NeteaseUrl/services/tasks.py

# -*- coding: utf-8 -*-
"""任务监控循环与设备心跳。

（自 services/runtime.py 拆出，行为与原实现一致。）
"""

import os
import shutil
import time
import traceback

import auth_system
from core.config import (
    CANCEL_AFTER_SECONDS,
    HEARTBEAT_INTERVAL,
    PAUSE_AFTER_SECONDS,
    RESULT_RETENTION_SECONDS,
)
from core.state import (
    DEVICE_LAST_SEEN,
    DEVICE_LAST_SEEN_LOCK,
    DOWNLOAD_TASKS,
    DOWNLOAD_TASKS_LOCK,
)

from ._shared import (
    _LEDGER_LAST_CLEANUP,
    _LEDGER_LAST_RECOVER,
    _MONITOR_ERR_TS,
    _TASKS_SWEEP_LAST,
    _sweep_rate_buckets,
)
from ._taskcore import (
    _task_files,
)
from .api_service import (
    api_service,
)


def _quiesce_tasks_for_restore() -> None:
    """恢复数据库前取消全部在途任务（worker 不再引用旧库用户结算）"""
    with DOWNLOAD_TASKS_LOCK:
        for task in DOWNLOAD_TASKS.values():
            if task.get('status') in ('queued', 'running', 'paused'):
                task['status'] = 'canceled'
                task['msg'] = '数据库恢复中，任务已取消（费用按实际交付结算）'
                task['completed_at'] = time.time()
                try:
                    task['cancel'].set()
                except Exception:
                    pass


# 数据库恢复前静默在途任务
auth_system.register_before_restore_hook(_quiesce_tasks_for_restore)


def _sweep_download_cache(max_age_seconds: int = RESULT_RETENTION_SECONDS) -> None:
    """下载缓存清扫（配套：批量任务不再即时删除共享缓存，改由这里按年龄回收）。
    只清扫 downloads 根目录的普通文件，不碰 tasks/ 子目录（那是任务专属交付物）。"""
    try:
        root = api_service.downloads_path
        now = time.time()
        for p in root.iterdir():
            try:
                if p.is_file() and now - p.stat().st_mtime > max_age_seconds:
                    p.unlink()
            except OSError:
                pass
    except Exception:
        pass


