python - Scrapy:是否可以暂停 Scrapy 并在 x 分钟后恢复？

Question

我正在尝试抓取大型网站。他们有一个限速系统。 scrapy遇到403页面可以暂停10分钟吗？我知道我可以设置一个 DOWNLOAD_DELAY 但我注意到我可以通过设置一个小的 DOWNLOAD_DELAY 来更快地抓取，然后在它得到 403 时暂停 scrapy 几分钟。这样，速率限制大约每小时触发一次。

Answer 1

可以自己写重试中间件，放到middleware.py

from scrapy.downloadermiddlewares.retry import RetryMiddleware
from scrapy.utils.response import response_status_message
from time import sleep

class SleepRetryMiddleware(RetryMiddleware):
    def __init__(self, settings):
        RetryMiddleware.__init__(self, settings)

    def process_response(self, request, response, spider):
        if response.status in [403]:
            sleep(120)  # few minutes
            reason = response_status_message(response.status)
            return self._retry(request, reason, spider) or response

        return super(SleepRetryMiddleware, self).process_response(request, response, spider)

并且不要忘记更改 settings.py

DOWNLOADER_MIDDLEWARES = {
    'scrapy.downloadermiddlewares.retry.RetryMiddleware': None,
    'your_project.middlewares.SleepRetryMiddleware': 100,
}