python
 
    ````python
 
```python
```python
    from flask import Flask, request, jsonify
    from flask_sqlalchemy import SQLAlchemy
    from flask_jwt_extended import JWTManager, create_access_token, jwt_required, get_jwt_identity
    from flask_mail import Mail, Message
    from datetime import datetime, timedelta
    import bcrypt
    import secrets
 
    app = Flask(__name__)
    app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///auth.db'
    app.config['JWT_SECRET_KEY'] = 'your-secret-key'
    app.config['JWT_ACCESS_TOKEN_EXPIRES'] = timedelta(hours=24)
    app.config['MAIL_SERVER'] = 'smtp.gmail.com'
    app.config['MAIL_PORT'] = 587
    app.config['MAIL_USE_TLS'] = True
    app.config['MAIL_USERNAME'] = '[email protected]'
    app.config['MAIL_PASSWORD'] = 'your-password'
 
    db = SQLAlchemy(app)
    jwt = JWTManager(app)
    mail = Mail(app)
 
    class User(db.Model):

    class PasswordReset(db.Model):

    def register():

    if not data.get('username') or not data.get('email') or not data.get('password'):
    return jsonify({'error': 'Missing required fields'}), 400
 

    if User.query.filter_by(username=data['username']).first():
    return jsonify({'error': 'Username already exists'}), 400
 

    if User.query.filter_by(email=data['email']).first():
    return jsonify({'error': 'Email already exists'}), 400
 

    if len(data['password']) < 8:
    return jsonify({'error': 'Password must be at least 8 characters'}), 400
 

    bcrypt.gensalt()
    ).decode('utf-8')
    )
 
    db.session.add(user)
    db.session.commit()
 

    return jsonify({
    'message': 'User registered successfully',
    'user': {
    'id': user.id,
    'username': user.username,
    'email': user.email
    },
    'access_token': access_token
    }), 201
 
    @app.route('/login', methods=['POST'])
    def login():

    if not data.get('username') or not data.get('password'):
    return jsonify({'error': 'Missing username or password'}), 400
 

    if not user or not bcrypt.checkpw(
    data['password'].encode('utf-8'),
    user.password_hash.encode('utf-8')
    ):
    return jsonify({'error': 'Invalid username or password'}), 401
 
    if not user.is_active:
    return jsonify({'error': 'Account is deactivated'}), 403
 

    return jsonify({
    'message': 'Login successful',
    'user': {
    'id': user.id,
    'username': user.username,
    'email': user.email
    },
    'access_token': access_token
    })
 
    @app.route('/me', methods=['GET'])
    @jwt_required()
    def get_current_user():

    if not user:
    return jsonify({'error': 'User not found'}), 404
 
    return jsonify({
    'id': user.id,
    'username': user.username,
    'email': user.email,
    'is_active': user.is_active,
    'created_at': user.created_at.isoformat()
    })
 
    @app.route('/request-password-reset', methods=['POST'])
    def request_password_reset():

    if not data.get('email'):
    return jsonify({'error': 'Email is required'}), 400
 
    user = User.query.filter_by(email=data['email']).first()
 
    if not user:

    return jsonify({
    'message': 'If the email exists, a reset link has been sent'
    }), 200
 

    mail.send(msg)
 
    return jsonify({
    'message': 'If the email exists, a reset link has been sent'
    }), 200
 
    @app.route('/reset-password', methods=['POST'])
    def reset_password():

    if not data.get('token') or not data.get('password'):
    return jsonify({'error': 'Token and password are required'}), 400
 

    if not password_reset:
    return jsonify({'error': 'Invalid or expired reset token'}), 400
 
    if password_reset.expires_at < datetime.utcnow():
    return jsonify(&#123;'error': 'Reset token has expired'&#125;), 400
 

    if len(data['password']) < 8:
    return jsonify({'error': 'Password must be at least 8 characters'}), 400
 

    bcrypt.gensalt()
    ).decode('utf-8')
 

    return jsonify({'message': 'Password reset successful'}), 200
 
    @app.route('/change-password', methods=['POST'])
    @jwt_required()
    def change_password():