def _task_monitor_loop() -> None:
    """后台监控：
    - 心跳超时（40s）→ 暂停离线设备的批量任务，释放排队名额给下一位
    - 心跳超时 > 30 分钟 → 自动取消该设备的所有未完成任务并清理文件
    - 终态任务按 completed_at 保留 35 分钟（与前端「领取」入口对齐）
    - 运行中/排队/暂停任务超过 4 小时仍未结束 → 置取消（cancel Event 一并置位）
    - 下载缓存按年龄清扫（配套，同为 35 分钟口径）
    - 顺带清理限流桶中的过期项（不再只依赖"新建桶时"的清理时机）
    """
    while True:
        time.sleep(HEARTBEAT_INTERVAL)
        try:
            now = time.time()
            # 终态任务清理（按完成时刻；删除失败保留记录下轮重试，最多 8 次）----
            # 锁内只收集过期清单，文件删除移到锁外——GB 级任务目录
            # 的删除曾阻塞锁数十秒，期间全站进度上报/提交/取消/领取全部停摆
            finished_done: list[str] = []
            finished_retry: list[str] = []
            expired: list[tuple] = []
            with DOWNLOAD_TASKS_LOCK:
                for tid, task in DOWNLOAD_TASKS.items():
                    if task.get('status') not in ('done', 'error', 'canceled'):
                        continue
                    done_at = task.get('completed_at') or 0
                    # 兼容无 completed_at 的旧记录：回退到 start
                    if not done_at:
                        done_at = task.get('start', 0)
                    if now - done_at <= RESULT_RETENTION_SECONDS:
                        continue
                    expired.append((tid, _task_files(task),
                                    api_service.downloads_path / 'tasks' / tid))
            cleanup_results: list[tuple] = []
            for tid, files, task_dir in expired:
                all_removed = True
                for f in files:
                    try:
                        os.remove(f)
                    except FileNotFoundError:
                        pass
                    except OSError:
                        all_removed = False   # 文件暂时不可删（被占用等）
                if task_dir.exists():
                    shutil.rmtree(str(task_dir), ignore_errors=True)
                    if task_dir.exists():
                        all_removed = False
                cleanup_results.append((tid, all_removed))
            with DOWNLOAD_TASKS_LOCK:
                for tid, all_removed in cleanup_results:
                    task = DOWNLOAD_TASKS.get(tid)
                    if task is None:
                        finished_done.append(tid)   # 锁外期间已被其他路径移除
                        continue
                    if all_removed:
                        finished_done.append(tid)
                    else:
                        task['_cleanup_tries'] = int(task.get('_cleanup_tries') or 0) + 1
                        if task['_cleanup_tries'] >= 8:
                            # 重试多次仍失败：放弃记录但大声记录日志（文件留给缓存清扫兜底）
                            api_service.logger.warning(
                                f"任务 {tid} 结果文件多次清理失败，已放弃（文件可能被占用）")
                            finished_done.append(tid)
                        else:
                            finished_retry.append(tid)
                for tid in finished_done:
                    DOWNLOAD_TASKS.pop(tid, None)
            if finished_done:
                api_service.logger.info(f"监控线程清理过期终态任务: {finished_done}")
            if finished_retry:
                api_service.logger.info(f"监控线程保留清理失败任务待重试: {finished_retry}")
            # ---- 长时间未结束的任务：置取消（含 cancel Event，唤醒可能的阻塞等待）----
            timeout_settle: list[str] = []
            with DOWNLOAD_TASKS_LOCK:
                for tid, task in DOWNLOAD_TASKS.items():
                    if (task.get('status') in ('queued', 'running', 'paused')
                            and now - task.get('start', 0) > 4 * 3600):
                        task['status'] = 'canceled'
                        task['msg'] = '任务超时未完成，已自动取消（费用按实际交付结算）'
                        task['completed_at'] = time.time()
                        try:
                            task['cancel'].set()
                        except Exception:
                            pass
                        # worker 线程已死则无人再走终态结算——监控代为按账本
                        # 结算退款（settle 幂等：worker 若已结算过，此处返回 0）
                        th = task.get('worker_thread')
                        if th is not None and not th.is_alive():
                            timeout_settle.append(tid)
                        api_service.logger.warning(f"任务超时自动取消: {tid}")
            # 结算移到任务锁外（同 _mark_task_terminal 口径）——
            # 库忙 15s 不再随任务锁波及全站任务端点
            for tid in timeout_settle:
                try:
                    auth_system.ledger_settle(tid, 0, 'timeout')
                except Exception:
                    pass
