# 排行榜系统后端API数据格式规范

## 概述

本文档定义了排行榜系统的后端API接口规范，包括请求参数、响应格式和数据模型。

---

## 1. 获取排行榜数据

### 接口信息

- **接口路径**: `/api/ranking/list`
- **请求方法**: `GET`
- **接口描述**: 获取指定类型和时间段的排行榜数据

### 请求参数

| 参数名 | 类型 | 必填 | 说明 | 示例值 |
|--------|------|------|------|--------|
| rankingType | string | 是 | 榜单类型 | `popularity` / `custom` / `activity` |
| timePeriod | string | 是 | 时间段 | `online` / `monthly` / `history` |
| page | number | 否 | 页码（默认1） | `1` |
| pageSize | number | 否 | 每页数量（默认20） | `20` |

### 榜单类型枚举

```json
{
  "popularity": "热度榜",
  "custom": "自制榜",
  "activity": "活动榜"
}
```

### 时间段枚举

```json
{
  "online": "在线",
  "monthly": "本月",
  "history": "历史"
}
```

### 响应格式

```json
{
  "code": 200,
  "message": "success",
  "data": {
    "rankingType": "popularity",
    "timePeriod": "online",
    "hasArtwork": true,
    "total": 100,
    "page": 1,
    "pageSize": 20,
    "list": [
      {
        "rank": 1,
        "userId": "user001",
        "avatar": "https://example.com/avatar/1.jpeg",
        "nickname": "星光璀璨",
        "popularityScore": 73654,
        "artworkImage": "https://example.com/artwork/001.png",
        "artworkId": "artwork001"
      }
    ]
  }
}
```

---

## 2. 获取当前用户排名信息

### 接口信息

- **接口路径**: `/api/ranking/current-user`
- **请求方法**: `GET`
- **接口描述**: 获取当前登录用户在指定榜单中的排名信息

### 请求参数

| 参数名 | 类型 | 必填 | 说明 | 示例值 |
|--------|------|------|------|--------|
| rankingType | string | 是 | 榜单类型 | `popularity` |
| timePeriod | string | 是 | 时间段 | `online` |

### 响应格式

**已上榜状态**:

```json
{
  "code": 200,
  "message": "success",
  "data": {
    "userId": "currentUser",
    "avatar": "https://example.com/avatar/7.jpeg",
    "nickname": "我",
    "popularityScore": 45000,
    "rank": 5,
    "artworkImage": "https://example.com/artwork/current.png",
    "artworkId": "currentUserArtwork",
    "isRanked": true
  }
}
```

**未上榜状态**:

```json
{
  "code": 200,
  "message": "success",
  "data": {
    "userId": "currentUser",
    "avatar": "https://example.com/avatar/7.jpeg",
    "nickname": "我",
    "popularityScore": 371,
    "rank": null,
    "artworkImage": "https://example.com/artwork/current.png",
    "artworkId": "currentUserArtwork",
    "isRanked": false
  }
}
```

---

## 3. 数据模型定义

### RankingUser (排行榜用户对象)

| 字段名 | 类型 | 必填 | 说明 | 备注 |
|--------|------|------|------|------|
| rank | number | 是 | 排名 | 从1开始 |
| userId | string | 是 | 用户ID | 唯一标识 |
| avatar | string | 是 | 头像URL | 完整URL地址 |
| nickname | string | 是 | 用户昵称 | 最大长度20字符 |
| popularityScore | number | 是 | 人气值/积分 | 非负整数 |
| artworkImage | string | 否 | 作品图片URL | 热度榜和自制榜必填 |
| artworkId | string | 否 | 作品ID | 热度榜和自制榜必填 |

**TypeScript 类型定义**:

```typescript
interface RankingUser {
  rank: number;
  userId: string;
  avatar: string;
  nickname: string;
  popularityScore: number;
  artworkImage?: string;  // 活动榜不需要
  artworkId?: string;     // 活动榜不需要
}
```

### CurrentUserRanking (当前用户排名对象)

| 字段名 | 类型 | 必填 | 说明 |
|--------|------|------|------|
| userId | string | 是 | 用户ID |
| avatar | string | 是 | 头像URL |
| nickname | string | 是 | 用户昵称 |
| popularityScore | number | 是 | 人气值/积分 |
| rank | number \| null | 是 | 排名（null表示未上榜） |
| artworkImage | string | 否 | 作品图片URL |
| artworkId | string | 否 | 作品ID |
| isRanked | boolean | 是 | 是否已上榜 |

**TypeScript 类型定义**:

```typescript
interface CurrentUserRanking {
  userId: string;
  avatar: string;
  nickname: string;
  popularityScore: number;
  rank: number | null;
  artworkImage?: string;
  artworkId?: string;
  isRanked: boolean;
}
```

