Files
group_fqcd_jr/app/service/risk_scan_service.py
T
lzf_0626 d331c817ac fix(risk): 通知创建失败必须能被区分出来,不再静默返回 0
docs/25 P2「通知失败被吞」。核实后要把定性说得更准一点:它**有** logger.exception,
不是完全静默;问题在于 _create_notifications 失败时 
eturn 0,而"无需通知"
(没有高风险预警、或通知功能关闭)也返回 0 —— 调用方只拿到一个 notification_count,
**分不清"本来就不用通知"和"高风险通知创建失败"**。

风控里这个区别很要紧:通知没发出去等于处置链路的第一环断了,而扫描依旧报"完成"。
这与同一批缺陷里的"定时扫描重启后不再执行"是同一性质 —— 看起来在工作、其实有一环没跑。

改动:
- _create_notifications 返回 (条数, 失败原因),失败原因非空即代表出了问题。
- scan() 在有失败时于返回体里带上
otification_failure,并把 message 改成
  "规则扫描完成,但高风险通知创建失败",让上游与运维都能直接看到。
- **失败仍然不回滚预警**:预警已经生成、比通知重要,不该因为通知写失败就丢掉。

新增 tests/unit/service/test_risk_scan_notification.py(4 条),其中一条专门断言
"两种 0 必须可区分" —— 那是本次修复的全部意义。

ruff / mypy(136 文件) / 616 unit+contract 全绿。
2026-09-11 13:33:41 +08:00

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"""风控规则扫描与预警生成 Service。
扫描只读取交易、资金、持仓、客户、产品和工单事实;写入仅限预警和审计。
规则扫描不负责通知外发,也不在 Web 进程中启动定时任务。
"""
from __future__ import annotations
import asyncio
import logging
from datetime import UTC, date, datetime, timedelta
from decimal import Decimal
from typing import Any
from uuid import uuid4
from sqlalchemy import Select, func, select
from sqlalchemy.ext.asyncio import AsyncSession
from app.core.contracts import RequestContext
from app.core.errors import AgentError, ConflictAgentError
from app.core.timeutil import local_date, local_hour
from app.model.audit import InteractionAudit
from app.model.fund import (
FundCapitalFlow,
FundCustomerProfile,
FundProduct,
FundRiskAlert,
FundTransaction,
)
from app.model.risk import RiskLoginRecord, RiskUser, RiskWorkOrder
from app.service.authorization_service import AuthorizationService
from app.service.risk_notification_service import RiskNotificationService
HIGH_RISK = "高"
MEDIUM_RISK = "中"
LOW_RISK = "低"
RISK_ORDER = {LOW_RISK: 0, MEDIUM_RISK: 1, HIGH_RISK: 2}
_scan_lock = asyncio.Lock()
logger = logging.getLogger(__name__)
class RiskScanBusyError(ConflictAgentError):
"""同一进程内已有扫描任务执行。"""
class RiskScanError(AgentError):
"""规则扫描失败。"""
code = "AGENT_INTERNAL_ERROR"
status_code = 500
class RiskRuleEngine:
"""五条当前启用风控规则的只读判定和预警构造。"""
def __init__(self, session: AsyncSession) -> None:
self.session = session
self._handler_id: int | None = None
async def refresh_alerts(self) -> list[FundRiskAlert]:
self._handler_id = await self._risk_operator_id()
alerts: list[FundRiskAlert] = []
alerts.extend(await self._fast_in_fast_out())
alerts.extend(await self._suitability_mismatch())
alerts.extend(await self._elderly_redemption())
alerts.extend(await self._low_risk_night_trade())
alerts.extend(await self._auto_investment_false_positive())
alerts = self._merge_same_transaction_alerts(alerts)
for alert in alerts:
self.session.add(alert)
self.session.add(InteractionAudit(
actor_type="system",
target_customer_id=alert.customer_id,
portal="api",
action_type="risk_alert_created",
detail={"alert_no": alert.alert_no, "rule_codes": alert.trigger_rule_codes},
created_at=datetime.now(UTC).replace(tzinfo=None),
))
await self.session.flush()
return alerts
async def _fast_in_fast_out(self) -> list[FundRiskAlert]:
alerts: list[FundRiskAlert] = []
transactions = await self._scalars(
select(FundTransaction).where(FundTransaction.transaction_type == "赎回")
)
for transaction in transactions:
if transaction.confirmed_at is None or transaction.amount is None:
continue
capital = await self.session.scalar(
select(FundCapitalFlow)
.where(
FundCapitalFlow.customer_id == transaction.customer_id,
FundCapitalFlow.flow_type == "入金",
FundCapitalFlow.status == "成功",
FundCapitalFlow.settled_at.is_not(None),
FundCapitalFlow.settled_at <= transaction.confirmed_at,
FundCapitalFlow.settled_at >= transaction.confirmed_at - timedelta(days=3),
