	OrigH    int    `json:"orig_h,omitempty"`
 }
 
 // Voice is an audio clip in object storage.
diff --git a/internal/module/upload/entity/credential.go b/internal/module/upload/entity/credential.go
index 90ed80f..3e9604b 100644
--- a/internal/module/upload/entity/credential.go
+++ b/internal/module/upload/entity/credential.go
@@ -9,6 +9,11 @@ type Credential struct {
 	ExpiresIn int64             `json:"expires_in"`
 }
 
+// CredentialSet is one HTTP round-trip for up to three PUTs (thumb / preview / orig).
+type CredentialSet struct {
+	Items []Credential `json:"items"`
+}
+
 type Download struct {
 	ObjectKey   string `json:"object_key"`
 	DownloadURL string `json:"download_url"`
diff --git a/internal/module/upload/entity/purpose.go b/internal/module/upload/entity/purpose.go
index c30a9ab..a86c511 100644
--- a/internal/module/upload/entity/purpose.go
+++ b/internal/module/upload/entity/purpose.go
@@ -16,11 +16,16 @@ const (
 	PurposeChatGIF     = "chat_gif"
 	PurposeChatFile    = "chat_file"
 
-	PrefixPerm   = "perm/"
-	PrefixChat   = "chat/"
-	PrefixAvatar = "perm/avatar/"
-	PrefixGroup  = "perm/group/"
-	PrefixFav    = "perm/fav/"
+	PrefixPerm      = "perm/"
+	PrefixChat      = "chat/"
+	PrefixAvatar    = "perm/avatar/"
+	PrefixGroup     = "perm/group/"
+	PrefixFav       = "perm/fav/"
+	PrefixChatImage = "chat/image/"
+	PrefixChatVoice = "chat/voice/"
+	PrefixChatVideo = "chat/video/"
+	PrefixChatGIF   = "chat/gif/"
+	PrefixChatFile  = "chat/file/"
 
 	MethodPUT = "PUT"
 	MethodGET = "GET"
@@ -28,7 +33,8 @@ const (
 
 const (
 	maxAvatar  = 2 << 20
-	maxImage   = 10 << 20
+	maxImage   = 32 << 20
+	maxGIF     = 10 << 20
 	maxVoice   = 16 << 20
 	maxVideo   = 100 << 20
 	maxFile    = 50 << 20
@@ -75,25 +81,46 @@ func ExtOfKey(key string) string {
 	return ext
 }
 
-func BuildObjectKey(purpose string, ownerID, objectID int64, day, ext string) string {
+func BuildObjectKey(purpose string, ownerID int64, name, day, ext string) string {
 	if ext == "" {
 		ext = extDefault
 	}
+	if name == "" {
+		name = "0"
+	}
 	switch purpose {
 	case PurposeAvatar:
-		return fmt.Sprintf("%s%d/%s/%d.%s", PrefixAvatar, ownerID, day, objectID, ext)
+		return fmt.Sprintf("%s%s/%s.%s", PrefixAvatar, day, name, ext)
 	case PurposeGroupAvatar:
-		return fmt.Sprintf("%s%d/%d.%s", PrefixGroup, ownerID, objectID, ext)
+		return fmt.Sprintf("%s%d/%s.%s", PrefixGroup, ownerID, name, ext)
 	default:
-		return fmt.Sprintf("%s%s/%d/%d.%s", PrefixChat, day, ownerID, objectID, ext)
+		return fmt.Sprintf("%s%s/%s/%s.%s", PrefixChat, chatKind(purpose), day, name, ext)
 	}
 }
 
-func BuildFavKey(userID, objectID int64, day, ext string) string {
+func BuildFavKey(name, day, ext string) string {
 	if ext == "" {
 		ext = extDefault
 	}
-	return fmt.Sprintf("%s%d/%s/%d.%s", PrefixFav, userID, day, objectID, ext)
+	if name == "" {
+		name = "0"
+	}
+	return fmt.Sprintf("%s%s/%s.%s", PrefixFav, day, name, ext)
+}
+
+func chatKind(purpose string) string {
+	switch purpose {
+	case PurposeChatImage:
+		return "image"
+	case PurposeChatVoice:
+		return "voice"
+	case PurposeChatVideo:
+		return "video"
+	case PurposeChatGIF:
+		return "gif"
+	default:
+		return "file"
+	}
 }
 
 func ValidObjectKey(key string) bool {
@@ -110,13 +137,13 @@ var specs = map[string]Spec{
 	PurposeAvatar:      {Purpose: PurposeAvatar, MaxSize: maxAvatar, MIMEs: imageMIMEs},
 	PurposeGroupAvatar: {Purpose: PurposeGroupAvatar, MaxSize: maxAvatar, MIMEs: imageMIMEs},
 	PurposeChatImage:   {Purpose: PurposeChatImage, MaxSize: maxImage, MIMEs: imageMIMEs},
-	PurposeChatGIF:     {Purpose: PurposeChatGIF, MaxSize: maxImage, MIMEs: gifMIMEs},
+	PurposeChatGIF:     {Purpose: PurposeChatGIF, MaxSize: maxGIF, MIMEs: gifMIMEs},
 	PurposeChatVoice:   {Purpose: PurposeChatVoice, MaxSize: maxVoice, MIMEs: voiceMIMEs},
 	PurposeChatVideo:   {Purpose: PurposeChatVideo, MaxSize: maxVideo, MIMEs: videoMIMEs},
 	PurposeChatFile:    {Purpose: PurposeChatFile, MaxSize: maxFile, MIMEs: fileMIMEs},
 }
 