---

## 4. 榜单特性配置

### 榜单类型特性

| 榜单类型 | 类型代码 | 是否包含作品 | 说明 |
|---------|---------|------------|------|
| 热度榜 | popularity | ✅ 是 | 包含 artworkImage 和 artworkId |
| 自制榜 | custom | ✅ 是 | 包含 artworkImage 和 artworkId |
| 活动榜 | activity | ❌ 否 | 不包含作品相关字段 |

### 后端返回字段规则

```javascript
// 热度榜和自制榜
{
  "hasArtwork": true,
  "list": [
    {
      "rank": 1,
      "userId": "user001",
      "avatar": "...",
      "nickname": "...",
      "popularityScore": 73654,
      "artworkImage": "...",  // 必须返回
      "artworkId": "..."      // 必须返回
    }
  ]
}

// 活动榜
{
  "hasArtwork": false,
  "list": [
    {
      "rank": 1,
      "userId": "user201",
      "avatar": "...",
      "nickname": "...",
      "popularityScore": 58321
      // 不包含 artworkImage 和 artworkId
    }
  ]
}
```

---

## 5. 错误响应格式

### 通用错误响应

```json
{
  "code": 400,
  "message": "参数错误：rankingType 必须为 popularity、custom 或 activity",
  "data": null
}
```

### 错误码定义

| 错误码 | 说明 | 示例消息 |
|--------|------|---------|
| 400 | 请求参数错误 | "参数错误：rankingType 不能为空" |
| 401 | 未登录或token失效 | "请先登录" |
| 404 | 资源不存在 | "榜单数据不存在" |
| 500 | 服务器内部错误 | "服务器错误，请稍后重试" |

---

## 6. 请求示例

### 示例1: 获取热度榜在线排行

**请求**:
```http
GET /api/ranking/list?rankingType=popularity&timePeriod=online&page=1&pageSize=20
Authorization: Bearer {token}
```

**响应**:
```json
{
  "code": 200,
  "message": "success",
  "data": {
    "rankingType": "popularity",
    "timePeriod": "online",
    "hasArtwork": true,
    "total": 14,
    "page": 1,
    "pageSize": 20,
    "list": [
      {
        "rank": 1,
        "userId": "user001",
        "avatar": "https://cdn.example.com/avatar/1.jpeg",
        "nickname": "星光璀璨",
        "popularityScore": 73654,
        "artworkImage": "https://cdn.example.com/artwork/001.png",
        "artworkId": "artwork001"
      },
      {
        "rank": 2,
        "userId": "user002",
        "avatar": "https://cdn.example.com/avatar/2.jpeg",
        "nickname": "梦想追逐者",
        "popularityScore": 68921,
        "artworkImage": "https://cdn.example.com/artwork/002.jpeg",
        "artworkId": "artwork002"
      }
    ]
  }
}
```

### 示例2: 获取活动榜本月排行

**请求**:
```http
GET /api/ranking/list?rankingType=activity&timePeriod=monthly&page=1&pageSize=20
Authorization: Bearer {token}
```

**响应**:
```json
{
  "code": 200,
  "message": "success",
  "data": {
    "rankingType": "activity",
    "timePeriod": "monthly",
    "hasArtwork": false,
    "total": 3,
    "page": 1,
    "pageSize": 20,
    "list": [
      {
        "rank": 1,
        "userId": "user203",
        "avatar": "https://cdn.example.com/avatar/5.jpeg",
        "nickname": "活跃用户",
        "popularityScore": 87654
      },
      {
        "rank": 2,
        "userId": "user201",
        "avatar": "https://cdn.example.com/avatar/3.jpeg",
        "nickname": "活动之星",
        "popularityScore": 76543
      }
    ]
  }
}
```

### 示例3: 获取当前用户排名

**请求**:
```http
GET /api/ranking/current-user?rankingType=popularity&timePeriod=online
Authorization: Bearer {token}
```

**响应（已上榜）**:
```json
{
  "code": 200,
  "message": "success",
  "data": {
    "userId": "currentUser",
    "avatar": "https://cdn.example.com/avatar/7.jpeg",
    "nickname": "我",
    "popularityScore": 45000,
    "rank": 5,
    "artworkImage": "https://cdn.example.com/artwork/current.png",
    "artworkId": "currentUserArtwork",
    "isRanked": true
  }
}
```

**响应（未上榜）**:
```json
{
  "code": 200,
  "message": "success",
  "data": {
    "userId": "currentUser",
    "avatar": "https://cdn.example.com/avatar/7.jpeg",
    "nickname": "我",
    "popularityScore": 371,
    "rank": null,
    "artworkImage": "https://cdn.example.com/artwork/current.png",
    "artworkId": "currentUserArtwork",
    "isRanked": false
  }
}
```

