feat: 新增告警、成本、配额、微信模块及缓存服务

- 新增告警模块 (alerts): 告警规则配置与触发
- 新增成本管理模块 (cost): 成本统计与分析
- 新增配额模块 (quota): 配额管理与限制
- 新增微信模块 (wechat): 微信相关功能接口
- 新增缓存服务 (cache): Redis 缓存封装
- 新增请求日志中间件 (request_logger)
- 新增异常处理和链路追踪中间件
- 更新 dashboard 前端展示
- 更新 SDK stats_client 功能

backend/app/services/cost.py

@@ -0,0 +1,420 @@
+"""费用计算服务"""
+import logging
+from datetime import datetime
+from decimal import Decimal
+from typing import Optional, Dict, List
+from functools import lru_cache
+
+from sqlalchemy.orm import Session
+from sqlalchemy import func
+
+from ..models.pricing import ModelPricing, TenantBilling
+from ..models.stats import AICallEvent
+from .cache import get_cache
+
+logger = logging.getLogger(__name__)
+
+
+class CostCalculator:
+    """费用计算器
+    
+    使用示例:
+        calculator = CostCalculator(db)
+        
+        # 计算单次调用费用
+        cost = calculator.calculate_cost("gpt-4", input_tokens=100, output_tokens=200)
+        
+        # 生成月度账单
+        billing = calculator.generate_monthly_billing("qiqi", "2026-01")
+    """
+    
+    # 默认模型价格（当数据库中无配置时使用）
+    DEFAULT_PRICING = {
+        # OpenAI
+        "gpt-4": {"input": 0.21, "output": 0.42},  # 元/1K tokens
+        "gpt-4-turbo": {"input": 0.07, "output": 0.21},
+        "gpt-4o": {"input": 0.035, "output": 0.105},
+        "gpt-4o-mini": {"input": 0.00105, "output": 0.0042},
+        "gpt-3.5-turbo": {"input": 0.0035, "output": 0.014},
+        
+        # Anthropic
+        "claude-3-opus": {"input": 0.105, "output": 0.525},
+        "claude-3-sonnet": {"input": 0.021, "output": 0.105},
+        "claude-3-haiku": {"input": 0.00175, "output": 0.00875},
+        "claude-3.5-sonnet": {"input": 0.021, "output": 0.105},
+        
+        # 国内模型
+        "qwen-max": {"input": 0.02, "output": 0.06},
+        "qwen-plus": {"input": 0.004, "output": 0.012},
+        "qwen-turbo": {"input": 0.002, "output": 0.006},
+        "glm-4": {"input": 0.01, "output": 0.01},
+        "glm-4-flash": {"input": 0.0001, "output": 0.0001},
+        "deepseek-chat": {"input": 0.001, "output": 0.002},
+        "deepseek-coder": {"input": 0.001, "output": 0.002},
+        
+        # 默认
+        "default": {"input": 0.01, "output": 0.03}
+    }
+    
+    def __init__(self, db: Session):
+        self.db = db
+        self._cache = get_cache()
+        self._pricing_cache: Dict[str, ModelPricing] = {}
+    
+    def get_model_pricing(self, model_name: str) -> Optional[ModelPricing]:
+        """获取模型价格配置
+        
+        Args:
+            model_name: 模型名称
+        
+        Returns:
+            ModelPricing实例或None
+        """
+        # 尝试从缓存获取
+        cache_key = f"pricing:{model_name}"
+        cached = self._cache.get(cache_key)
+        if cached:
+            return self._dict_to_pricing(cached)
+        
+        # 从数据库查询
+        pricing = self.db.query(ModelPricing).filter(
+            ModelPricing.model_name == model_name,
+            ModelPricing.status == 1
+        ).first()
+        
+        if pricing:
+            # 缓存1小时
+            self._cache.set(cache_key, self._pricing_to_dict(pricing), ttl=3600)
+            return pricing
+        
+        return None
+    
+    def _pricing_to_dict(self, pricing: ModelPricing) -> dict:
+        return {
+            "model_name": pricing.model_name,
+            "input_price_per_1k": str(pricing.input_price_per_1k),
+            "output_price_per_1k": str(pricing.output_price_per_1k),
+            "fixed_price_per_call": str(pricing.fixed_price_per_call),
+            "pricing_type": pricing.pricing_type
+        }
+    
+    def _dict_to_pricing(self, d: dict) -> ModelPricing:
+        pricing = ModelPricing()
+        pricing.model_name = d.get("model_name")
+        pricing.input_price_per_1k = Decimal(d.get("input_price_per_1k", "0"))
+        pricing.output_price_per_1k = Decimal(d.get("output_price_per_1k", "0"))
+        pricing.fixed_price_per_call = Decimal(d.get("fixed_price_per_call", "0"))
+        pricing.pricing_type = d.get("pricing_type", "token")
+        return pricing
+    
+    def calculate_cost(
+        self,
+        model_name: str,
+        input_tokens: int = 0,
+        output_tokens: int = 0,
+        call_count: int = 1
+    ) -> Decimal:
+        """计算调用费用
+        
+        Args:
+            model_name: 模型名称
+            input_tokens: 输入token数
+            output_tokens: 输出token数
+            call_count: 调用次数
+        
+        Returns:
+            费用（元）
+        """
+        # 尝试获取数据库配置
+        pricing = self.get_model_pricing(model_name)
+        
+        if pricing:
+            if pricing.pricing_type == 'call':
+                return pricing.fixed_price_per_call * call_count
+            elif pricing.pricing_type == 'hybrid':
