FrameTour-RenderWorker/services/task_executor.py

# -*- coding: utf-8 -*-
"""
任务执行器

管理任务的并发执行，协调处理器、租约服务等组件。
"""

import logging
import threading
from concurrent.futures import ThreadPoolExecutor, Future
from typing import Dict, Optional, TYPE_CHECKING

from domain.task import Task, TaskType
from domain.result import TaskResult, ErrorCode
from domain.config import WorkerConfig
from core.handler import TaskHandler
from services.lease_service import LeaseService

if TYPE_CHECKING:
    from services.api_client import APIClientV2

logger = logging.getLogger(__name__)


class TaskExecutor:
    """
    任务执行器

    负责任务的并发调度和执行，包括：
    - 注册和管理任务处理器
    - 维护任务执行状态
    - 协调租约续期
    - 上报执行结果
    """

    def __init__(self, config: WorkerConfig, api_client: 'APIClientV2'):
        """
        初始化任务执行器

        Args:
            config: Worker 配置
            api_client: API 客户端
        """
        self.config = config
        self.api_client = api_client

        # 任务处理器注册表
        self.handlers: Dict[TaskType, TaskHandler] = {}

        # 当前任务跟踪
        self.current_tasks: Dict[str, Task] = {}
        self.current_futures: Dict[str, Future] = {}

        # 线程池
        self.executor = ThreadPoolExecutor(
            max_workers=config.max_concurrency,
            thread_name_prefix="TaskWorker"
        )

        # 线程安全锁
        self.lock = threading.Lock()

        # 注册处理器
        self._register_handlers()

    def _register_handlers(self):
        """注册所有任务处理器"""
        # 延迟导入以避免循环依赖
        from handlers.render_video import RenderSegmentVideoHandler
        from handlers.prepare_audio import PrepareJobAudioHandler
        from handlers.package_ts import PackageSegmentTsHandler
        from handlers.finalize_mp4 import FinalizeMp4Handler

        handlers = [
            RenderSegmentVideoHandler(self.config, self.api_client),
            PrepareJobAudioHandler(self.config, self.api_client),
            PackageSegmentTsHandler(self.config, self.api_client),
            FinalizeMp4Handler(self.config, self.api_client),
        ]

        for handler in handlers:
            task_type = handler.get_supported_type()
            self.handlers[task_type] = handler
            logger.debug(f"Registered handler for {task_type.value}")

    def get_current_task_ids(self) -> list:
        """
        获取当前正在执行的任务 ID 列表

        Returns:
            任务 ID 列表
        """
        with self.lock:
            return list(self.current_tasks.keys())

    def get_current_task_count(self) -> int:
        """
        获取当前正在执行的任务数量

        Returns:
            任务数量
        """
        with self.lock:
            return len(self.current_tasks)

    def can_accept_task(self) -> bool:
        """
        检查是否可以接受新任务

        Returns:
            是否可以接受
        """
        return self.get_current_task_count() < self.config.max_concurrency

    def submit_task(self, task: Task) -> bool:
        """
        提交任务到线程池

        Args:
            task: 任务实体

        Returns:
            是否提交成功
        """
        with self.lock:
            # 检查任务是否已在执行
            if task.task_id in self.current_tasks:
                logger.warning(f"[task:{task.task_id}] Task already running, skipping")
                return False

            # 检查是否有对应的处理器
            if task.task_type not in self.handlers:
                logger.error(f"[task:{task.task_id}] No handler for type: {task.task_type.value}")
                return False

            # 记录任务
            self.current_tasks[task.task_id] = task

            # 提交到线程池
            future = self.executor.submit(self._process_task, task)
            self.current_futures[task.task_id] = future

            logger.info(f"[task:{task.task_id}] Submitted ({task.task_type.value})")
            return True

    def _process_task(self, task: Task):
        """
        处理单个任务（在线程池中执行）

        Args:
            task: 任务实体
        """
        task_id = task.task_id
        logger.info(f"[task:{task_id}] Starting {task.task_type.value}")

        # 启动租约续期服务
        lease_service = LeaseService(
            self.api_client,
            task_id,
            interval=self.config.lease_extension_threshold,
            extension=self.config.lease_extension_duration
        )
        lease_service.start()

        try:
            # 报告任务开始
            self.api_client.report_start(task_id)

            # 获取处理器
            handler = self.handlers.get(task.task_type)
            if not handler:
                raise ValueError(f"No handler for task type: {task.task_type}")

            # 执行前钩子
            handler.before_handle(task)

            # 执行任务
            result = handler.handle(task)

            # 执行后钩子
            handler.after_handle(task, result)

            # 上报结果
            if result.success:
                self.api_client.report_success(task_id, result.data)
                logger.info(f"[task:{task_id}] Completed successfully")
            else:
                error_code = result.error_code.value if result.error_code else 'E_UNKNOWN'
                self.api_client.report_fail(task_id, error_code, result.error_message or '')
                logger.error(f"[task:{task_id}] Failed: {result.error_message}")

        except Exception as e:
            logger.error(f"[task:{task_id}] Exception: {e}", exc_info=True)
            self.api_client.report_fail(task_id, 'E_UNKNOWN', str(e))

        finally:
            # 停止租约续期
            lease_service.stop()

            # 从当前任务中移除
            with self.lock:
                self.current_tasks.pop(task_id, None)
                self.current_futures.pop(task_id, None)

    def shutdown(self, wait: bool = True):
        """
        关闭执行器

        Args:
            wait: 是否等待所有任务完成
        """
        logger.info("Shutting down task executor...")

        # 关闭线程池
        self.executor.shutdown(wait=wait)

        # 清理状态
        with self.lock:
            self.current_tasks.clear()
            self.current_futures.clear()

        logger.info("Task executor shutdown complete")

    def get_handler(self, task_type: TaskType) -> Optional[TaskHandler]:
        """
        获取指定类型的处理器

        Args:
            task_type: 任务类型

        Returns:
            处理器实例，不存在则返回 None
        """
        return self.handlers.get(task_type)