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目录
一、为什么要搭建爬虫代理池
在众多的网站防爬措施中，有一种是根据ip的访问频率进行限制，即在某一时间段内，当某个ip的访问次数达到一定的阀值时，该ip就会被拉黑、在一段时间内禁止访问。
应对的方法有两种：
1. 降低爬虫的爬取频率，避免IP被限制访问，缺点显而易见：会大大降低爬取的效率。
2. 搭建一个IP代理池，使用不同的IP轮流进行爬取。
二、搭建思路
1、从代理网站(如：西刺代理、快代理、云代理、无忧代理)爬取代理IP；
2、验证代理IP的可用性（使用代理IP去请求指定URL，根据响应验证代理IP是否生效）；
3、将可用的代理IP保存到数据库；
在《Python爬虫代理池搭建》一文中我们已经使用Python的 requests 模块简单实现了一个IP代理池搭建，但是爬取速度较慢。由于西刺代理、快代理和云代理等网站需要爬取的IP代理列表页多达上千页，使用此种方法来爬取其实并不适合。
本文将以快代理网站的IP代理爬取为例，示例如何使用 Scrapy-Redis 来爬取代理IP。
三、搭建代理池
scrapy 项目的目录结构如下：
![基于Scrapy的IP代理池搭建[通俗易懂]](https://img-blog.csdnimg.cn/20190520172050348.png)
![基于Scrapy的IP代理池搭建[通俗易懂]](https://javaforall.net/wp-content/uploads/2020/11/2020110817443450.jpg)
items.py
# -*- coding: utf-8 -*-
import re
import scrapy
from proxy_pool.settings import PROXY_URL_FORMATTER
schema_pattern = re.compile(r'http|https$', re.I)
ip_pattern = re.compile(r'^([0-9]{1,3}.){3}[0-9]{1,3}$', re.I)
port_pattern = re.compile(r'^[0-9]{2,5}$', re.I)
class ProxyPoolItem(scrapy.Item):
# define the fields for your item here like:
# name = scrapy.Field()
'''
{
"schema": "http", # 代理的类型
"ip": "127.0.0.1", # 代理的IP地址
"port": "8050", # 代理的端口号
"original":"西刺代理",
"used_total": 11, # 代理的使用次数
"success_times": 5, # 代理请求成功的次数
"continuous_failed": 3, # 使用代理发送请求，连续失败的次数
"created_time": "2018-05-02" # 代理的爬取时间
}
'''
schema = scrapy.Field()
ip = scrapy.Field()
port = scrapy.Field()
original = scrapy.Field()
used_total = scrapy.Field()
success_times = scrapy.Field()
continuous_failed = scrapy.Field()
created_time = scrapy.Field()
# 检查IP代理的格式是否正确
def _check_format(self):
if self['schema'] is not None and self['ip'] is not None and self['port'] is not None:
if schema_pattern.match(self['schema']) and ip_pattern.match(self['ip']) and port_pattern.match(
self['port']):
return True
return False
# 获取IP代理的url
def _get_url(self):
return PROXY_URL_FORMATTER % {'schema': self['schema'], 'ip': self['ip'], 'port': self['port']}kuai_proxy.py
# -*- coding: utf-8 -*-
import re
import time
import scrapy
from proxy_pool.utils import strip, logger
from proxy_pool.items import ProxyPoolItem
class KuaiProxySpider(scrapy.Spider):
name = 'kuai_proxy'
allowed_domains = ['kuaidaili.com']
start_urls = ['https://www.kuaidaili.com/free/inha/1/', 'https://www.kuaidaili.com/free/intr/1/']
def parse(self, response):
logger.info('正在爬取：< ' + response.request.url + ' >')
tr_list = response.css("div#list>table>tbody tr")
for tr in tr_list:
ip = tr.css("td[data-title='IP']::text").get()
port = tr.css("td[data-title='PORT']::text").get()
schema = tr.css("td[data-title='类型']::text").get()
if schema.lower() == "http" or schema.lower() == "https":
item = ProxyPoolItem()
item['schema'] = strip(schema).lower()
item['ip'] = strip(ip)
item['port'] = strip(port)
item['original'] = '快代理'
item['created_time'] = time.strftime('%Y-%m-%d', time.localtime(time.time()))
if item._check_format():
yield item
next_page = response.xpath("//a[@class='active']/../following-sibling::li/a/@href").get()
if next_page is not None:
next_url = 'https://www.kuaidaili.com' + next_page
yield scrapy.Request(next_url)middlewares.py
# -*- coding: utf-8 -*-
import random
from proxy_pool.utils import logger
# 随机选择 IP 代理下载器中间件
class RandomProxyMiddleware(object):
# 从 settings 的 PROXIES 列表中随机选择一个作为代理
def process_request(self, request, spider):