    if not data.get('current_password') or not data.get('new_password'):
    return jsonify({'error': 'Current password and new password are required'}), 400
 
    user = User.query.get(user_id)
 

    if not bcrypt.checkpw(
    data['current_password'].encode('utf-8'),
    user.password_hash.encode('utf-8')
    ):
    return jsonify({'error': 'Current password is incorrect'}), 400
 

    if len(data['new_password']) < 8:
    return jsonify({'error': 'New password must be at least 8 characters'}), 400
 

    bcrypt.gensalt()
    ).decode('utf-8')
 
    db.session.commit()
 
    return jsonify({'message': 'Password changed successfully'}), 200
 
    if __name__ == '__main__':
    with app.app_context():
    db.create_all()
    app.run(debug=True)
 

 
> - 用户注册功能
> - 用户登录功能
> - JWT 认证
> - 密码重置请求
> - 密码重置
> - 修改密码
> - 邮件发送
> - 数据验证
> - 错误处理
 
### 2. 从 API 规范生成代码
 
# 示例：从 OpenAPI 规范生成代码
用户请求：
"根据这个 OpenAPI 规范生成 API 代码"
OpenAPI 规范：
 
````yaml
 
`yaml
 
openapi: 3.0.0
info:
title: Product API
version: 1.0.0
 
paths:
/products:
get:
summary: Get all products
parameters:
 
 - name: page
 
in: query
schema:
type: integer
 
 - name: per_page
 
in: query
schema:
type: integer
responses:
'200':
description: Success
content:
application/json:
schema:
type: object
properties:
products:
type: array
items:
$ref: '#/components/schemas/Product'
total:
type: integer
page:
type: integer
 
post:
summary: Create a product
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/ProductCreate'
responses:
'201':
description: Created
content:
application/json:
schema:
$ref: '#/components/schemas/Product'
 
/products/{product_id}:
get:
summary: Get a product
parameters:
 
 - name: product_id
 
in: path
required: true
schema:
type: integer
responses:
'200':
description: Success
content:
application/json:
schema:
$ref: '#/components/schemas/Product'
 
put:
summary: Update a product
parameters:
 
 - name: product_id
 
in: path
required: true
schema:
type: integer
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/ProductUpdate'
responses:
'200':
description: Success
content:
application/json:
schema:
$ref: '#/components/schemas/Product'
 
delete:
summary: Delete a product
parameters:
 
 - name: product_id
 
in: path
required: true
schema:
type: integer
responses:
'204':
description: No content
 
components:
schemas:
Product:
type: object
properties:
id:
type: integer
name:
type: string
description:
type: string
price:
type: number
stock:
type: integer
category:
type: string
created_at:
type: string
format: date-time
updated_at:
type: string
format: date-time
 
ProductCreate:
type: object
required:
 
 - name
 - price
 - stock
 - category
 
properties:
name:
type: string
description:
type: string
price:
type: number
stock:
type: integer
category:
type: string
 
ProductUpdate:
type: object
properties:
name:
type: string
description:
type: string
price:
type: number
stock:
type: integer
category:
type: string
 