)
.order_by(FundCapitalFlow.settled_at.desc())
.limit(1)
)
if capital is None or capital.amount <= 0:
continue
ratio = Decimal(transaction.amount) / Decimal(capital.amount)
if ratio >= Decimal("0.8") and transaction.amount >= 500000 and not await self._exists(
transaction.id, "RW-003"
):
alerts.append(self._build_alert(
transaction=transaction,
alert_type="大额快进快出",
level=HIGH_RISK,
rules=["RW-003"],
summary=(
f"3 日内入金 {capital.amount:.0f} 元后赎回 "
f"{transaction.amount:.0f} 元,赎回比例 {ratio:.2%}。"
),
priority=98,
event_status="正在发生",
evidence={
"product_id": transaction.product_id,
"capital_flow_id": capital.id,
"flow_no": capital.flow_no,
"ratio": str(ratio),
},
))
return alerts
async def _suitability_mismatch(self) -> list[FundRiskAlert]:
alerts: list[FundRiskAlert] = []
transactions = await self._scalars(
select(FundTransaction).where(FundTransaction.transaction_type == "申购")
)
for transaction in transactions:
customer = await self.session.get(RiskUser, transaction.customer_id)
product = await self.session.get(FundProduct, transaction.product_id)
work_order = (
await self.session.get(RiskWorkOrder, transaction.work_order_id)
if transaction.work_order_id is not None
else None
)
if (
customer is None
or product is None
or not customer.investor_type
or await self._exists(transaction.id, "RW-007")
):
continue
gap = _level_value(product.risk_level, "R") - _level_value(customer.investor_type, "C")
missing_trace = (
(
product.risk_disclosure_required
and (
work_order is None
or work_order.risk_disclosure_ack_at is None
)
)
or (
product.second_confirmation_required
and (
work_order is None
or work_order.second_confirmation_at is None
)
)
or (
product.recording_required
and (work_order is None or not work_order.recording_reference)
)
)
if gap > 0 and missing_trace:
level = HIGH_RISK if gap >= 2 else MEDIUM_RISK
alerts.append(self._build_alert(
transaction=transaction,
alert_type="适当性错配",
level=level,
rules=["RW-007"],
summary=(
f"{customer.investor_type} 客户购买 "
f"{product.risk_level} 产品,交易留痕不完整。"
),
priority=90 if level == HIGH_RISK else 70,
event_status="刚刚发生",
evidence={
"product_id": product.id,
"level_gap": gap,
"work_order_id": transaction.work_order_id,
},
))
return alerts
async def _elderly_redemption(self) -> list[FundRiskAlert]:
alerts: list[FundRiskAlert] = []
transactions = await self._scalars(
select(FundTransaction).where(FundTransaction.transaction_type == "赎回")
)
for transaction in transactions:
if transaction.confirmed_at is None or transaction.amount is None:
continue
profile = await self.session.get(FundCustomerProfile, transaction.customer_id)
age = _age(profile.birth_date) if profile else 0
if profile is None or age < 65 or transaction.amount < 300000:
continue
average = await self.session.scalar(
select(func.avg(FundTransaction.amount)).where(
FundTransaction.customer_id == transaction.customer_id,
FundTransaction.id != transaction.id,
FundTransaction.confirmed_at >= transaction.confirmed_at - timedelta(days=365),
)
)
if average is None or transaction.amount < Decimal(average) * 3:
continue
login = await self.session.scalar(
select(RiskLoginRecord)
.where(
RiskLoginRecord.user_id == transaction.customer_id,
RiskLoginRecord.login_result == "成功",
RiskLoginRecord.login_at <= transaction.confirmed_at,
)
.order_by(RiskLoginRecord.login_at.desc())
.limit(1)
)
if login is not None and not login.is_common_device and not await self._exists(
transaction.id, "RW-012"
):
alerts.append(self._build_alert(
transaction=transaction,
alert_type="老年客户异常大额赎回",
level=HIGH_RISK,
rules=["RW-012"],
summary=(
f"{age} 岁客户赎回 {transaction.amount:.0f} 元,"
"超过历史均值且使用非常用设备。"
),
priority=96,
