五大核心组件、代理池

# -*- coding: utf-8 -*-

# Define here the models for your spider middleware
#
# See documentation in:
# https://docs.scrapy.org/en/latest/topics/spider-middleware.html
import random
from scrapy import signals

# class Midllepro1SpiderMiddleware(object):
#     # Not all methods need to be defined. If a method is not defined,
#     # scrapy acts as if the spider middleware does not modify the
#     # passed objects.
#
#     @classmethod
#     def from_crawler(cls, crawler):
#         # This method is used by Scrapy to create your spiders.
#         s = cls()
#         crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
#         return s
#
#     def process_spider_input(self, response, spider):
#         # Called for each response that goes through the spider
#         # middleware and into the spider.
#
#         # Should return None or raise an exception.
#         return None
#
#     def process_spider_output(self, response, result, spider):
#         # Called with the results returned from the Spider, after
#         # it has processed the response.
#
#         # Must return an iterable of Request, dict or Item objects.
#         for i in result:
#             yield i
#
#     def process_spider_exception(self, response, exception, spider):
#         # Called when a spider or process_spider_input() method
#         # (from other spider middleware) raises an exception.
#
#         # Should return either None or an iterable of Request, dict
#         # or Item objects.
#         pass
#
#     def process_start_requests(self, start_requests, spider):
#         # Called with the start requests of the spider, and works
#         # similarly to the process_spider_output() method, except
#         # that it doesn’t have a response associated.
#
#         # Must return only requests (not items).
#         for r in start_requests:
#             yield r
#
#     def spider_opened(self, spider):
#         spider.logger.info('Spider opened: %s' % spider.name)

# 定义UA池：
user_agent_list = [
    "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.1 "
    "(KHTML, like Gecko) Chrome/22.0.1207.1 Safari/537.1",
    "Mozilla/5.0 (X11; CrOS i686 2268.111.0) AppleWebKit/536.11 "
    "(KHTML, like Gecko) Chrome/20.0.1132.57 Safari/536.11",
    "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.6 "
    "(KHTML, like Gecko) Chrome/20.0.1092.0 Safari/536.6",
    "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.6 "
    "(KHTML, like Gecko) Chrome/20.0.1090.0 Safari/536.6",
    "Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/537.1 "
    "(KHTML, like Gecko) Chrome/19.77.34.5 Safari/537.1",
    "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/536.5 "
    "(KHTML, like Gecko) Chrome/19.0.1084.9 Safari/536.5",
    "Mozilla/5.0 (Windows NT 6.0) AppleWebKit/536.5 "
    "(KHTML, like Gecko) Chrome/19.0.1084.36 Safari/536.5",
    "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 "
    "(KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3",
    "Mozilla/5.0 (Windows NT 5.1) AppleWebKit/536.3 "
    "(KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3",
    "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_0) AppleWebKit/536.3 "
    "(KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3",
    "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 "
    "(KHTML, like Gecko) Chrome/19.0.1062.0 Safari/536.3",
    "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 "
    "(KHTML, like Gecko) Chrome/19.0.1062.0 Safari/536.3",
    "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 "
    "(KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3",
    "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 "
    "(KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3",
    "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/536.3 "
    "(KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3",
    "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 "
    "(KHTML, like Gecko) Chrome/19.0.1061.0 Safari/536.3",
    "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/535.24 "
    "(KHTML, like Gecko) Chrome/19.0.1055.1 Safari/535.24",
    "Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/535.24 "
    "(KHTML, like Gecko) Chrome/19.0.1055.1 Safari/535.24"
]


class Midllepro1DownloaderMiddleware(object):
    # 拦截正常请求：
    def process_request(self, request, spider):
        # 进行UA伪装：
        request.headers["User-Agent"] = random.choice(user_agent_list)
        # print(request.headers["User-Agent"])
        # # 挂高匿的免费代理ip：
        # request.meta["proxy"] = "http://39.137.95.74:80"
        # print(request.meta["proxy"])
        return None

    # 拦截所有的响应：
    def process_response(self, request, response, spider):
        return response

    # 拦截发生异常的请求对象：
    def process_exception(self, request, exception, spider):
        print(request)
        return request  # 将修正后的正常请求对象重新发送

    # def spider_opened(self, spider):
    #     spider.logger.info('Spider opened: %s' % spider.name)