-var imageMIMEs = set("image/jpeg", "image/jpg", "image/png", "image/webp", "image/heic", "image/heif")
+var imageMIMEs = set("image/jpeg", "image/jpg", "image/png")
 var gifMIMEs = set("image/gif", "image/webp")
 var voiceMIMEs = set("audio/mpeg", "audio/mp4", "audio/aac", "audio/amr", "audio/ogg", "audio/wav", "audio/webm", "audio/x-m4a")
 var videoMIMEs = set("video/mp4", "video/quicktime", "video/webm")
@@ -129,7 +156,7 @@ var fileMIMEs = set(
 
 var mimeExt = map[string]string{
 	"image/jpeg": "jpg", "image/jpg": "jpg", "image/png": "png", "image/webp": "webp",
-	"image/heic": "heic", "image/heif": "heif", "image/gif": "gif",
+	"image/gif": "gif",
 	"audio/mpeg": "mp3", "audio/mp4": "m4a", "audio/aac": "aac", "audio/amr": "amr",
 	"audio/ogg": "ogg", "audio/wav": "wav", "audio/webm": "weba", "audio/x-m4a": "m4a",
 	"video/mp4": "mp4", "video/quicktime": "mov", "video/webm": "webm",
diff --git a/internal/module/upload/entity/purpose_test.go b/internal/module/upload/entity/purpose_test.go
index 71830a4..935b635 100644
--- a/internal/module/upload/entity/purpose_test.go
+++ b/internal/module/upload/entity/purpose_test.go
@@ -6,20 +6,24 @@ import (
 )
 
 func TestBuildObjectKeyByPurpose(t *testing.T) {
-	avatar := BuildObjectKey(PurposeAvatar, 11, 99, "20260917", "jpg")
-	if avatar != "perm/avatar/11/20260917/99.jpg" {
+	avatar := BuildObjectKey(PurposeAvatar, 11, "99", "20260917", "jpg")
+	if avatar != "perm/avatar/20260917/99.jpg" {
 		t.Fatalf("avatar %s", avatar)
 	}
-	chat := BuildObjectKey(PurposeChatImage, 11, 99, "20260917", "jpg")
-	if chat != "chat/20260917/11/99.jpg" {
+	chat := BuildObjectKey(PurposeChatImage, 11, "99", "20260917", "jpg")
+	if chat != "chat/image/20260917/99.jpg" {
 		t.Fatalf("chat %s", chat)
 	}
-	group := BuildObjectKey(PurposeGroupAvatar, 7, 99, "20260917", "png")
+	voice := BuildObjectKey(PurposeChatVoice, 11, "aa", "20260917", "m4a")
+	if voice != "chat/voice/20260917/aa.m4a" {
+		t.Fatalf("voice %s", voice)
+	}
+	group := BuildObjectKey(PurposeGroupAvatar, 7, "99", "20260917", "png")
 	if group != "perm/group/7/99.png" {
 		t.Fatalf("group %s", group)
 	}
-	fav := BuildFavKey(11, 7, "20260917", "m4a")
-	if fav != "perm/fav/11/20260917/7.m4a" {
+	fav := BuildFavKey("99", "20260917", "m4a")
+	if fav != "perm/fav/20260917/99.m4a" {
 		t.Fatalf("fav %s", fav)
 	}
 }
@@ -49,7 +53,19 @@ func TestNormalizeMIMEAndExt(t *testing.T) {
 	if _, ok := spec.MIMEs["audio/mpeg"]; !ok {
 		t.Fatal("voice mime")
 	}
-	if strings.Contains(BuildObjectKey(PurposeAvatar, 1, 1, "d", "jpg"), PrefixChat) {
+	img, ok := LookupSpec(PurposeChatImage)
+	if !ok {
+		t.Fatal("image spec")
+	}
+	if _, ok := img.MIMEs["image/jpeg"]; !ok {
+		t.Fatal("jpeg")
+	}
+	for _, mime := range []string{"image/heic", "image/heif", "image/webp"} {
+		if _, ok := img.MIMEs[mime]; ok {
+			t.Fatalf("interchange must not allow %s", mime)
+		}
+	}
+	if strings.Contains(BuildObjectKey(PurposeAvatar, 1, "1", "d", "jpg"), PrefixChat) {
 		t.Fatal("avatar must be perm")
 	}
 }
diff --git a/internal/module/upload/logic/batch.go b/internal/module/upload/logic/batch.go
new file mode 100644
index 0000000..a506280
--- /dev/null
+++ b/internal/module/upload/logic/batch.go
@@ -0,0 +1,49 @@
+package logic
+
+import (
+	"context"
+
+	"spark-server/internal/module/upload/entity"
+	"spark-server/internal/pkg/errs"
+	"spark-server/internal/pkg/reqctx"
+	"spark-server/internal/pkg/validate"
+)
+
+const maxCredentialBatch = 3
+
+// BatchCreateInput issues up to three Presigned PUTs in one call (thumb / preview / orig).
+type BatchCreateInput struct {
+	Items []CreateInput `json:"items" validate:"required,min=1,max=3,dive" label:"field.upload_items" errmsg:"required:validate.upload.items_required;min:validate.upload.items_required;max:validate.upload.items_invalid"`
+}
+
+func (s *Service) CreateCredentials(ctx context.Context, userID int64, in *BatchCreateInput) (*entity.CredentialSet, error) {
+	if !s.ready() {
+		return nil, errs.ErrAvailable
+	}
+	if userID <= 0 {
+		return nil, errs.ErrUnauthorized
+	}
+	if in == nil {
+		return nil, errs.ErrInvalidArgument
+	}
+	if err := validate.StructLang(reqctx.Lang(ctx), in); err != nil {
+		return nil, err
+	}
+	if n := len(in.Items); n < 1 || n > maxCredentialBatch {
+		return nil, errs.ErrInvalidArgument
+	}
+	for range in.Items {
+		if !s.allow(userID) {
+			return nil, errs.ErrRateLimited
+		}
+	}
+	items := make([]entity.Credential, 0, len(in.Items))
+	for i := range in.Items {
+		cred, err := s.issuePut(ctx, userID, &in.Items[i])
+		if err != nil {
+			return nil, err
+		}
+		items = append(items, *cred)
+	}
+	return &entity.CredentialSet{Items: items}, nil
+}
diff --git a/internal/module/upload/logic/credential.go b/internal/module/upload/logic/credential.go
index 590667e..6ea7ed7 100644
--- a/internal/module/upload/logic/credential.go
+++ b/internal/module/upload/logic/credential.go
@@ -2,6 +2,7 @@ package logic
 
 import (
 	"context"
+	"strconv"
 
