Api DesignSAFE

everything-claude-code 中文翻译项目:完整的 Claude Code 配置集合(agents, skills, hooks, commands, rules, MCPs)。源自 Anthropic 黑客松获胜者的实战配置,助力中文工程师高效理解与使用 Claude Code。

The instruction file, verbatim from the audited commit — this is the text the model reads, and the surface the audit's instruction layer examines. Quoted here so you can judge it without cloning anything.

---
name: api-design
description: REST API设计模式,包括资源命名、状态码、分页、过滤、错误响应、版本控制和生产API的速率限制。
origin: ECC
---

# API 设计模式

用于设计一致、对开发者友好的 REST API 的约定和最佳实践。

## 何时启用

* 设计新的 API 端点时
* 审查现有的 API 契约时
* 添加分页、过滤或排序功能时
* 为 API 实现错误处理时
* 规划 API 版本策略时
* 构建面向公众或合作伙伴的 API 时

## 资源设计

### URL 结构

```
# Resources are nouns, plural, lowercase, kebab-case
GET    /api/v1/users
GET    /api/v1/users/:id
POST   /api/v1/users
PUT    /api/v1/users/:id
PATCH  /api/v1/users/:id
DELETE /api/v1/users/:id

# Sub-resources for relationships
GET    /api/v1/users/:id/orders
POST   /api/v1/users/:id/orders

# Actions that don't map to CRUD (use verbs sparingly)
POST   /api/v1/orders/:id/cancel
POST   /api/v1/auth/login
POST   /api/v1/auth/refresh
```

### 命名规则

```
# GOOD
/api/v1/team-members          # kebab-case for multi-word resources
/api/v1/orders?status=active  # query params for filtering
/api/v1/users/123/orders      # nested resources for ownership

# BAD
/api/v1/getUsers              # verb in URL
/api/v1/user                  # singular (use plural)
/api/v1/team_members          # snake_case in URLs
/api/v1/users/123/getOrders   # verb in nested resource
```

## HTTP 方法和状态码

### 方法语义

| 方法 | 幂等性 | 安全性 | 用途 |
|--------|-----------|------|---------|
| GET | 是 | 是 | 检索资源 |
| POST | 否 | 否 | 创建资源,触发操作 |
| PUT | 是 | 否 | 完全替换资源 |
| PATCH | 否\* | 否 | 部分更新资源 |
| DELETE | 是 | 否 | 删除资源 |

\*通过适当的实现,PATCH 可以实现幂等

### 状态码参考

```
# Success
200 OK                    — GET, PUT, PATCH (with response body)
201 Created               — POST (include Location header)
204 No Content            — DELETE, PUT (no response body)

# Client Errors
400 Bad Request           — Validation failure, malformed JSON
401 Unauthorized          — Missing or invalid authentication
403 Forbidden             — Authenticated but not authorized
404 Not Found             — Resource doesn't exist
409 Conflict              — Duplicate entry, state conflict
422 Unprocessable Entity  — Semantically invalid (valid JSON, bad data)
429 Too Many Requests     — Rate limit exceeded

# Server Errors
500 Internal Server Error — Unexpected failure (never expose details)
502 Bad Gateway           — Upstream service failed
503 Service Unavailable   — Temporary overload, include Retry-After
```

### 常见错误

```
# BAD: 200 for everything
{ "status": 200, "success": false, "error": "Not found" }

# GOOD: Use HTTP status codes semantically
HTTP/1.1 404 Not Found
{ "error": { "code": "not_found", "message": "User not found" } }

# BAD: 500 for validation errors
# GOOD: 400 or 422 with field-level details

# BAD: 200 for created resources
# GOOD: 201 with Location header
HTTP/1.1 201 Created
Location: /api/v1/users/abc-123
```

## 响应格式

### 成功响应

```json
{
  "data": {
    "id": "abc-123",
    "email": "[email protected]",
    "name": "Alice",
    "created_at": "2025-01-15T10:30:00Z"
  }
}
```