event_status="正在发生",
evidence={
"product_id": transaction.product_id,
"age": age,
"device_id": login.device_id,
},
))
return alerts
async def _low_risk_night_trade(self) -> list[FundRiskAlert]:
alerts: list[FundRiskAlert] = []
for transaction in await self._scalars(select(FundTransaction)):
if (
transaction.confirmed_at is not None
# 必须按**北京时间**判断"凌晨":库里存 UTC,直接取 .hour 会让
# [0,6) UTC 变成北京 08:00–14:00,整条规则判的是上午(docs/25 P1 #6)。
and 0 <= local_hour(transaction.confirmed_at) < 6
and transaction.amount is not None
and transaction.amount <= 10000
and not await self._exists(transaction.id, "RW-015")
):
alerts.append(self._build_alert(
transaction=transaction,
alert_type="非正常时段小额操作",
level=LOW_RISK,
rules=["RW-015"],
summary=f"凌晨时段发生 {transaction.amount:.0f} 元交易,金额较小。",
priority=20,
event_status="盘后预警",
evidence={
"product_id": transaction.product_id,
"hour": transaction.confirmed_at.hour,
},
))
return alerts
async def _auto_investment_false_positive(self) -> list[FundRiskAlert]:
alerts: list[FundRiskAlert] = []
transactions = await self._scalars(
select(FundTransaction).where(FundTransaction.work_order_id.is_not(None))
)
for transaction in transactions:
work_order = await self.session.get(RiskWorkOrder, transaction.work_order_id)
if (
work_order is not None
and work_order.channel in {"定投", "自动定投"}
and not await self._exists(transaction.id, "RW-018")
):
alerts.append(self._build_alert(
transaction=transaction,
alert_type="频繁交易初筛",
level=LOW_RISK,
rules=["RW-018"],
summary="近 30 天交易频率较高,但交易来自有效定投工单。",
priority=10,
event_status="盘后预警",
evidence={
"product_id": transaction.product_id,
"work_order_no": work_order.work_order_no,
"channel": work_order.channel,
},
))
return alerts
def _build_alert(
self,
*,
transaction: FundTransaction,
alert_type: str,
level: str,
rules: list[str],
summary: str,
priority: int,
event_status: str,
evidence: dict[str, object],
) -> FundRiskAlert:
now = datetime.now(UTC).replace(tzinfo=None)
return FundRiskAlert(
id=_new_alert_id(),
alert_no=f"AL{uuid4().hex[:12].upper()}",
customer_id=transaction.customer_id,
related_transaction_id=transaction.id,
related_order_id=transaction.order_id,
related_work_order_id=transaction.work_order_id,
alert_type=alert_type,
alert_level=level,
trigger_rule_codes=rules,
evidence_summary=summary,
evidence_snapshot=evidence,
priority_score=priority,
event_status=event_status,
status="待处理",
ack_status="未确认",
handler_id=self._handler_id,
due_at=now + timedelta(minutes=30) if level == HIGH_RISK else None,
is_escalated=0,
created_at=now,
updated_at=now,
)
async def _exists(self, transaction_id: int, rule_code: str) -> bool:
return await self.session.scalar(
select(FundRiskAlert.id).where(
FundRiskAlert.related_transaction_id == transaction_id,
FundRiskAlert.trigger_rule_codes.contains([rule_code]),
)
) is not None
async def _risk_operator_id(self) -> int | None:
value = await self.session.scalar(
select(RiskUser.id)
.where(RiskUser.employee_role == "risk_operator", RiskUser.status == "正常")
.order_by(RiskUser.id.asc())
.limit(1)
)
return int(value) if value is not None else None
async def _scalars(self, statement: Select[Any]) -> list[Any]:
result = await self.session.scalars(statement)
return list(result.all())
@staticmethod
def _merge_same_transaction_alerts(alerts: list[FundRiskAlert]) -> list[FundRiskAlert]:
grouped: dict[int | None, list[FundRiskAlert]] = {}
for alert in alerts:
grouped.setdefault(alert.related_transaction_id, []).append(alert)
merged: list[FundRiskAlert] = []
for transaction_id, items in grouped.items():
if transaction_id is None or len(items) == 1:
merged.extend(items)
continue
primary = max(items, key=lambda item: item.priority_score)