 	"spark-server/internal/module/upload/entity"
 	"spark-server/internal/pkg/errs"
@@ -34,14 +35,15 @@ func (s *Service) CreateCredential(ctx context.Context, userID int64, in *Create
 	if !s.allow(userID) {
 		return nil, errs.ErrRateLimited
 	}
+	return s.issuePut(ctx, userID, in)
+}
+
+func (s *Service) issuePut(ctx context.Context, userID int64, in *CreateInput) (*entity.Credential, error) {
 	_, mime, err := matchSpec(ctx, in)
 	if err != nil {
 		return nil, err
 	}
-	objectID, err := s.ids.NextID()
-	if err != nil {
-		return nil, err
-	}
+	name := reqctx.NewObjectName()
 	ownerID := userID
 	if in.Purpose == entity.PurposeGroupAvatar {
 		if err := s.readyGroupAvatar(ctx, userID, in.GroupID); err != nil {
@@ -49,8 +51,8 @@ func (s *Service) CreateCredential(ctx context.Context, userID int64, in *Create
 		}
 		ownerID = in.GroupID
 	}
-	key := entity.BuildObjectKey(in.Purpose, ownerID, objectID, dayOf(s.now()), entity.ExtForMIME(mime))
-	url, err := s.store.PresignPut(ctx, key, mime, s.ttl)
+	key := entity.BuildObjectKey(in.Purpose, ownerID, name, dayOf(s.now()), entity.ExtForMIME(mime))
+	url, err := s.store.PresignPut(ctx, key, mime, in.Size, s.ttl)
 	if err != nil {
 		return nil, err
 	}
@@ -58,7 +60,11 @@ func (s *Service) CreateCredential(ctx context.Context, userID int64, in *Create
 		ObjectKey: key,
 		UploadURL: url,
 		Method:    entity.MethodPUT,
-		Headers:   map[string]string{"Content-Type": mime},
+		Headers: map[string]string{
+			"Content-Type":   mime,
+			"Content-Length": strconv.FormatInt(in.Size, 10),
+			"If-None-Match":  "*",
+		},
 		ExpiresIn: s.expiresIn(),
 	}, nil
 }
diff --git a/internal/module/upload/logic/credential_test.go b/internal/module/upload/logic/credential_test.go
index e09c11c..62a24c7 100644
--- a/internal/module/upload/logic/credential_test.go
+++ b/internal/module/upload/logic/credential_test.go
@@ -7,7 +7,6 @@ import (
 	"testing"
 	"time"
 
-	"spark-server/internal/infrastructure/id"
 	"spark-server/internal/module/upload/entity"
 	"spark-server/internal/pkg/errs"
 	"spark-server/internal/pkg/reqctx"
@@ -18,7 +17,7 @@ type fakeStore struct {
 	putErr   error
 }
 
-func (f *fakeStore) PresignPut(_ context.Context, key, _ string, _ time.Duration) (string, error) {
+func (f *fakeStore) PresignPut(_ context.Context, key, _ string, _ int64, _ time.Duration) (string, error) {
 	if f.putErr != nil {
 		return "", f.putErr
 	}
@@ -37,11 +36,7 @@ func (f *fakeStore) PresignGet(_ context.Context, key string, _ time.Duration) (
 
 func testUpload(t *testing.T) *Service {
 	t.Helper()
-	ids, err := id.New(1)
-	if err != nil {
-		t.Fatal(err)
-	}
-	return NewService(&fakeStore{}, ids, Options{
+	return NewService(&fakeStore{}, Options{
 		TTL: 5 * time.Minute,
 		Now: func() time.Time { return time.Date(2026, 9, 17, 8, 0, 0, 0, time.UTC) },
 	})
@@ -54,11 +49,13 @@ func TestCreateCredentialChatVsAvatar(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if !strings.HasPrefix(chat.ObjectKey, "chat/20260917/42/") || chat.Method != "PUT" || chat.Headers["Content-Type"] != "image/jpeg" {
+	if !strings.HasPrefix(chat.ObjectKey, "chat/image/20260917/") || chat.Method != "PUT" ||
+		chat.Headers["Content-Type"] != "image/jpeg" || chat.Headers["Content-Length"] != "1024" ||
+		chat.Headers["If-None-Match"] != "*" || strings.Contains(chat.ObjectKey, "/42/") {
 		t.Fatalf("%+v", chat)
 	}
 	avatar, err := svc.CreateCredential(ctx, 42, &CreateInput{Purpose: entity.PurposeAvatar, Mime: "image/png", Size: 2048})
-	if err != nil || !strings.HasPrefix(avatar.ObjectKey, "perm/avatar/42/20260917/") {
+	if err != nil || !strings.HasPrefix(avatar.ObjectKey, "perm/avatar/20260917/") {
 		t.Fatalf("%+v %v", avatar, err)
 	}
 	group, err := svc.CreateCredential(ctx, 42, &CreateInput{Purpose: entity.PurposeGroupAvatar, Mime: "image/jpeg", Size: 1024, GroupID: 7})
@@ -79,6 +76,11 @@ func TestCreateCredentialRejectsBadMIMEAndSize(t *testing.T) {
 	if _, err := svc.CreateCredential(ctx, 1, &CreateInput{Purpose: entity.PurposeChatImage, Mime: "image/jpeg", Size: 50 << 20}); err == nil {
 		t.Fatal("huge image")
 	}
+	for _, mime := range []string{"image/heic", "image/heif", "image/webp"} {
+		if _, err := svc.CreateCredential(ctx, 1, &CreateInput{Purpose: entity.PurposeChatImage, Mime: mime, Size: 1024}); err == nil {
+			t.Fatalf("accepted %s", mime)
+		}
+	}
 	if _, err := svc.CreateCredential(ctx, 0, &CreateInput{Purpose: entity.PurposeChatImage, Mime: "image/jpeg", Size: 1}); !errors.Is(err, errs.ErrUnauthorized) {
 		t.Fatalf("uid %v", err)
 	}
@@ -95,3 +97,24 @@ func TestCreateDownloadValidatesKey(t *testing.T) {
 		t.Fatal("path escape")
 	}
 }
+
+func TestCreateCredentialsBatch(t *testing.T) {
+	svc := testUpload(t)
+	ctx := reqctx.With(t.Context(), &reqctx.RequestContext{UserID: 42, Language: "zh-CN"})
+	part := func(size int64) CreateInput {
+		return CreateInput{Purpose: entity.PurposeChatImage, Mime: "image/jpeg", Size: size}
+	}
+	got, err := svc.CreateCredentials(ctx, 42, &BatchCreateInput{Items: []CreateInput{part(1024), part(2048), part(4096)}})
+	if err != nil || got == nil || len(got.Items) != 3 {
+		t.Fatalf("%+v %v", got, err)
+	}
+	if got.Items[0].ObjectKey == got.Items[1].ObjectKey || got.Items[1].Headers["Content-Length"] != "2048" {
+		t.Fatalf("%+v", got.Items)
+	}
+	if _, err := svc.CreateCredentials(ctx, 42, &BatchCreateInput{}); err == nil {
+		t.Fatal("empty")
+	}
+	if _, err := svc.CreateCredentials(ctx, 42, &BatchCreateInput{Items: []CreateInput{part(1), part(1), part(1), part(1)}}); err == nil {
+		t.Fatal("too many")
+	}
+}
diff --git a/internal/module/upload/logic/service.go b/internal/module/upload/logic/service.go
index 9a6983a..6c86b65 100644
--- a/internal/module/upload/logic/service.go
+++ b/internal/module/upload/logic/service.go
@@ -10,15 +10,10 @@ import (
 
