UA池和代理池（IP)

UA池(每一次请求采用池中的随机UA)

a) 在中间件类中进行导包

from scrapy.contrib.downloadermiddleware.useragent import UserAgentMiddleware 

b)封装一个基于UserAgentMiddleware的类，且重写该类

　　例：

　　middleware.py

from scrapy.contrib.downloadermiddleware.useragent import UserAgentMiddleware
import random

ua_list = ['Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_6_8; en-us) AppleWebKit/534.50 (KHTML, like Gecko) Version/5.1 Safari/534.50',
           'User-Agent:Mozilla/5.0 (Windows; U; Windows NT 6.1; en-us) AppleWebKit/534.50 (KHTML, like Gecko) Version/5.1 Safari/534.50',
           'User-Agent:Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0;',
           'User-Agent:Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0)',
           'User-Agent:Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0)',
           'User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)',
           'User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:2.0.1) Gecko/20100101 Firefox/4.0.1',
           'User-Agent:Mozilla/5.0 (Windows NT 6.1; rv:2.0.1) Gecko/20100101 Firefox/4.0.1',
           'User-Agent:Opera/9.80 (Macintosh; Intel Mac OS X 10.6.8; U; en) Presto/2.8.131 Version/11.11']
ip_http_list = ['90.229.216.218:46796', '110.235.250.7:49341', '81.163.62.136:41258', '195.34.207.47:60878']
ip_https_list = ['140.227.207.211:60088', '140.227.209.210:60088', '185.132.133.102:1080']


class UserAgentRandom(UserAgentMiddleware):
    def process_request(self, request, spider):
        ua = random.choice(ua_list)
        request.headers.setdefault('User-Agent', ua)

settings.py

DOWNLOADER_MIDDLEWARES = {
   'handle5.middlewares.Handle5DownloaderMiddleware': 543,
   'handle5.middlewares.UserAgentRandom': 542,
   'handle5.middlewares.IpRandom': 541
}

代理池（IP 每次请求的IP地址随机从IP池中获取）

middleware.py

class IpRandom:
    def process_request(self, request, spider):
        url = request.url
        head = url.split(":")[0]
        if head == "http":
            request.meta["proxy"] = "http://" + random.choice(ip_http_list)
        else:
            request.meta["proxy"] = "https://" + random.choice(ip_https_list)