rakuten-api/app/trading/worker/runner.py

"""worker 主循环与每任务执行流

主循环（规格 §6）：

    while running:
        task = await gateway.lease(worker_id, wait=30)
        if task is None:
            continue

        if local_db.has_finished(task.task_id):              # 本地幂等闸门
            await gateway.report(...); continue

        if task.lease_count > 1:                             # 恢复领取
            verdict = await verify_on_site(task)
            if verdict.already_ordered: await report(...); continue
            if verdict.unknown: await report(needs_human); continue

        async with renew_lease_every(60):
            await execute(task)

每个动作的顺序固定为：动作 → 落证据 → 写本地 SQLite → 回报 gateway。
顺序不能颠倒——先落证据再回报，保证服务器上看到的状态一定有本地证据可查。
"""
from __future__ import annotations

import asyncio
import contextlib
import logging
from typing import TYPE_CHECKING

from app.shared.errors import AppError, OrderGuardError
from app.shared.task_state import OrderState, TaskStatus
from app.trading.worker import verify
from app.trading.worker.client import GatewayClient
from app.trading.worker.evidence import EvidenceStore
from app.trading.worker.local_db import LocalDB
from app.trading.worker.models import LeaseTask
from app.trading.worker.site_interact import SiteInteractor

if TYPE_CHECKING:
    from app.shared.config import Settings

logger = logging.getLogger(__name__)


def _coerce_state(value: str | None) -> OrderState:
    """把网关返回的 state 字符串安全地包成 OrderState；None 或非法值回落到 CREATED"""
    if not value:
        return OrderState.CREATED
    try:
        return OrderState(value)
    except ValueError:
        logger.warning("未知的 order state 字符串，回落到 CREATED：%s", value)
        return OrderState.CREATED


class WorkerRunner:
    """worker 主循环与执行流

    持有 gateway 客户端、本地 DB、证据存储。`run()` 是常驻 asyncio 任务，
    `handle()` 处理单个任务，`execute()` 是站点交互的实际调度（当前多数步骤未实现）。
    """

    def __init__(
        self,
        *,
        settings: "Settings",
        gateway_client: GatewayClient,
        local_db: LocalDB,
        evidence: EvidenceStore,
        site: SiteInteractor,
    ):
        self._settings = settings
        self._gateway = gateway_client
        self._db = local_db
        self._evidence = evidence
        self._site = site
        self._running = False

    def stop(self) -> None:
        self._running = False

    @property
    def worker_id(self) -> str:
        return self._settings.worker_id_effective

    # ---- 主循环 ----

    async def run(self) -> None:
        """常驻循环：长轮询领任务，按 §6 调度"""
        self._running = True
        logger.info("worker 启动：worker_id=%s", self.worker_id)
        while self._running:
            try:
                task = await self._gateway.lease(self.worker_id, wait=30)
            except AppError as exc:
                logger.warning("lease 失败：%s (err=%s)", exc.message, exc.err_code)
                await asyncio.sleep(5)
                continue
            except Exception:  # noqa: BLE001
                logger.exception("lease 异常")
                await asyncio.sleep(5)
                continue

            if task is None:
                continue

            try:
                await self.handle(task)
            except Exception:  # noqa: BLE001
                # 任何未预期的异常都不应让 worker 退出
                logger.exception("handle 任务异常：task_id=%s", task.task_id)

    # ---- 单任务调度 ----

    async def handle(self, task: LeaseTask) -> None:
        """单任务调度入口：本地幂等闸门 → 恢复核对 → 执行"""
        # 本地幂等闸门：之前已完成过的任务不再执行
        if await self._db.has_finished(task.task_id):
            final_state = await self._db.final_state(task.task_id)
            logger.info(
                "本地已完成，补报终态：task_id=%s state=%s", task.task_id, final_state
            )
            await self._report_safe(
                task,
                state=_coerce_state(final_state),
                detail="本地已完成，补报避免重复执行",
                terminal=True,
            )
            return

        # 恢复领取：lease_count > 1 表示 stale → reclaim，必须先核对站点订单
        if task.lease_count > 1:
            await self._handle_recovery(task)
            return

        # 常规执行
        await self._execute_with_renewal(task)

    async def _handle_recovery(self, task: LeaseTask) -> None:
        """lease_count > 1 的恢复路径：先核对，不直接执行"""
        logger.warning(
            "恢复领取（lease_count=%s），先核对站点订单：task_id=%s",
            task.lease_count,
            task.task_id,
        )
        verdict = await verify.verify_on_site(task)
        if verdict.verdict == verify.VerifyVerdict.ALREADY_ORDERED:
            await self._report_safe(
                task,
                state=OrderState.ORDERED,
                site_order_id=verdict.site_order_id,
                detail=f"核对结论：已下单（{verdict.detail}）",
                terminal=True,
                terminal_status=TaskStatus.SUCCEEDED,
            )
            await self._db.ensure_started(task.task_id, task.site, task.intent)
            await self._db.mark_finished(task.task_id, OrderState.ORDERED.value)
            return