 // Presigner issues short-lived object-storage URLs. Infrastructure implements it.
 type Presigner interface {
-	PresignPut(ctx context.Context, key, contentType string, ttl time.Duration) (string, error)
+	PresignPut(ctx context.Context, key, contentType string, size int64, ttl time.Duration) (string, error)
 	PresignGet(ctx context.Context, key string, ttl time.Duration) (string, error)
 }
 
-type IDGen interface {
-	NextID() (int64, error)
-}
-
-// AvatarACL gates group_avatar uploads. Nil skips the check (tests).
 type AvatarACL interface {
 	CanSetAvatar(ctx context.Context, userID, groupID int64) error
 }
@@ -33,14 +28,13 @@ type Options struct {
 // Service issues upload/download credentials. HTTP and TCP share it.
 type Service struct {
 	store  Presigner
-	ids    IDGen
 	ttl    time.Duration
 	limit  *ratelimit.Limiter
 	now    func() time.Time
 	groups AvatarACL
 }
 
-func NewService(store Presigner, ids IDGen, opt Options) *Service {
+func NewService(store Presigner, opt Options) *Service {
 	ttl := opt.TTL
 	if ttl <= 0 {
 		ttl = 15 * time.Minute
@@ -49,11 +43,11 @@ func NewService(store Presigner, ids IDGen, opt Options) *Service {
 	if clock == nil {
 		clock = func() time.Time { return time.Now().UTC() }
 	}
-	return &Service{store: store, ids: ids, ttl: ttl, limit: opt.Limit, now: clock, groups: opt.Groups}
+	return &Service{store: store, ttl: ttl, limit: opt.Limit, now: clock, groups: opt.Groups}
 }
 
 func (s *Service) ready() bool {
-	return s != nil && s.store != nil && s.ids != nil
+	return s != nil && s.store != nil
 }
 
 func (s *Service) expiresIn() int64 {
diff --git a/internal/module/user/logic/avatar.go b/internal/module/user/logic/avatar.go
index ee02231..9a4abe9 100644
--- a/internal/module/user/logic/avatar.go
+++ b/internal/module/user/logic/avatar.go
@@ -7,6 +7,7 @@ import (
 
 	uploadentity "spark-server/internal/module/upload/entity"
 	"spark-server/internal/module/user/entity"
+	"spark-server/internal/pkg/reqctx"
 )
 
 const defaultAvatarMIME = "image/png"
@@ -42,18 +43,14 @@ func (s *Service) stampDefaultAvatar(ctx context.Context, u *entity.User) {
 }
 