```> Claude Code 生成的代码：
 
`````python
 
from flask import Flask, request, jsonify
from flask_sqlalchemy import SQLAlchemy
from datetime import datetime
from typing import Optional
 
app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///products.db'
 
db = SQLAlchemy(app)
 
class Product(db.Model):
    """商品模型"""
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(200), nullable=False)
    description = db.Column(db.Text)
    price = db.Column(db.Float, nullable=False)
    stock = db.Column(db.Integer, nullable=False)
    category = db.Column(db.String(100), nullable=False)
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    updated_at = db.Column(db.DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
 
    def to_dict(self):
        """转换为字典"""
        return {
            'id': self.id,
            'name': self.name,
            'description': self.description,
            'price': self.price,
            'stock': self.stock,
            'category': self.category,
            'created_at': self.created_at.isoformat(),
            'updated_at': self.updated_at.isoformat()
        }
 
@app.route('/products', methods=['GET'])
def get_products():
    """获取所有商品"""
    page = request.args.get('page', 1, type=int)
    per_page = request.args.get('per_page', 20, type=int)
 
    pagination = Product.query.paginate(page=page, per_page=per_page)
 
    return jsonify({
        'products': [product.to_dict() for product in pagination.items],
        'total': pagination.total,
        'page': page
    })
 
@app.route('/products', methods=['POST'])
def create_product():
    """创建商品"""
    data = request.get_json()
 
    # 验证必填字段
 
    required_fields = ['name', 'price', 'stock', 'category']
    for field in required_fields:
        if field not in data:
            return jsonify({'error': f'Missing required field: {field}'}), 400
 
    # 验证数据类型
 
    if not isinstance(data['price'], (int, float)) or data['price'] < 0:
        return jsonify({'error': 'Price must be a positive number'}), 400
 
    if not isinstance(data['stock'], int) or data['stock'] < 0:
        return jsonify({'error': 'Stock must be a non-negative integer'}), 400
 
    # 创建商品
 
    product = Product(
        name=data['name'],
        description=data.get('description'),
        price=data['price'],
        stock=data['stock'],
        category=data['category']
    )
 
    db.session.add(product)
    db.session.commit()
 
    return jsonify(product.to_dict()), 201
 
@app.route('/products/<int:product_id>', methods=['GET'])
def get_product(product_id):
    """获取商品详情"""
    product = Product.query.get_or_404(product_id)
    return jsonify(product.to_dict())
 
@app.route('/products/<int:product_id>', methods=['PUT'])
def update_product(product_id):
    """更新商品"""
    product = Product.query.get_or_404(product_id)
    data = request.get_json()
 
    # 更新字段
 
    if 'name' in data:
        product.name = data['name']
 
    if 'description' in data:
        product.description = data['description']
 
    if 'price' in data:
        if not isinstance(data['price'], (int, float)) or data['price'] < 0:
            return jsonify({'error': 'Price must be a positive number'}), 400
        product.price = data['price']
 
    if 'stock' in data:
        if not isinstance(data['stock'], int) or data['stock'] < 0:
            return jsonify({'error': 'Stock must be a non-negative integer'}), 400
        product.stock = data['stock']
 
    if 'category' in data:
        product.category = data['category']
 
    product.updated_at = datetime.utcnow()
    db.session.commit()
 
    return jsonify(product.to_dict())
 
@app.route('/products/<int:product_id>', methods=['DELETE'])
def delete_product(product_id):
    """删除商品"""
    product = Product.query.get_or_404(product_id)
    db.session.delete(product)
    db.session.commit()
 
    return '', 204
 
if __name__ == '__main__':
    with app.app_context():
        db.create_all()
    app.run(debug=True)
 
> **生成的代码包含**:
> - 完整的 CRUD 操作
> - 数据验证
> - 分页功能
> - 错误处理
> - 符合 OpenAPI 规范
 
## 代码补全
 
### 1. 智能方法补全
 
```python
 
# 示例：智能方法补全
 
用户输入：
 
```python
 
class OrderService:
    def __init__(self, db):
        self.db = db
 
    def create_order(self, user_id, items):
        """创建订单"""
        pass
 
Claude Code 自动补全：
 
