Building web crawlers using Python and Redis: How to deal with anti-crawler strategies
Introduction:
In recent years, with the rapid development of the Internet, web crawlers have become one of the important means of obtaining information and data. . However, in order to protect their own data, many websites adopt various anti-crawler strategies, which causes problems for crawlers. This article will introduce how to use Python and Redis to build a powerful web crawler and solve common anti-crawler strategies.
import requests from bs4 import BeautifulSoup import redis # 设置爬虫的基本参数 base_url = "https://example.com" # 待爬取的网站 user_agent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.82 Safari/537.36" # 设置User-Agent # 初始化Redis连接 redis_host = "localhost" # Redis主机地址 redis_port = 6379 # Redis端口号 r = redis.StrictRedis(host=redis_host, port=redis_port, db=0)
headers = { "User-Agent": user_agent }
# 从Redis中获取代理IP proxy_ip = r.srandmember("proxy_ip_pool") proxies = { "http": "http://" + proxy_ip, "https": "https://" + proxy_ip }
# 处理验证码,此处以Pillow库为例 from PIL import Image import pytesseract # 下载验证码图片 captcha_url = base_url + "/captcha.jpg" response = requests.get(captcha_url, headers=headers, proxies=proxies) # 保存验证码图片 with open("captcha.jpg", "wb") as f: f.write(response.content) # 识别验证码 captcha_image = Image.open("captcha.jpg") captcha_text = pytesseract.image_to_string(captcha_image)
from selenium import webdriver # 使用Selenium模拟浏览器访问 driver = webdriver.Chrome() driver.get(base_url) # 等待页面加载完成 time.sleep(3) # 获取页面源码 page_source = driver.page_source # 使用BeautifulSoup解析页面 soup = BeautifulSoup(page_source, "html.parser")
# 填写登录表单 driver.find_element_by_id("username").send_keys("your_username") driver.find_element_by_id("password").send_keys("your_password") # 提交表单 driver.find_element_by_id("submit").click()
Conclusion:
By using Python and Redis to build a web crawler, we can effectively deal with common anti-crawler strategies and achieve more stable and efficient data acquisition. In practical applications, further optimization and adaptation are required based on the anti-crawler strategy of the specific website. I hope this article can be helpful to your crawler development work.
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