 func (s *Service) putLetterPNG(ctx context.Context, u *entity.User) string {
-	if s == nil || s.objects == nil || s.ids == nil || u == nil || u.ID <= 0 {
+	if s == nil || s.objects == nil || u == nil || u.ID <= 0 {
 		return ""
 	}
 	raw, err := entity.LetterAvatarPNG(u.Nickname)
 	if err != nil || len(raw) == 0 {
 		return ""
 	}
-	objectID, err := s.ids.NextID()
-	if err != nil {
-		return ""
-	}
-	key := uploadentity.BuildObjectKey(uploadentity.PurposeAvatar, u.ID, objectID, time.Now().Format("20060102"), "png")
+	key := uploadentity.BuildObjectKey(uploadentity.PurposeAvatar, u.ID, reqctx.NewObjectName(), time.Now().UTC().Format("20060102"), "png")
 	if err := s.objects.Put(ctx, key, raw, defaultAvatarMIME); err != nil {
 		return ""
 	}
diff --git a/internal/module/user/logic/login_test.go b/internal/module/user/logic/login_test.go
index 49bedd1..c74428b 100644
--- a/internal/module/user/logic/login_test.go
+++ b/internal/module/user/logic/login_test.go
@@ -27,10 +27,15 @@ func TestAuthenticateTestEmailAnyCode(t *testing.T) {
 	if u1.ID <= 0 || !entity.ValidSparkID(u1.SparkID) || u1.Nickname != "test01" || !entity.ValidQRCode(u1.QRCode) {
 		t.Fatalf("%+v", u1)
 	}
-	prefix := "perm/avatar/" + strconv.FormatInt(u1.ID, 10) + "/"
-	if !strings.HasPrefix(u1.Avatar, prefix) || !strings.HasSuffix(u1.Avatar, ".png") {
+	if !strings.HasPrefix(u1.Avatar, "perm/avatar/") || !strings.HasSuffix(u1.Avatar, ".png") {
 		t.Fatalf("default avatar %s", u1.Avatar)
 	}
+	uid := strconv.FormatInt(u1.ID, 10)
+	for _, part := range strings.Split(u1.Avatar, "/") {
+		if part == uid {
+			t.Fatalf("avatar leaked uid %s", u1.Avatar)
+		}
+	}
 	store, ok := svc.objects.(*memObjects)
 	if !ok {
 		t.Fatal("mem objects")
diff --git a/internal/pkg/i18n/catalog_validate_upload.go b/internal/pkg/i18n/catalog_validate_upload.go
index b6e6ccd..2056036 100644
--- a/internal/pkg/i18n/catalog_validate_upload.go
+++ b/internal/pkg/i18n/catalog_validate_upload.go
@@ -11,6 +11,9 @@ func init() {
 		KeyFieldSize: {
 			ZhCN: "文件大小", En: "File size", ZhTW: "檔案大小",
 		},
+		KeyFieldUploadItems: {
+			ZhCN: "上传列表", En: "Upload list", ZhTW: "上傳列表",
+		},
 		KeyFieldObjectKey: {
 			ZhCN: "对象键", En: "Object key", ZhTW: "物件鍵",
 		},
@@ -50,6 +53,12 @@ func init() {
 		KeyUploadGroupRequired: {
 			ZhCN: "请选择群", En: "Please choose a group", ZhTW: "請選擇群",
 		},
+		KeyUploadItemsRequired: {
+			ZhCN: "请填写要上传的文件", En: "Please provide files to upload", ZhTW: "請填寫要上傳的檔案",
+		},
+		KeyUploadItemsInvalid: {
+			ZhCN: "一次最多签发 3 个上传凭证", En: "At most 3 upload credentials per request", ZhTW: "一次最多簽發 3 個上傳憑證",
+		},
 		KeyFavoriteMsgRequired: {
 			ZhCN: "请选择消息", En: "Please choose a message", ZhTW: "請選擇訊息",
 		},
diff --git a/internal/pkg/i18n/keys.go b/internal/pkg/i18n/keys.go
index adbcff0..2d7e935 100644
--- a/internal/pkg/i18n/keys.go
+++ b/internal/pkg/i18n/keys.go
@@ -42,6 +42,7 @@ const (
 	KeyFieldPurpose        = "field.purpose"
 	KeyFieldMime           = "field.mime"
 	KeyFieldSize           = "field.size"
+	KeyFieldUploadItems    = "field.upload_items"
 	KeyFieldObjectKey      = "field.object_key"
 	KeyFieldMsgID          = "field.msg_id"
 	KeyFieldClientMsgID    = "field.client_msg_id"
@@ -90,6 +91,8 @@ const (
 	KeyUploadKeyRequired        = "validate.upload.key_required"
 	KeyUploadKeyInvalid         = "validate.upload.key_invalid"
 	KeyUploadGroupRequired      = "validate.upload.group_required"
+	KeyUploadItemsRequired      = "validate.upload.items_required"
+	KeyUploadItemsInvalid       = "validate.upload.items_invalid"
 	KeyFavoriteMsgRequired      = "validate.favorite.msg_required"
 	KeyFavoriteMsgInvalid       = "validate.favorite.msg_invalid"
 	KeyMessageClientMsgRequired = "validate.message.client_msg_required"
diff --git a/internal/pkg/reqctx/reqctx.go b/internal/pkg/reqctx/reqctx.go
index ab6223b..1a72c39 100644
--- a/internal/pkg/reqctx/reqctx.go
+++ b/internal/pkg/reqctx/reqctx.go
@@ -3,7 +3,8 @@ package reqctx
 import (
 	"context"
 	"crypto/rand"
-	"encoding/hex"
+	"encoding/binary"
+	"math/big"
 	"net"
 	"strings"
 	"time"
@@ -91,11 +92,51 @@ func stripHost(v string) string {
 	return v
 }
 
-// NewID returns a 16-byte hex id for request_id.
+const (
+	base62Alphabet = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
+	base62Len      = 11
+	objectNameLen  = 16
+	objectNameSrc  = 12
+)
+
+// NewID returns an 8-byte base62 id (11 chars) for request_id and JWT jti.
 func NewID() string {
-	var b [16]byte
+	var b [8]byte
 	if _, err := rand.Read(b[:]); err != nil {
-		return "00000000000000000000000000000000"
+		return "00000000000"
 	}
-	return hex.EncodeToString(b[:])
+	return encodeBase62(binary.BigEndian.Uint64(b[:]))
+}
+
+// NewObjectName returns a 12-byte base62 id (16 chars) for object_key filenames. Not Snowflake.
+func NewObjectName() string {
+	return randomBase62(objectNameSrc, objectNameLen)
+}
+
+func encodeBase62(n uint64) string {
+	var out [base62Len]byte
+	for i := base62Len - 1; i >= 0; i-- {
+		out[i] = base62Alphabet[n%62]
+		n /= 62
+	}
+	return string(out[:])
+}
+
+func randomBase62(byteN, width int) string {
+	if byteN < 1 || width < 1 {
+		return ""
+	}
+	b := make([]byte, byteN)
+	if _, err := rand.Read(b); err != nil {
+		return strings.Repeat("0", width)
+	}
+	n := new(big.Int).SetBytes(b)
+	out := make([]byte, width)
+	base := big.NewInt(62)
+	r := new(big.Int)
+	for i := width - 1; i >= 0; i-- {
+		n.DivMod(n, base, r)
+		out[i] = base62Alphabet[r.Int64()]
+	}
+	return string(out)
 }
diff --git a/internal/pkg/reqctx/reqctx_test.go b/internal/pkg/reqctx/reqctx_test.go
index ddd497e..b39e07c 100644
--- a/internal/pkg/reqctx/reqctx_test.go
+++ b/internal/pkg/reqctx/reqctx_test.go
@@ -1,6 +1,9 @@
 package reqctx
 