        # NOT_ORDERED 也走 needs_human：当前 verify 桩不会返回这个值，但留接口给
        # 未来真正能可靠核对时——那时再决定 NOT_ORDERED 是否直接重新执行
        await self._report_safe(
            task,
            state=_coerce_state(task.known_state),
            detail=f"恢复核对无法定论：{verdict.detail}",
            terminal=True,
            terminal_status=TaskStatus.NEEDS_HUMAN,
        )

    # ---- 常规执行 ----

    async def _execute_with_renewal(self, task: LeaseTask) -> None:
        """在租约自动续期的上下文里执行任务"""
        async with self._renew_lease_every(task, interval=60):
            try:
                await self.execute(task)
            except NotImplementedError as exc:
                # 站点交互未实现（规格 §10）：上报 needs_human，不视为 worker 失败
                logger.warning(
                    "站点交互未实现，转 needs_human：task_id=%s what=%s",
                    task.task_id,
                    exc,
                )
                await self._report_safe(
                    task,
                    state=_coerce_state(task.known_state),
                    detail=f"站点交互未实现：{exc}",
                    terminal=True,
                    terminal_status=TaskStatus.NEEDS_HUMAN,
                )
            except OrderGuardError as exc:
                # 金额守卫等闸门拦截：上报 needs_human，站点侧无提交动作
                logger.warning(
                    "下单闸门拦截，转 needs_human：task_id=%s msg=%s",
                    task.task_id,
                    exc.message,
                )
                await self._report_safe(
                    task,
                    state=_coerce_state(task.known_state),
                    detail=exc.message,
                    terminal=True,
                    terminal_status=TaskStatus.NEEDS_HUMAN,
                )
            except AppError as exc:
                logger.warning(
                    "执行失败：task_id=%s code=%s msg=%s",
                    task.task_id,
                    exc.err_code,
                    exc.message,
                )
                await self._report_safe(
                    task,
                    state=_coerce_state(task.known_state),
                    detail=exc.message,
                    terminal=True,
                    terminal_status=TaskStatus.FAILED,
                )

    async def execute(self, task: LeaseTask) -> None:
        """站点交互的实际调度：加购 → 校验 → 确认页 → 金额守卫 → 提交 → 付款

        每一步的顺序：动作 → 落证据 → 写本地 SQLite → 回报 gateway。
        站点交互当前未实现（site_interact 抛 NotImplementedError），第一步就会
        转到 _execute_with_renewal 的 except 分支上报 needs_human。
        """
        await self._db.ensure_started(task.task_id, task.site, task.intent)

        # 交易服务只覆盖乐天市场。其他站点直接转人工
        if task.site != "rakuten":
            raise NotImplementedError(f"site={task.site} 暂不在交易服务范围内（仅 rakuten）")

        # 步骤 1：加购
        await self._run_step(
            task, step_no=1, step_name="cart-add",
            action=lambda: self._site.add_to_cart(task),
            state=OrderState.IN_CART,
            detail="已加入购物车",
        )

        # 步骤 2：校验购物车
        await self._run_step(
            task, step_no=2, step_name="cart-check",
            action=lambda: self._site.verify_cart(task),
            state=OrderState.IN_CART,
            detail="购物车已校验",
        )

        # 步骤 3：进入下单确认页 + 金额守卫
        checkout_html = await self._site.enter_checkout(task)
        summary = await self._site.parse_checkout(checkout_html)
        self._enforce_amount_guard(task, summary.payable_yen)
        await self._run_step(
            task, step_no=3, step_name="order-confirm",
            action=self._noop(),
            state=OrderState.CREATED,
            detail=f"下单确认页已解析：应付 {summary.payable_yen} 円",
            evidence_meta={
                "payable_yen": summary.payable_yen,
                "site_order_id": summary.site_order_id,
                "pay_deadline": summary.pay_deadline,
            },
        )

        # 步骤 4：提交下单
        site_order_id = await self._site.submit_order(task)
        await self._run_step(
            task, step_no=4, step_name="order-submit",
            action=self._noop(),
            state=OrderState.ORDERED,
            site_order_id=site_order_id,
            detail=f"已提交下单，站点订单号 {site_order_id}",
        )