            # ---- 下载缓存清扫（保留期同交付口径 35 分钟）+ 限流桶过期项顺手清理 ----
            _sweep_download_cache(RESULT_RETENTION_SECONDS)
            _sweep_rate_buckets()
            # 账本周期兜底（原仅启动执行一次）----
            # 孤儿对账：长运行进程内 open 且账龄 > 5h（严格大于任务 4h 硬超时 + 监控
            # tick 抖动——账本行 created_at 整秒截断使账龄恒 ≥ 任务龄，旧 4h 相等口径
            # 存在抢退合法 4h+ 长任务的窗口）的行每分钟周期检查退回；
            # settled 行 90 天清理改为每小时低频执行，防长运行进程下表无界增长
            try:
                # 时间戳门槛替代 tick 取模——单轮工作段超过周期时
                # 取模落点会被整段跳过，时间戳门槛只延迟不漏跑
                if now - _LEDGER_LAST_RECOVER['ts'] > 60:
                    _LEDGER_LAST_RECOVER['ts'] = now
                    auth_system.ledger_recover_orphans(max_age_seconds=5 * 3600)
                if now - _LEDGER_LAST_CLEANUP['ts'] > 24 * 3600:
                    _LEDGER_LAST_CLEANUP['ts'] = now
                    auth_system.ledger_cleanup_settled(90 * 86400)
            except Exception as e:
                api_service.logger.warning(f"账本周期兜底异常（下轮重试）: {e}")
            # tasks/ 孤儿目录每小时低频补扫（>24h 且无记录）----
            try:
                if now - _TASKS_SWEEP_LAST['ts'] > 3600:
                    _TASKS_SWEEP_LAST['ts'] = now
                    tasks_root = api_service.downloads_path / 'tasks'
                    if tasks_root.exists():
                        for d in tasks_root.iterdir():
                            try:
                                if (d.is_dir() and d.name not in DOWNLOAD_TASKS
                                        and now - d.stat().st_mtime > 24 * 3600):
                                    shutil.rmtree(str(d), ignore_errors=True)
                                    api_service.logger.info(f"tasks 孤儿目录补扫移除: {d.name}")
                            except FileNotFoundError:
                                pass   # 单条竞态不中止整轮扫描
                            except OSError:
                                pass
            except Exception as e:
                api_service.logger.warning(f"tasks 孤儿目录补扫异常（下轮重试）: {e}")
            # ---- 设备心跳离线处理 ----
            with DEVICE_LAST_SEEN_LOCK:
                offline = {d: now - ts for d, ts in DEVICE_LAST_SEEN.items() if now - ts > PAUSE_AFTER_SECONDS}
            if not offline:
                continue
            with DOWNLOAD_TASKS_LOCK:
                for tid, task in DOWNLOAD_TASKS.items():
                    dev = task.get('device_id')
                    gap = offline.get(dev) if dev else None
                    if not gap:
                        continue
                    st = task.get('status')
                    if gap > CANCEL_AFTER_SECONDS and st in ('queued', 'running', 'paused'):
                        # 离线超 30 分钟：请求取消（文件删除与退款统一交给 worker 的
                        # 取消收尾/终态清理；worker 已不在时由启动对账按账本兜底）
                        task['status'] = 'canceled'
                        task['msg'] = '设备离线超过 30 分钟，任务已自动取消'
                        task['completed_at'] = time.time()
                        try:
                            task['cancel'].set()
                        except Exception:
                            pass
                        api_service.logger.info(f"设备离线超 30 分钟自动请求取消: {tid}")
                    elif task.get('type') == 'batch' and st in ('queued', 'running'):
                        # 心跳超时：先暂停，让出排队名额给下一位
                        task['status'] = 'paused'
                        task['msg'] = '设备离线，任务暂停（重新打开页面自动恢复）'
                        task['pause'].set()
        except Exception:
            # 持续异常不能完全静默（否则监控失能无人知晓）：限频记录，每 10 分钟最多一条
            _now = time.time()
            _MONITOR_ERR_TS['n'] += 1
            if _now - _MONITOR_ERR_TS['ts'] > 600:
                api_service.logger.warning(
                    f"任务监控循环异常（近 10 分钟累计 {_MONITOR_ERR_TS['n']} 次，"
                    f"最后异常见堆栈）: {traceback.format_exc()[-600:]}")
                _MONITOR_ERR_TS['ts'] = _now
                _MONITOR_ERR_TS['n'] = 0


def _touch_device(device_id: str) -> None:
    """记录设备心跳时间（设备表容量上限——device_id 是客户端任意串，
    登录用户可提交海量随机 ID 使字典无界增长，超限清最旧；
    入口已统一钳 64，此处兜底再钳一次防新调用点绕过）"""
    device_id = str(device_id or '')[:64]
    if not device_id:
        return
    with DEVICE_LAST_SEEN_LOCK:
        if len(DEVICE_LAST_SEEN) >= 5000:
            # 保留最近心跳的设备：按最后心跳时间排序，砍掉最旧的一半
            for d in sorted(DEVICE_LAST_SEEN, key=lambda k: DEVICE_LAST_SEEN.get(k, 0.0))[:2500]:
                DEVICE_LAST_SEEN.pop(d, None)
        DEVICE_LAST_SEEN[device_id] = time.time()