-import "testing"
+import (
+	"strings"
+	"testing"
+)
 
 func TestParseHTTPRealIP(t *testing.T) {
 	got := ParseHTTPRealIP(" 203.0.113.10 ", "198.51.100.1, 192.0.2.1", "192.0.2.1:1234")
@@ -27,6 +30,48 @@ func TestRealIPFromContext(t *testing.T) {
 	}
 }
 
+func TestNewIDLength(t *testing.T) {
+	id := NewID()
+	if len(id) != 11 {
+		t.Fatalf("len %d %q", len(id), id)
+	}
+	for i := 0; i < len(id); i++ {
+		if !strings.ContainsRune(base62Alphabet, rune(id[i])) {
+			t.Fatalf("char %q in %q", id[i], id)
+		}
+	}
+	if id == NewID() {
+		t.Fatal("not unique")
+	}
+}
+
+func TestNewObjectNameLength(t *testing.T) {
+	id := NewObjectName()
+	if len(id) != 16 {
+		t.Fatalf("len %d %q", len(id), id)
+	}
+	for i := 0; i < len(id); i++ {
+		if !strings.ContainsRune(base62Alphabet, rune(id[i])) {
+			t.Fatalf("char %q in %q", id[i], id)
+		}
+	}
+	if id == NewObjectName() {
+		t.Fatal("not unique")
+	}
+}
+
+func TestEncodeBase62(t *testing.T) {
+	if got := encodeBase62(0); got != "00000000000" {
+		t.Fatalf("%q", got)
+	}
+	if got := encodeBase62(61); got != "0000000000z" {
+		t.Fatalf("%q", got)
+	}
+	if got := encodeBase62(62); got != "00000000010" {
+		t.Fatalf("%q", got)
+	}
+}
+
 func TestRequestIDFromContext(t *testing.T) {
 	ctx := With(t.Context(), &RequestContext{RequestID: "abc"})
 	if RequestID(ctx) != "abc" {
diff --git a/internal/transport/http/docs/openapi.yaml b/internal/transport/http/docs/openapi.yaml
index f4c5853..e54cd4d 100644
--- a/internal/transport/http/docs/openapi.yaml
+++ b/internal/transport/http/docs/openapi.yaml
@@ -7,7 +7,7 @@ info:
 
     ## 环境与地址
 
-    公网只开放 `443`。Nginx 按 TLS SNI 分流：HTTP 证书打到 `sparkapi.wyrs365.com`，IM 证书打到 `sparkim.wyrs365.com`。进程本身只绑本机。
+    公网只开放 `443`。Nginx 按 TLS SNI 分流：HTTP 证书打到 `sparkapi.wyrs365.com`，IM 证书打到 `sparkim.wyrs365.com`，对象存储（RustFS S3）打到 `sparkr.wyrs365.com`。进程本身只绑本机。
 
     | 环境 | 用途 | HTTP Base URL | IM 长连接 |
     | --- | --- | --- | --- |
@@ -36,7 +36,7 @@ info:
     | --- | --- | --- |
     | `code` | **字符串** | `"0"` 成功；其它失败。不要用数字 `0` 比较。全表见 [错误码](/docs/errors)。 |
     | `msg` | 字符串 | 给人看的文案，随请求语言变化（`zh-CN` / `en` / `zh-TW`）。成功一般为 `ok`。 |
-    | `request_id` | 字符串 | 服务端生成的本次请求 id。客户端不用传；从响应体读取。与 Header `X-Request-ID` 相同。 |
+    | `request_id` | 字符串 | 服务端生成，11 位 base62（`0-9A-Za-z`）。客户端不用传；从响应体读取。与 Header `X-Request-ID` 相同。 |
     | `data` | object / array | 成功时为业务对象；失败时固定 `{}`。字段缺失当空对象，不要当 `null`。 |
 