### 集合响应(带分页)

```json
{
  "data": [
    { "id": "abc-123", "name": "Alice" },
    { "id": "def-456", "name": "Bob" }
  ],
  "meta": {
    "total": 142,
    "page": 1,
    "per_page": 20,
    "total_pages": 8
  },
  "links": {
    "self": "/api/v1/users?page=1&per_page=20",
    "next": "/api/v1/users?page=2&per_page=20",
    "last": "/api/v1/users?page=8&per_page=20"
  }
}
```

### 错误响应

```json
{
  "error": {
    "code": "validation_error",
    "message": "Request validation failed",
    "details": [
      {
        "field": "email",
        "message": "Must be a valid email address",
        "code": "invalid_format"
      },
      {
        "field": "age",
        "message": "Must be between 0 and 150",
        "code": "out_of_range"
      }
    ]
  }
}
```

### 响应包装器变体

```typescript
// Option A: Envelope with data wrapper (recommended for public APIs)
interface ApiResponse<T> {
  data: T;
  meta?: PaginationMeta;
  links?: PaginationLinks;
}

interface ApiError {
  error: {
    code: string;
    message: string;
    details?: FieldError[];
  };
}

// Option B: Flat response (simpler, common for internal APIs)
// Success: just return the resource directly
// Error: return error object
// Distinguish by HTTP status code
```

## 分页

### 基于偏移量(简单)

```
GET /api/v1/users?page=2&per_page=20

# Implementation
SELECT * FROM users
ORDER BY created_at DESC
LIMIT 20 OFFSET 20;
```

**优点:** 易于实现,支持“跳转到第 N 页”
**缺点:** 在大偏移量时速度慢(例如 OFFSET 100000),并发插入时结果不一致

### 基于游标(可扩展)

```
GET /api/v1/users?cursor=eyJpZCI6MTIzfQ&limit=20

# Implementation
SELECT * FROM users
WHERE id > :cursor_id
ORDER BY id ASC
LIMIT 21;  -- fetch one extra to determine has_next
```

```json
{
  "data": [...],
  "meta": {
    "has_next": true,
    "next_cursor": "eyJpZCI6MTQzfQ"
  }
}
```

**优点:** 无论位置如何,性能一致;在并发插入时结果稳定
**缺点:** 无法跳转到任意页面;游标是不透明的

### 何时使用哪种

| 用例 | 分页类型 |
|----------|----------------|
| 管理仪表板,小数据集 (<10K) | 偏移量 |
| 无限滚动,信息流,大数据集 | 游标 |
| 公共 API | 游标(默认)配合偏移量(可选) |
| 搜索结果 | 偏移量(用户期望有页码) |

## 过滤、排序和搜索

### 过滤

```
# Simple equality
GET /api/v1/orders?status=active&customer_id=abc-123

# Comparison operators (use bracket notation)
GET /api/v1/products?price[gte]=10&price[lte]=100
GET /api/v1/orders?created_at[after]=2025-01-01

# Multiple values (comma-separated)
GET /api/v1/products?category=electronics,clothing

# Nested fields (dot notation)
GET /api/v1/orders?customer.country=US
```

### 排序

```
# Single field (prefix - for descending)
GET /api/v1/products?sort=-created_at

# Multiple fields (comma-separated)
GET /api/v1/products?sort=-featured,price,-created_at
```

### 全文搜索

```
# Search query parameter
GET /api/v1/products?q=wireless+headphones

# Field-specific search
GET /api/v1/users?email=alice
```

### 稀疏字段集

```
# Return only specified fields (reduces payload)
GET /api/v1/users?fields=id,name,email
GET /api/v1/orders?fields=id,total,status&include=customer.name
```

## 认证和授权

### 基于令牌的认证

```
# Bearer token in Authorization header
GET /api/v1/users
Authorization: Bearer eyJhbGciOiJIUzI1NiIs...

# API key (for server-to-server)
GET /api/v1/data
X-API-Key: sk_live_abc123
```

### 授权模式

```typescript

SAFEgrade B · trust 89/100 Nothing in the source contradicts what it says it does. Grade A is reserved for packages that have also passed the behavioural sandbox.

What the source does

Filesystem

none-observed

Network

none-observed

Shell

none-observed

Dependencies

pinned

Secrets in source

none-found

Findings (0)

No findings outside the package's declared scope.

Gates applied: no_behavioural_pass.