automatic_crawler/app/main.py

import asyncio
import json

from mq_http_sdk.mq_consumer import *
from mq_http_sdk.mq_exception import MQExceptionBase

sys.path.append(os.getcwd())

from application.common import AliyunLogger, get_consumer, ack_message
from application.config import TopicGroup


async def run(task_id, mode, platform):
    """
    传入参数，然后根据参数执行爬虫代码
    :param task_id: 任务id
    :param mode: 任务类型
    :param platform: 哪个抓取平台
    :return: None
    """
    # 创建一个aliyun日志对象
    logger = AliyunLogger(platform=platform, mode=mode)
    logger.logging(
        code=1003,
        message="{}: 开始一轮抓取".format(platform)
    )
    # 创建并一个子进程
    await asyncio.create_subprocess_shell(
        "python3 scheduler/run_spider_online.py --task_id {} --mode {} --platform {}".format(task_id, mode, platform)
    )


async def consume_single_message(spider):
    """
    消费单个消息，若消费成功则启动爬虫新协程；
    :param spider: 爬虫类
    """
    topic = spider['topic']
    group = spider['group']
    consumer = get_consumer(topic, group)
    try:
        messages = consumer.consume_message(wait_seconds=10, batch_size=1)
        if messages:
            # 在这里消费消息，做一些数据处理分析
            for single_message in messages:
                ack_message(mode=spider['mode'], platform=spider['platform'], recv_msgs=messages,
                            consumer=consumer)
                message_body = single_message.message_body
                task_id = json.loads(message_body)['id']
                print("成功消费消息，正在准备启动爬虫任务")
                print(message_body)
                # 创建爬虫task
                await asyncio.create_task(run(task_id, spider['mode'], spider['platform']))
                print("爬虫任务启动完成")
        else:
            message = "Messages Queue is Empty"
            print(message)

    except MQExceptionBase as err:
        # Topic中没有消息可消费。
        if err.type == "MessageNotExist":
            message = f"No new message! RequestId:{err.req_id}\n"
            print(message)
        else:
            message = f"Consume Message Fail! Exception:{err}\n"
            print(message)


async def main():
    """
    主函数
    """
    spider_list = TopicGroup().produce()
    while spider_list:
        async_tasks = []
        for spider in spider_list:
            task = asyncio.create_task(consume_single_message(spider))
            async_tasks.append(task)
        await asyncio.gather(*async_tasks)
        await asyncio.sleep(60)    # 每分钟接收一次MQ,


if __name__ == '__main__':
    # 运行主事件循环
    asyncio.run(main())