+                token_cost = (
+                    pricing.input_price_per_1k * Decimal(input_tokens) / 1000 +
+                    pricing.output_price_per_1k * Decimal(output_tokens) / 1000
+                )
+                call_cost = pricing.fixed_price_per_call * call_count
+                return token_cost + call_cost
+            else:  # token
+                return (
+                    pricing.input_price_per_1k * Decimal(input_tokens) / 1000 +
+                    pricing.output_price_per_1k * Decimal(output_tokens) / 1000
+                )
+        
+        # 使用默认价格
+        default_prices = self.DEFAULT_PRICING.get(model_name) or self.DEFAULT_PRICING.get("default")
+        input_price = Decimal(str(default_prices["input"]))
+        output_price = Decimal(str(default_prices["output"]))
+        
+        return (
+            input_price * Decimal(input_tokens) / 1000 +
+            output_price * Decimal(output_tokens) / 1000
+        )
+    
+    def calculate_event_cost(self, event: AICallEvent) -> Decimal:
+        """计算单个事件的费用
+        
+        Args:
+            event: AI调用事件
+        
+        Returns:
+            费用（元）
+        """
+        return self.calculate_cost(
+            model_name=event.model or "default",
+            input_tokens=event.input_tokens or 0,
+            output_tokens=event.output_tokens or 0
+        )
+    
+    def update_event_costs(self, start_date: str = None, end_date: str = None) -> int:
+        """批量更新事件费用
+        
+        对于cost为0或NULL的事件，重新计算费用
+        
+        Args:
+            start_date: 开始日期，格式 YYYY-MM-DD
+            end_date: 结束日期，格式 YYYY-MM-DD
+        
+        Returns:
+            更新的记录数
+        """
+        query = self.db.query(AICallEvent).filter(
+            (AICallEvent.cost == None) | (AICallEvent.cost == 0)
+        )
+        
+        if start_date:
+            query = query.filter(AICallEvent.created_at >= start_date)
+        if end_date:
+            query = query.filter(AICallEvent.created_at <= end_date + " 23:59:59")
+        
+        events = query.all()
+        updated = 0
+        
+        for event in events:
+            try:
+                cost = self.calculate_event_cost(event)
+                event.cost = cost
+                updated += 1
+            except Exception as e:
+                logger.error(f"Failed to calculate cost for event {event.id}: {e}")
+        
+        self.db.commit()
+        logger.info(f"Updated {updated} event costs")
+        
+        return updated
+    
+    def generate_monthly_billing(
+        self,
+        tenant_id: str,
+        billing_month: str
+    ) -> TenantBilling:
+        """生成月度账单
+        
+        Args:
+            tenant_id: 租户ID
+            billing_month: 账单月份，格式 YYYY-MM
+        
+        Returns:
+            TenantBilling实例
+        """
+        # 检查是否已存在
+        existing = self.db.query(TenantBilling).filter(
+            TenantBilling.tenant_id == tenant_id,
+            TenantBilling.billing_month == billing_month
+        ).first()
+        
+        if existing:
+            billing = existing
+        else:
+            billing = TenantBilling(
+                tenant_id=tenant_id,
+                billing_month=billing_month
+            )
+            self.db.add(billing)
+        
+        # 计算统计数据
+        start_date = f"{billing_month}-01"
+        year, month = billing_month.split("-")
+        if int(month) == 12:
+            end_date = f"{int(year)+1}-01-01"
+        else:
+            end_date = f"{year}-{int(month)+1:02d}-01"
+        
+        # 聚合查询
+        stats = self.db.query(
+            func.count(AICallEvent.id).label('total_calls'),
+            func.coalesce(func.sum(AICallEvent.input_tokens), 0).label('total_input'),
+            func.coalesce(func.sum(AICallEvent.output_tokens), 0).label('total_output'),
+            func.coalesce(func.sum(AICallEvent.cost), 0).label('total_cost')
+        ).filter(
+            AICallEvent.tenant_id == tenant_id,
+            AICallEvent.created_at >= start_date,
+            AICallEvent.created_at < end_date
+        ).first()
+        
+        billing.total_calls = stats.total_calls or 0
+        billing.total_input_tokens = int(stats.total_input or 0)
+        billing.total_output_tokens = int(stats.total_output or 0)
+        billing.total_cost = stats.total_cost or Decimal("0")
+        
+        # 按模型统计
+        model_stats = self.db.query(
+            AICallEvent.model,
+            func.coalesce(func.sum(AICallEvent.cost), 0).label('cost')
+        ).filter(
+            AICallEvent.tenant_id == tenant_id,
+            AICallEvent.created_at >= start_date,
+            AICallEvent.created_at < end_date
+        ).group_by(AICallEvent.model).all()