````python
 
````python
 
class OrderService:
def __init__(self, db):
self.db = db
 
def create_order(self, user_id, items):
"""
创建订单
 
参数:
user_id: 用户 ID
items: 商品列表 [{'product_id': 1, 'quantity': 2}, ...]
 
返回:
订单对象
"""
 # 验证用户
user = self.db.session.query(User).filter_by(id=user_id).first()
if not user:
raise UserNotFoundError(f"User with id {user_id} not found")
 
 # 验证商品
product_ids = [item['product_id'] for item in items]
products = self.db.session.query(Product).filter(
Product.id.in_(product_ids)
).all()
 
product_map = {product.id: product for product in products}
 
for item in items:
if item['product_id'] not in product_map:
raise ProductNotFoundError(
f"Product with id {item['product_id']} not found"
)
 
product = product_map[item['product_id']]
if product.stock < item['quantity']:
raise InsufficientStockError(
f"Insufficient stock for product {product.name}"
)
 
 # 计算总金额
total_amount = sum(
product_map[item['product_id']].price * item['quantity']
for item in items
)
 
 # 创建订单
order = Order(
user_id=user_id,
total_amount=total_amount,
status='pending'
)
 
self.db.session.add(order)
self.db.session.flush()
 
 # 创建订单项
for item in items:
product = product_map[item['product_id']]
order_item = OrderItem(
order_id=order.id,
product_id=item['product_id'],
quantity=item['quantity'],
price=product.price
)
self.db.session.add(order_item)
 
 # 扣减库存
product.stock -= item['quantity']
 
self.db.session.commit()
 
return order
 
def get_order(self, order_id):
"""获取订单详情"""
order = self.db.session.query(Order).filter_by(id=order_id).first()
if not order:
raise OrderNotFoundError(f"Order with id {order_id} not found")
return order
 
def update_order_status(self, order_id, status):
"""更新订单状态"""
order = self.get_order(order_id)
order.status = status
order.updated_at = datetime.utcnow()
self.db.session.commit()
return order
 
def cancel_order(self, order_id):
"""取消订单"""
order = self.get_order(order_id)
 
if order.status in ['paid', 'shipped', 'completed']:
raise InvalidOrderStatusError(
f"Cannot cancel order with status {order.status}"
)
 
 # 恢复库存
for item in order.items:
product = self.db.session.query(Product).filter_by(
id=item.product_id
).first()
if product:
product.stock += item.quantity
 
order.status = 'cancelled'
order.updated_at = datetime.utcnow()
self.db.session.commit()
 
return order
 
def get_user_orders(self, user_id, page=1, per_page=20):
"""获取用户订单列表"""
pagination = self.db.session.query(Order).filter_by(
user_id=user_id
).order_by(
Order.created_at.desc()
).paginate(page=page, per_page=per_page)
 
return pagination
 
```> **补全的内容**:
 
> - 完整的方法实现
> - 数据验证
> - 错误处理
> - 库存管理
> - 相关方法补全
 
### 2. 智能类补全
 
# 示例：智能类补全
用户输入：
 
````python
 
`python
 
```python
class UserRepository:
def __init__(self, db):
self.db = db
 

 
````python
 
```python
from typing import List, Optional
from datetime import datetime
 
class UserRepository:

        def __init__(self, db):
            self.db = db
 
        def find_by_id(self, user_id: int) -> Optional[User]:

            return self.db.session.query(User).filter_by(id=user_id).first()
 
        def find_by_username(self, username: str) -> Optional[User]:

            return self.db.session.query(User).filter_by(username=username).first()
 
        def find_by_email(self, email: str) -> Optional[User]:

            return self.db.session.query(User).filter_by(email=email).first()
 
        def find_all(self, page: int = 1, per_page: int = 20):

            return self.db.session.query(User).paginate(
                page=page,
                per_page=per_page
            )
 
        def create(self, user: User) -> User:

            self.db.session.add(user)
            self.db.session.commit()
            return user
 
        def update(self, user: User) -> User:

            self.db.session.commit()
            return user
 
        def delete(self, user_id: int) -> bool:

            if not user:
                return False
 
            self.db.session.delete(user)
            self.db.session.commit()
            return True
 
        def exists_by_username(self, username: str) -> bool:

            return self.db.session.query(User).filter_by(
                username=username
            ).first() is not None
 
        def exists_by_email(self, email: str) -> bool:

            return self.db.session.query(User).filter_by(
                email=email
            ).first() is not None
 
        def count(self) -> int:

            return self.db.session.query(User).count()
 
        def search(self, keyword: str, page: int = 1, per_page: int = 20):

            return self.db.session.query(User).filter(
                User.username.ilike(f'%{keyword}%') |
                User.email.ilike(f'%{keyword}%')
            ).paginate(page=page, per_page=per_page)