---

## 7. 数据验证规则

### 后端验证要求

1. **rankingType 验证**
   - 必填
   - 只能是: `popularity`, `custom`, `activity`

2. **timePeriod 验证**
   - 必填
   - 只能是: `online`, `monthly`, `history`

3. **page 验证**
   - 可选，默认为 1
   - 必须是正整数
   - 最小值: 1

4. **pageSize 验证**
   - 可选，默认为 20
   - 必须是正整数
   - 范围: 1-100

5. **用户数据验证**
   - `userId`: 非空字符串
   - `nickname`: 非空字符串，最大20字符
   - `avatar`: 有效的URL格式
   - `popularityScore`: 非负整数
   - `rank`: 正整数（从1开始）

6. **作品数据验证**（仅热度榜和自制榜）
   - `artworkImage`: 有效的URL格式
   - `artworkId`: 非空字符串

---

## 8. 性能优化建议

### 缓存策略

1. **排行榜数据缓存**
   - 缓存时间: 5分钟
   - 缓存键: `ranking:{rankingType}:{timePeriod}:{page}`

2. **用户排名缓存**
   - 缓存时间: 1分钟
   - 缓存键: `user_rank:{userId}:{rankingType}:{timePeriod}`

### 数据库查询优化

1. 为 `popularityScore` 字段建立索引
2. 为 `userId` 字段建立索引
3. 使用 Redis 存储实时排行榜数据（Sorted Set）

---

## 9. 前后端数据映射

### 前端 Mock 数据 → 后端数据库字段

| 前端字段 | 后端数据库字段 | 类型 | 说明 |
|---------|--------------|------|------|
| rank | - | computed | 根据 popularityScore 计算 |
| userId | user_id | varchar(50) | 用户唯一标识 |
| avatar | avatar_url | varchar(255) | 头像URL |
| nickname | nickname | varchar(50) | 用户昵称 |
| popularityScore | popularity_score | int | 人气值 |
| artworkImage | artwork_image_url | varchar(255) | 作品图片URL |
| artworkId | artwork_id | varchar(50) | 作品ID |

### 数据库表结构建议

```sql
-- 用户排行榜表
CREATE TABLE user_rankings (
    id BIGINT PRIMARY KEY AUTO_INCREMENT,
    user_id VARCHAR(50) NOT NULL,
    ranking_type ENUM('popularity', 'custom', 'activity') NOT NULL,
    time_period ENUM('online', 'monthly', 'history') NOT NULL,
    popularity_score INT NOT NULL DEFAULT 0,
    artwork_id VARCHAR(50),
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    INDEX idx_ranking_score (ranking_type, time_period, popularity_score DESC),
    INDEX idx_user_ranking (user_id, ranking_type, time_period)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- 用户基本信息表
CREATE TABLE users (
    user_id VARCHAR(50) PRIMARY KEY,
    nickname VARCHAR(50) NOT NULL,
    avatar_url VARCHAR(255),
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- 作品信息表
CREATE TABLE artworks (
    artwork_id VARCHAR(50) PRIMARY KEY,
    user_id VARCHAR(50) NOT NULL,
    image_url VARCHAR(255) NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    INDEX idx_user_artwork (user_id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
```

---

## 10. 版本历史

| 版本 | 日期 | 修改内容 | 修改人 |
|------|------|---------|--------|
| 1.0.0 | 2024-03-11 | 初始版本 | - |

---

## 附录: TypeScript 完整类型定义

```typescript
// 榜单类型枚举
export enum RankingType {
  POPULARITY = 'popularity',
  CUSTOM = 'custom',
  ACTIVITY = 'activity'
}

// 时间段枚举
export enum TimePeriod {
  ONLINE = 'online',
  MONTHLY = 'monthly',
  HISTORY = 'history'
}

// 排行榜用户接口
export interface RankingUser {
  rank: number;
  userId: string;
  avatar: string;
  nickname: string;
  popularityScore: number;
  artworkImage?: string;
  artworkId?: string;
}

// 当前用户排名接口
export interface CurrentUserRanking extends RankingUser {
  rank: number | null;
  isRanked: boolean;
}

// 排行榜列表请求参数
export interface RankingListRequest {
  rankingType: RankingType;
  timePeriod: TimePeriod;
  page?: number;
  pageSize?: number;
}

// 排行榜列表响应数据
export interface RankingListResponse {
  rankingType: RankingType;
  timePeriod: TimePeriod;
  hasArtwork: boolean;
  total: number;
  page: number;
  pageSize: number;
  list: RankingUser[];
}

// 当前用户排名请求参数
export interface CurrentUserRankingRequest {
  rankingType: RankingType;
  timePeriod: TimePeriod;
}

// API 响应包装
export interface ApiResponse<T> {
  code: number;
  message: string;
  data: T | null;
}
```