XingHuo/app/api/simulate.py

"""模拟交易网关路由（PRD FR-1 · 薄路由，不含业务）。

鉴权：`Depends(get_auth_context)`（B6 回挂，评审 P2-2）——一期接受
risk_demo 演示账号或客户本人（auth.customer_id == 请求 customer_id，
PRD FR-1 §鉴权）；越权经 deps.deny 审计后 403。T-01 后工厂内部换 JWT。
trace：B7 中间件贯通；B7 前由 service 层 ensure_trace 兜底。
挂载：B7 集成 main.py（当前仅 TestClient 独立挂 router 验证）。
统一响应外壳：utils/response.py 为占位（P1 任务），落地点挂账 B7（届时
simulate/risk 一并包裹，本路由返回体不变）。
"""

from __future__ import annotations

from decimal import Decimal

from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel, Field

from app.api.deps import AuthContext, deny, get_auth_context
from app.gateway.trade_gateway import UnsupportedTradeType, submit_trade
from app.repository.risk_repository import RiskRepository

router = APIRouter(prefix="/api/simulate", tags=["simulate"])


def _repo() -> RiskRepository:
    """审计仓储（deny 留痕用；测试 monkeypatch 点）。"""
    return RiskRepository()


class TradeRequest(BaseModel):
    customer_id: str = Field(..., min_length=1)
    product_id: str = Field(..., min_length=1)
    trade_type: str = Field(..., max_length=16, description="subscribe | redeem；convert 显式拒绝")
    amount: Decimal = Field(..., gt=0, description="交易金额（元），必须为正数")


@router.post("/trade")
def submit_trade_api(req: TradeRequest, auth: AuthContext = Depends(get_auth_context)) -> dict:
    """模拟交易（FR-1）：适当性阻断或放行+引擎判定，返回 blocked + trade_id。"""
    if not (auth.has_role("risk_demo") or (auth.is_customer() and auth.customer_id == req.customer_id)):
        deny(
            auth, "AUTH_403_ROLE", _repo(),
            customer_id=req.customer_id, message="risk_demo or owner customer only",
        )
    try:
        return submit_trade(req.model_dump())
    except UnsupportedTradeType as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    except LookupError as exc:  # NotFoundError 亦为其子类；已统一（B6 评审 P3-5）
        raise HTTPException(status_code=404, detail=str(exc)) from exc