proxy = random.choice(spider.settings['PROXIES'])
request.meta['proxy'] = proxy
return None
# 随机选择 User-Agent 的下载器中间件
class RandomUserAgentMiddleware(object):
def process_request(self, request, spider):
# 从 settings 的 USER_AGENTS 列表中随机选择一个作为 User-Agent
user_agent = random.choice(spider.settings['USER_AGENT_LIST'])
request.headers['User-Agent'] = user_agent
return None
def process_response(self, request, response, spider):
# 验证 User-Agent 设置是否生效
logger.info("headers ::> User-Agent = " + str(request.headers['User-Agent'], encoding="utf8"))
return responsepipelines.py
# -*- coding: utf-8 -*-
import json
import redis
from proxy_pool.settings import REDIS_HOST,REDIS_PORT,REDIS_PARAMS,PROXIES_UNCHECKED_LIST,PROXIES_UNCHECKED_SET
server = redis.StrictRedis(host=REDIS_HOST, port=REDIS_PORT,password=REDIS_PARAMS['password'])
class ProxyPoolPipeline(object):
# 将可用的IP代理添加到代理池队列
def process_item(self, item, spider):
if not self._is_existed(item):
server.rpush(PROXIES_UNCHECKED_LIST, json.dumps(dict(item),ensure_ascii=False))
# 检查IP代理是否已经存在
def _is_existed(self,item):
added = server.sadd(PROXIES_UNCHECKED_SET, item._get_url())
return added == 0settings.py
# -*- coding: utf-8 -*-
BOT_NAME = 'proxy_pool'
SPIDER_MODULES = ['proxy_pool.spiders']
NEWSPIDER_MODULE = 'proxy_pool.spiders'
# 保存未检验代理的Redis key
PROXIES_UNCHECKED_LIST = 'proxies:unchecked:list'
# 已经存在的未检验HTTP代理和HTTPS代理集合
PROXIES_UNCHECKED_SET = 'proxies:unchecked:set'
# 代理地址的格式化字符串
PROXY_URL_FORMATTER = '%(schema)s://%(ip)s:%(port)s'
# 通用请求头字段
DEFAULT_REQUEST_HEADERS = {
'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8',
'Accept-Encoding': 'gzip, deflate, br',
'Accept-Language': 'zh-CN,zh;q=0.9,en;q=0.8,zh-TW;q=0.7',
'Connection': 'keep-alive'
}
# 请求太频繁会导致 503 ,在此设置 5 秒请求一次
DOWNLOAD_DELAY = 5 # 250 ms of delay
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"
]
# Obey robots.txt rules
ROBOTSTXT_OBEY = False
# Enable or disable downloader middlewares
# See https://doc.scrapy.org/en/latest/topics/downloader-middleware.html
DOWNLOADER_MIDDLEWARES = {
'proxy_pool.middlewares.RandomUserAgentMiddleware': 543,
# 'proxy_pool.middlewares.RandomProxyMiddleware': 544,
}
ITEM_PIPELINES = {
'proxy_pool.pipelines.ProxyPoolPipeline': 300,
}
PROXIES = [
"https://171.13.92.212:9797",
"https://164.163.234.210:8080",
"https://143.202.73.219:8080",
"https://103.75.166.15:8080"
]
######################################################
##############下面是Scrapy-Redis相关配置################
######################################################
# 指定Redis的主机名和端口
REDIS_HOST = '172.16.250.238'
REDIS_PORT = 6379
REDIS_PARAMS = {'password': '123456'}
# 调度器启用Redis存储Requests队列
SCHEDULER = "scrapy_redis.scheduler.Scheduler"
# 确保所有的爬虫实例使用Redis进行重复过滤
DUPEFILTER_CLASS = "scrapy_redis.dupefilter.RFPDupeFilter"
# 将Requests队列持久化到Redis，可支持暂停或重启爬虫
SCHEDULER_PERSIST = True
# Requests的调度策略，默认优先级队列
SCHEDULER_QUEUE_CLASS = 'scrapy_redis.queue.PriorityQueue'utils.py
# -*- coding: utf-8 -*-
import logging
# 设置日志输出格式
logging.basicConfig(level=logging.INFO,
format='[%(asctime)-15s] [%(levelname)8s] [%(name)10s ] - %(message)s (%(filename)s:%(lineno)s)',
datefmt='%Y-%m-%d %T'
)
logger = logging.getLogger(__name__)
# Truncate header and tailer blanks
def strip(data):
if data is not None:
return data.strip()
return data
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