     **判定成功只看 `code === "0"`。** 不要只看 HTTP 状态码。
@@ -655,7 +655,7 @@ paths:
                   uid: 1940000000000000000
                   spark_id: alice_ok
                   nickname: test01
-                  avatar: perm/avatar/1940000000000000000/20260917/1940000000000000001.png
+                  avatar: perm/avatar/20260917/3H8kPq2mN1Rabcde.png
                   qrcode: "-NDveu-9Q"
                   birthday: ""
                   gender: 0
@@ -1106,9 +1106,13 @@ paths:
       description: |
         客户端只传 `purpose` / `mime` / `size`，服务端生成 object_key 并签发短时 Presigned PUT。
         文件直传 RustFS，不经过 Gin。
-        `avatar` 写入 `perm/avatar/{uid}/…`（不过期）；`group_avatar` 写入 `perm/group/{群号}/…`（需 `group_id`，群主/管理员）；
-        聊天媒体写入 `chat/{yyyyMMdd}/{uid}/…`（桶生命周期过期）。
-        客户端 PUT 时必须带返回的 `headers`（至少 `Content-Type`）。消息与头像只存 `object_key`。
+        `avatar` 写入 `perm/avatar/{yyyyMMdd}/{name}.{ext}`（不过期，路径不含 uid）；
+        `group_avatar` 写入 `perm/group/{群号}/{name}.{ext}`（需 `group_id`，群主/管理员）；
+        聊天按类型：`chat/image|voice|video|gif|file/{yyyyMMdd}/{name}.{ext}`（桶生命周期按前缀过期）。
+        `{name}` 为服务端 16 位 base62 随机串，不占用 Snowflake。
+        发图片：客户端压成 JPEG/PNG 后 `POST /v1/files/batch` 直传缩略图、压缩大图、原图（未勾选原图只传前两项）。
+        服务端不转码。iOS HEIC、Android WebP 须客户端先转 JPEG/PNG，两端才能互看。
+        客户端 PUT 必须原样带返回的 `headers`。消息只存 object_key。
       operationId: createUploadCredential
       requestBody:
         required: true
@@ -1131,12 +1135,61 @@ paths:
                 code: "0"
                 msg: ok
                 data:
-                  object_key: chat/20260917/1/2.jpg
-                  upload_url: http://47.236.66.9:9000/spark/chat/20260917/1/2.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256
+                  object_key: chat/image/20260917/3H8kPq2mN1Rabcde.jpg
+                  upload_url: https://sparkr.wyrs365.com/spark/chat/image/20260917/3H8kPq2mN1Rabcde.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256
                   method: PUT
                   headers:
                     Content-Type: image/jpeg
+                    Content-Length: "245760"
+                    If-None-Match: "*"
                   expires_in: 900
+  /v1/files/batch:
+    post:
+      tags: [files]
+      summary: 批量签发直传凭证
+      description: |
+        一次返回 1～3 个 Presigned PUT，顺序与 `items` 相同。聊天图片请按「缩略图、压缩大图、原图」排列；未勾选原图只传前两项。
+        mime 仅 `image/jpeg` / `image/png`（HEIC、WebP 请客户端先转）。限流按条数计入 `upload_per_second`。文件仍直传 RustFS。
+      operationId: createUploadCredentials
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              $ref: "#/components/schemas/CreateUploadBatchRequest"
+            example:
+              items:
+                - purpose: chat_image
+                  mime: image/jpeg
+                  size: 8192
+                - purpose: chat_image
+                  mime: image/jpeg
+                  size: 245760
+                - purpose: chat_image
+                  mime: image/jpeg
+                  size: 3500000
+      responses:
+        "200":
+          description: 统一 envelope
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/Envelope"
+              example:
+                code: "0"
+                msg: ok
+                data:
+                  items:
+                    - object_key: chat/image/20260917/3H8kPq2mN1Rabcde.jpg
+                      method: PUT
+                      headers:
+                        Content-Type: image/jpeg
+                        Content-Length: "8192"
+                        If-None-Match: "*"
+                    - object_key: chat/image/20260917/4kPq2mN1RabcdeXY.jpg
+                      method: PUT
+                    - object_key: chat/image/20260917/5mN1RabcdeXY12ab.jpg
+                      method: PUT
   /v1/files/downloads:
     post:
       tags: [files]
@@ -1181,7 +1234,7 @@ paths:
       tags: [favorites]
       summary: 收藏一条消息
       description: |
-        会话成员可将消息收入收藏。图片/语音/视频/文件会 CopyObject 到 `perm/fav/{uid}/…`。
+        会话成员可将消息收入收藏。图片/语音/视频/文件会 CopyObject 到 `perm/fav/{yyyyMMdd}/{name}.{ext}`。
         源对象已从 `chat/` 过期删除则失败（`code=40402`），不提供本地补传。
         同一 `msg_id` 重复收藏返回已有记录。撤回不影响已收藏快照。
       operationId: createFavorite
@@ -1477,8 +1530,8 @@ components:
           example: ok
         request_id:
           type: string
-          description: 服务端生成的本次请求 id。客户端不用传，从响应体读取。
-          example: a1b2c3d4e5f6a7b8a1b2c3d4e5f6a7b8
+          description: 服务端生成的本次请求 id（11 位 base62，`0-9A-Za-z`）。客户端不用传，从响应体读取。
+          example: 3H8kPq2mN1R
         data:
           type: object
           additionalProperties: true
@@ -1743,6 +1796,9 @@ components:
         mime:
           type: string
           example: image/jpeg
+          description: |
+            avatar / group_avatar / chat_image 仅 image/jpeg、image/jpg、image/png。
+            iOS HEIC、Android WebP 须客户端转成 JPEG/PNG 再申请凭证。
         size:
           type: integer
           format: int64
@@ -1752,6 +1808,16 @@ components:
           format: int64
           minimum: 1
           description: purpose=group_avatar 时必填，为自增群号
+    CreateUploadBatchRequest:
+      type: object
+      required: [items]
+      properties:
+        items:
+          type: array
+          minItems: 1
+          maxItems: 3
+          items:
+            $ref: "#/components/schemas/CreateUploadRequest"
     CreateDownloadRequest:
       type: object
       required: [object_key]
@@ -1792,6 +1858,39 @@ components:
               properties:
                 body:
                   type: string
+            image:
+              type: object
+              description: |
+                t=2。点开看 `key`（压缩预览）；气泡用 `thumb_key`；`orig_key` 有则显示「查看原图」。
+                三档由客户端压成 JPEG/PNG 后 `POST /v1/files/batch` 直传。服务端不转码；不要传 HEIC/WebP。
+              required: [key]
+              properties:
+                key:
+                  type: string
+                  description: 点开查看用的压缩图 object_key
+                thumb_key:
+                  type: string
+                  description: 气泡缩略图，可省略
+                orig_key:
+                  type: string
+                  description: 原图 object_key；空则没有「查看原图」
+                orig_size:
+                  type: integer
+                  format: int64
+                  description: 原图像素文件大小，供「查看原图 3.2MB」按钮
+                orig_w:
+                  type: integer
+                orig_h:
+                  type: integer
+                mime:
+                  type: string
+                w:
+                  type: integer
+                h:
+                  type: integer
+                size:
+                  type: integer
+                  format: int64
             at_all:
               type: boolean
               description: "@所有人，仅群主/管理员"
diff --git a/internal/transport/http/file_test.go b/internal/transport/http/file_test.go
index ff79f88..f2491f0 100644
--- a/internal/transport/http/file_test.go
+++ b/internal/transport/http/file_test.go
@@ -27,11 +27,11 @@ import (
 
 type stubPresign struct{}
 
-func (stubPresign) PresignPut(_ context.Context, key, _ string, _ time.Duration) (string, error) {
+func (s *stubPresign) PresignPut(_ context.Context, key, _ string, _ int64, _ time.Duration) (string, error) {
 	return "http://rustfs.test/" + key + "?sig=1", nil
 }
 