+        
+        billing.cost_by_model = {
+            m.model or "unknown": float(m.cost) for m in model_stats
+        }
+        
+        # 按应用统计
+        app_stats = self.db.query(
+            AICallEvent.app_code,
+            func.coalesce(func.sum(AICallEvent.cost), 0).label('cost')
+        ).filter(
+            AICallEvent.tenant_id == tenant_id,
+            AICallEvent.created_at >= start_date,
+            AICallEvent.created_at < end_date
+        ).group_by(AICallEvent.app_code).all()
+        
+        billing.cost_by_app = {
+            a.app_code or "unknown": float(a.cost) for a in app_stats
+        }
+        
+        self.db.commit()
+        self.db.refresh(billing)
+        
+        return billing
+    
+    def get_cost_summary(
+        self,
+        tenant_id: str = None,
+        start_date: str = None,
+        end_date: str = None
+    ) -> Dict:
+        """获取费用汇总
+        
+        Args:
+            tenant_id: 租户ID（可选）
+            start_date: 开始日期
+            end_date: 结束日期
+        
+        Returns:
+            费用汇总字典
+        """
+        query = self.db.query(
+            func.count(AICallEvent.id).label('total_calls'),
+            func.coalesce(func.sum(AICallEvent.input_tokens), 0).label('total_input'),
+            func.coalesce(func.sum(AICallEvent.output_tokens), 0).label('total_output'),
+            func.coalesce(func.sum(AICallEvent.cost), 0).label('total_cost')
+        )
+        
+        if tenant_id:
+            query = query.filter(AICallEvent.tenant_id == tenant_id)
+        if start_date:
+            query = query.filter(AICallEvent.created_at >= start_date)
+        if end_date:
+            query = query.filter(AICallEvent.created_at <= end_date + " 23:59:59")
+        
+        stats = query.first()
+        
+        return {
+            "total_calls": stats.total_calls or 0,
+            "total_input_tokens": int(stats.total_input or 0),
+            "total_output_tokens": int(stats.total_output or 0),
+            "total_cost": float(stats.total_cost or 0)
+        }
+    
+    def get_cost_by_tenant(
+        self,
+        start_date: str = None,
+        end_date: str = None
+    ) -> List[Dict]:
+        """按租户统计费用
+        
+        Returns:
+            租户费用列表
+        """
+        query = self.db.query(
+            AICallEvent.tenant_id,
+            func.count(AICallEvent.id).label('calls'),
+            func.coalesce(func.sum(AICallEvent.cost), 0).label('cost')
+        )
+        
+        if start_date:
+            query = query.filter(AICallEvent.created_at >= start_date)
+        if end_date:
+            query = query.filter(AICallEvent.created_at <= end_date + " 23:59:59")
+        
+        results = query.group_by(AICallEvent.tenant_id).order_by(
+            func.sum(AICallEvent.cost).desc()
+        ).all()
+        
+        return [
+            {
+                "tenant_id": r.tenant_id,
+                "calls": r.calls,
+                "cost": float(r.cost)
+            }
+            for r in results
+        ]
+    
+    def get_cost_by_model(
+        self,
+        tenant_id: str = None,
+        start_date: str = None,
+        end_date: str = None
+    ) -> List[Dict]:
+        """按模型统计费用
+        
+        Returns:
+            模型费用列表
+        """
+        query = self.db.query(
+            AICallEvent.model,
+            func.count(AICallEvent.id).label('calls'),
+            func.coalesce(func.sum(AICallEvent.input_tokens), 0).label('input_tokens'),
+            func.coalesce(func.sum(AICallEvent.output_tokens), 0).label('output_tokens'),
+            func.coalesce(func.sum(AICallEvent.cost), 0).label('cost')
+        )
+        
+        if tenant_id:
+            query = query.filter(AICallEvent.tenant_id == tenant_id)
+        if start_date:
+            query = query.filter(AICallEvent.created_at >= start_date)
+        if end_date:
+            query = query.filter(AICallEvent.created_at <= end_date + " 23:59:59")
+        
+        results = query.group_by(AICallEvent.model).order_by(
+            func.sum(AICallEvent.cost).desc()
+        ).all()
+        
+        return [
+            {
+                "model": r.model or "unknown",
+                "calls": r.calls,
+                "input_tokens": int(r.input_tokens),
+                "output_tokens": int(r.output_tokens),
+                "cost": float(r.cost)
+            }
+            for r in results
+        ]
+
+
+# 便捷函数
+def calculate_cost(
+    db: Session,
+    model_name: str,
+    input_tokens: int = 0,
+    output_tokens: int = 0
+) -> Decimal:
+    """快速计算费用"""
+    calculator = CostCalculator(db)
+    return calculator.calculate_cost(model_name, input_tokens, output_tokens)