        # 步骤 5：付款
        await self._run_step(
            task, step_no=5, step_name="payment",
            action=lambda: self._site.pay(task, site_order_id),
            state=OrderState.AWAITING_PAYMENT,
            site_order_id=site_order_id,
            payable_yen=summary.payable_yen,
            pay_deadline=summary.pay_deadline,
            detail="已进入付款流程",
        )
        await self._report_safe(
            task,
            state=OrderState.PAID,
            site_order_id=site_order_id,
            payable_yen=summary.payable_yen,
            pay_deadline=summary.pay_deadline,
            detail="付款完成",
            terminal=True,
            terminal_status=TaskStatus.SUCCEEDED,
        )
        await self._db.mark_finished(task.task_id, OrderState.PAID.value)

        # 步骤 6：付款后监控（非阻塞，常驻轮询；当前未实现）
        try:
            await self._site.monitor(task, site_order_id)
        except NotImplementedError:
            logger.info("付款后监控未实现，跳过：task_id=%s", task.task_id)

    def _enforce_amount_guard(self, task: LeaseTask, payable_yen: int) -> None:
        """金额守卫：实际应付超过 intent.max_total_yen 或 RAKUTEN_ORDER_MAX_TOTAL_YEN 时拦截"""
        intent = task.intent or {}
        limit = intent.get("max_total_yen")
        if limit is None or limit <= 0:
            limit = self._settings.order_max_total_yen
        if limit > 0 and payable_yen > limit:
            raise OrderGuardError(
                f"实际应付 {payable_yen} 円超过上限 {limit} 円"
                f"（task_id={task.task_id}）"
            )

    @staticmethod
    def _noop() -> "callable":
        async def _f() -> None:
            return None

        return _f

    async def _run_step(
        self,
        task: LeaseTask,
        *,
        step_no: int,
        step_name: str,
        action: "callable",
        state: OrderState,
        detail: str,
        site_order_id: str | None = None,
        payable_yen: int | None = None,
        pay_deadline: str | None = None,
        evidence_meta: dict | None = None,
    ) -> None:
        """单步执行：动作 → 落证据 → 写本地 → 回报 gateway"""
        await action()
        meta = {
            "step": step_name,
            "state": state.value,
            **(evidence_meta or {}),
        }
        evidence_ref = self._evidence.write_step(
            task.task_id, step_no, step_name, meta=meta
        )
        await self._db.index_evidence(task.task_id, step_no, step_name, evidence_ref)
        await self._db.record_event(
            task.task_id, state.value, detail=detail, evidence_ref=evidence_ref
        )
        await self._gateway.report(
            task.task_id,
            self.worker_id,
            state=state,
            payable_yen=payable_yen,
            pay_deadline=pay_deadline,
            site_order_id=site_order_id,
            evidence_ref=evidence_ref,
            detail=detail,
        )

    async def _report_safe(
        self,
        task: LeaseTask,
        *,
        state: OrderState,
        detail: str,
        terminal: bool = False,
        terminal_status: TaskStatus | None = None,
        site_order_id: str | None = None,
        payable_yen: int | None = None,
        pay_deadline: str | None = None,
    ) -> None:
        """回报 gateway，失败只记日志不抛——主循环不能因为回报失败退出"""
        try:
            await self._gateway.report(
                task.task_id,
                self.worker_id,
                state=state,
                detail=detail,
                terminal=terminal,
                terminal_status=terminal_status,
                site_order_id=site_order_id,
                payable_yen=payable_yen,
                pay_deadline=pay_deadline,
            )
        except Exception:  # noqa: BLE001
            logger.exception("回报 gateway 失败：task_id=%s state=%s", task.task_id, state)

    @contextlib.asynccontextmanager
    async def _renew_lease_every(self, task: LeaseTask, *, interval: int):
        """后台任务：每隔 interval 秒续租一次。退出时停掉"""
        stop_event = asyncio.Event()

        async def _loop() -> None:
            while not stop_event.is_set():
                try:
                    await asyncio.wait_for(stop_event.wait(), timeout=interval)
                except asyncio.TimeoutError:
                    pass
                if stop_event.is_set():
                    return
                try:
                    await self._gateway.renew(task.task_id, self.worker_id)
                except AppError as exc:
                    logger.warning(
                        "续租失败：task_id=%s code=%s msg=%s",
                        task.task_id,
                        exc.err_code,
                        exc.message,
                    )
                    return
                except Exception:  # noqa: BLE001
                    logger.exception("续租异常：task_id=%s", task.task_id)
                    return

        renewal = asyncio.create_task(_loop(), name=f"renew-{task.task_id}")
        try:
            yield
        finally:
            stop_event.set()
            with contextlib.suppress(asyncio.CancelledError):
                await renewal