方式一：在每个 Spider中设置（针对单个Spider）
class TencentSpider(scrapy.Spider):
name = ‘tencent‘
allowed_domains = [‘hr.tencent.com‘]
headers = {
‘User-Agent‘: ‘Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36‘,
}
def parse(self, response):
# 找到最后一页的页码
page_num = response.xpath(‘//div[@class="pagenav"]/a[last()-1]/text()‘).extract()[0]
# 生成每一页的请求
for i in range(1, int(page_num) + 1):
url = "https://hr.tencent.com/position.php?&start=%s#a" % (i * 10)
yield Request(url=url, headers=TencentSpider.headers, callback=self.parse)
方式二： 在中间件中设置（全局）
在配置文件中设置User-Agent集合
# 请求头
CUSTOM_USER_AGENT = [
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; AcooBrowser; .NET CLR 1.1.4322; .NET CLR 2.0.50727)",
"Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; Acoo Browser; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.0.04506)",
"Mozilla/4.0 (compatible; MSIE 7.0; AOL 9.5; AOLBuild 4337.35; Windows NT 5.1; .NET CLR 1.1.4322; .NET CLR 2.0.50727)",
"Mozilla/5.0 (Windows; U; MSIE 9.0; Windows NT 9.0; en-US)",
"Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Win64; x64; Trident/5.0; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET CLR 2.0.50727; Media Center PC 6.0)",
"Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET CLR 1.0.3705; .NET CLR 1.1.4322)",
"Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.2; .NET CLR 1.1.4322; .NET CLR 2.0.50727; InfoPath.2; .NET CLR 3.0.04506.30)",
"Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN) AppleWebKit/523.15 (KHTML, like Gecko, Safari/419.3) Arora/0.3 (Change: 287 c9dfb30)",
"Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/527+ (KHTML, like Gecko, Safari/419.3) Arora/0.6",
"Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.2pre) Gecko/20070215 K-Ninja/2.1.1",
"Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9) Gecko/20080705 Firefox/3.0 Kapiko/3.0",
"Mozilla/5.0 (X11; Linux i686; U;) Gecko/20070322 Kazehakase/0.4.5",
"Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.0.8) Gecko Fedora/1.9.0.8-1.fc10 Kazehakase/0.5.6",
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.11 (KHTML, like Gecko) Chrome/17.0.963.56 Safari/535.11",
"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_3) AppleWebKit/535.20 (KHTML, like Gecko) Chrome/19.0.1036.7 Safari/535.20",
"Opera/9.80 (Macintosh; Intel Mac OS X 10.6.8; U; fr) Presto/2.9.168 Version/11.52",
]
编写中间件逻辑
# 请求头添加随机user-agent
class RandomUserAgentMiddleware(object):
def __init__(self, agents):
self.agent = agents
@classmethod
def from_crawler(cls, crawler):
return cls(
agents=crawler.settings.get(‘CUSTOM_USER_AGENT‘)
)
def process_request(self, request, spider):
request.headers.setdefault(‘User-Agent‘, random.choice(self.agent))
激活中间件，并禁用默认的User-Agent中间件
DOWNLOADER_MIDDLEWARES = {
‘scrapy.downloadermiddleware.useragent.UserAgentMiddleware‘: None,
‘day1.middlewares.RandomUserAgentMiddleware‘: 10,
}
查看请求头信息
响应 response 中封装了请求对应request，因此可以根据request中查看该响应请求时的请求头信息。
def parse(self, response):
print(response.request)
print(response.request.headers[‘User-Agent‘])
使用 fake-useragent 模块随机生成 User-Agent
上面的user-agent是在配置文件中预先设定好的，我们也可以使用python模块 fake-useragent 生成user-agent
安装：
pip install fake-useragent
简单使用：
from fake_useragent import UserAgent ua = UserAgent() #ie浏览器的user agent print(ua.ie) Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; chromeframe/13.0.782.215) #opera浏览器 print(ua.opera) #chrome浏览器 print(ua.chrome) #firefox浏览器 print(ua.firefox) #safri浏览器 print(ua.safari) #最常用的方式 #写爬虫最实用的是可以随意变换headers，一定要有随机性。支持随机生成请求头 print(ua.random)
在中间件中使用
import random
from scrapy import signals
from fake_useragent import UserAgent
class RandomUserAgentMiddleware(object):
def __init__(self):
self.agent = UserAgent()
@classmethod
def from_crawler(cls, crawler):
return cls()
def process_request(self, request, spider):
request.headers.setdefault(‘User-Agent‘, self.agent.random)
原文地址：https://www.cnblogs.com/yuqiangli0616/p/9277263.html
时间： 2024-07-30 15:57:57