primary.trigger_rule_codes = list(
dict.fromkeys(code for item in items for code in item.trigger_rule_codes)
)
primary.evidence_summary = ";".join(item.evidence_summary for item in items)
primary.evidence_snapshot = {
"product_id": primary.evidence_snapshot.get("product_id"),
"merged_alerts": [
{"alert_type": item.alert_type, "evidence": item.evidence_snapshot}
for item in items
],
}
primary.alert_level = max(
(item.alert_level for item in items),
key=RISK_ORDER.__getitem__,
)
primary.priority_score = max(item.priority_score for item in items)
merged.append(primary)
return merged
class RiskScanService:
def __init__(
self,
session: AsyncSession,
*,
rule_engine: RiskRuleEngine | None = None,
notification_service: RiskNotificationService | None = None,
notification_enabled: bool = True,
notification_email: str | None = None,
mail_enabled: bool = False,
) -> None:
self.session = session
self.rule_engine = rule_engine or RiskRuleEngine(session)
self.notification_service = notification_service or RiskNotificationService(session)
self.notification_enabled = notification_enabled
self.notification_email = notification_email
self.mail_enabled = mail_enabled
async def scan(self, context: RequestContext) -> dict[str, int | str]:
await AuthorizationService.require(context, "risk:alert:scan")
if _scan_lock.locked():
raise RiskScanBusyError("规则扫描正在执行,请稍后重试")
async with _scan_lock:
try:
alerts = await self.rule_engine.refresh_alerts()
notification_count, notification_failure = await self._create_notifications(alerts)
await self.session.commit()
except Exception as error:
await self.session.rollback()
raise RiskScanError("规则扫描失败") from error
result: dict[str, int | str] = {
"message": "规则扫描完成",
"created_count": len(alerts),
"high_risk_count": sum(alert.alert_level == HIGH_RISK for alert in alerts),
"notification_count": notification_count,
}
if notification_failure:
# 通知失败**不回滚**预警(预警已经生成、比通知重要),但必须让调用方看见。
# 原先这里无处可查:外面只拿到 notification_count=0,分不清"这批预警本来
# 就不用通知"和"高风险通知创建失败了"——而后者意味着处置链路的第一环断了,
# 扫描却报"完成"。
result["notification_failure"] = notification_failure
result["message"] = "规则扫描完成,但高风险通知创建失败"
return result
async def _create_notifications(self, alerts: list[FundRiskAlert]) -> tuple[int, str]:
"""为高风险预警创建通知记录,返回 `(创建条数, 失败原因)`。
**失败原因必须交给调用方。** 原先这里失败时 `return 0`,而"无需通知"(没有高风险
预警、或通知功能关闭)也返回 0 —— 外面根本分不清两者。风控里这个区别很要紧:
通知没发出去等于处置链路的第一环断了,而扫描依旧报"完成"。
失败**不回滚**预警本身:预警已经生成、比通知重要,不该因为通知写失败就丢掉。
"""
if not self.notification_enabled:
return 0, ""
high_risk = [alert for alert in alerts if alert.alert_level == HIGH_RISK]
if not high_risk:
return 0, ""
try:
async with self.session.begin_nested():
count = 0
for alert in high_risk:
title = f"高风险预警:{alert.alert_type}"
self.notification_service.create_in_app(
alert,
receiver_user_id=alert.handler_id,
title=title,
content=alert.evidence_summary,
)
count += 1
if self.notification_email:
self.notification_service.create_mail_record(
alert,
receiver_email=self.notification_email,
title=title,
content=alert.evidence_summary,
mail_enabled=self.mail_enabled,
)
count += 1
return count, ""
except Exception as error:
logger.exception("高风险通知记录创建失败,预警扫描继续提交")
return 0, f"{type(error).__name__}: {error}"[:200]
def _new_alert_id() -> int:
"""生成非零 63 位正整数;预警表主键不自增。"""
return uuid4().int & ((1 << 63) - 1) or 1
def _age(birth_date: date | None) -> int:
if birth_date is None:
return 0
# 用**北京时间**的今天:原先用 UTC 日期,而研判侧用服务器 date.today(),
# 两处口径不一致会让同一客户在生日边界上差一岁(docs/25 P1 #6)。
today = local_date(datetime.now(UTC))
return today.year - birth_date.year - (
(today.month, today.day) < (birth_date.month, birth_date.day)
)
def _level_value(level: str, prefix: str) -> int:
return int(level.replace(prefix, ""))