-func (stubPresign) PresignGet(_ context.Context, key string, _ time.Duration) (string, error) {
+func (s *stubPresign) PresignGet(_ context.Context, key string, _ time.Duration) (string, error) {
 	return "http://rustfs.test/" + key + "?get=1", nil
 }
 
@@ -48,7 +48,7 @@ func testFileEngine(t *testing.T) (*ginEngineBundle, *id.Generator, *msgmodel.Me
 	users := userlogic.NewService(usermodel.NewMemoryRepo(), usermodel.NewMemoryCodes(), ids, nil)
 	msgs := msgmodel.NewMemoryRepo()
 	convs := convmodel.NewMemoryP2P()
-	files := uploadlogic.NewService(stubPresign{}, ids, uploadlogic.Options{
+	files := uploadlogic.NewService(&stubPresign{}, uploadlogic.Options{
 		Now: func() time.Time { return time.Date(2026, 9, 17, 0, 0, 0, 0, time.UTC) },
 	})
 	favs := favlogic.NewService(favmodel.NewMemoryRepo(), msgs, convs, nil, ids)
@@ -71,13 +71,25 @@ func TestUploadCredentialHTTP(t *testing.T) {
 		ObjectKey string `json:"object_key"`
 		Method    string `json:"method"`
 	}
-	if err := json.Unmarshal(env.Data, &cred); err != nil || cred.Method != "PUT" || !strings.Contains(cred.ObjectKey, "chat/20260917/") {
+	if err := json.Unmarshal(env.Data, &cred); err != nil || cred.Method != "PUT" || !strings.Contains(cred.ObjectKey, "chat/image/20260917/") {
 		t.Fatalf("%s %v", env.Data, err)
 	}
 	bad := authJSON(t, h, &tok, http.MethodPost, "/v1/files", `{"purpose":"avatar","mime":"application/pdf","size":10}`)
 	if bad.Code != errs.ErrInvalidArgument.Code {
 		t.Fatalf("mime %+v", bad)
 	}
+	batch := authJSON(t, h, &tok, http.MethodPost, "/v1/files/batch", `{"items":[{"purpose":"chat_image","mime":"image/jpeg","size":1024},{"purpose":"chat_image","mime":"image/jpeg","size":2048}]}`)
+	if batch.Code != "0" {
+		t.Fatalf("batch %+v", batch)
+	}
+	var set struct {
+		Items []struct {
+			ObjectKey string `json:"object_key"`
+		} `json:"items"`
+	}
+	if err := json.Unmarshal(batch.Data, &set); err != nil || len(set.Items) != 2 || set.Items[0].ObjectKey == set.Items[1].ObjectKey {
+		t.Fatalf("%s %v", batch.Data, err)
+	}
 }
 
 func TestFavoriteTextHTTP(t *testing.T) {
diff --git a/internal/transport/http/handler/file/handler.go b/internal/transport/http/handler/file/handler.go
index 25dbaa0..59c1bda 100644
--- a/internal/transport/http/handler/file/handler.go
+++ b/internal/transport/http/handler/file/handler.go
@@ -36,6 +36,24 @@ func (h *Handler) Create(c *gin.Context) {
 	respond.JSON(c, out)
 }
 
+func (h *Handler) CreateBatch(c *gin.Context) {
+	uid, ok := currentUID(c)
+	if !ok {
+		return
+	}
+	var in uploadlogic.BatchCreateInput
+	if err := respond.BindJSON(c, &in); err != nil {
+		respond.JSONError(c, err)
+		return
+	}
+	out, err := h.files.CreateCredentials(c.Request.Context(), uid, &in)
+	if err != nil {
+		respond.JSONError(c, err)
+		return
+	}
+	respond.JSON(c, out)
+}
+
 func (h *Handler) Download(c *gin.Context) {
 	uid, ok := currentUID(c)
 	if !ok {
diff --git a/internal/transport/http/router.go b/internal/transport/http/router.go
index fc6362b..c96d3b7 100644
--- a/internal/transport/http/router.go
+++ b/internal/transport/http/router.go
@@ -132,6 +132,7 @@ func registerFileRoutes(v1 *gin.RouterGroup, deps *EngineDeps) {
 	h := filehandler.New(deps.Files)
 	g := v1.Group("/files")
 	g.POST("", h.Create)
+	g.POST("/batch", h.CreateBatch)
 	g.POST("/downloads", h.Download)
 }
 
diff --git a/internal/transport/http/server_test.go b/internal/transport/http/server_test.go
index a63cfbc..4e36458 100644
--- a/internal/transport/http/server_test.go
+++ b/internal/transport/http/server_test.go
@@ -34,7 +34,7 @@ func TestHealthzEnvelopeAndTraceHeaders(t *testing.T) {
 		t.Fatalf("status %d", w.Code)
 	}
 	got := w.Header().Get("X-Request-ID")
-	if len(got) != 32 {
+	if len(got) != 11 {
 		t.Fatalf("server request id %q headers %v", got, w.Header())
 	}
 	if w.Header().Get("X-Trace-ID") != "" {
@@ -47,7 +47,7 @@ func TestHealthzEnvelopeAndTraceHeaders(t *testing.T) {
 	if env.Code != "0" || env.Msg != "ok" {
 		t.Fatalf("%+v", env)
 	}
-	if env.RequestID != got || len(env.RequestID) != 32 {
+	if env.RequestID != got || len(env.RequestID) != 11 {
 		t.Fatalf("body request_id %q header %q", env.RequestID, got)
 	}
 	if !bytes.Contains(env.Data, []byte(`"status":"ok"`)) {
@@ -82,7 +82,7 @@ func TestReadyzHTTPStatus(t *testing.T) {
 	if env.Code != errs.ErrAvailable.Code || !bytes.Contains(env.Data, []byte(`"mysql":"down"`)) {
 		t.Fatalf("%+v", env)
 	}
-	if len(env.RequestID) != 32 {
+	if len(env.RequestID) != 11 {
 		t.Fatalf("readyz request_id %q", env.RequestID)
 	}
 }