How to use python to crawl CSDN popular comment URLs and store them in redis
May 28, 2023 pm 03:17 PM1. Configure webdriver
Download the Google Chrome driver, and configure it
import timeimport randomfrom PIL import Imagefrom selenium import webdriverfrom selenium.webdriver.common.by import Byfrom selenium.webdriver.support.ui import WebDriverWaitfrom selenium.webdriver.support import expected_conditions as ECif __name__ == '__main__':options = webdriver.ChromeOptions()options.binary_location = r'C:UsershhhAppDataLocalGoogleChromeApplication谷歌瀏覽器.exe'# driver=webdriver.Chrome(executable_path=r'D:360Chromechromedriverchromedriver.exe')driver = webdriver.Chrome(options=options)#以java模塊為例driver.get('https://www.csdn.net/nav/java')for i in range(1,20):driver.execute_script("window.scrollTo(0, document.body.scrollHeight)")time.sleep(2)
2. Get the URL
from bs4 import BeautifulSoupfrom lxml import etree html = etree.HTML(driver.page_source)# soup = BeautifulSoup(html, 'lxml')# soup_herf=soup.find_all("#feedlist_id > li:nth-child(1) > div > div > h2 > a")# soup_herftitle = html.xpath('//*[@id="feedlist_id"]/li/div/div/h2/a/@href')
You can see, Crawled a lot at once,The speed is very fast
3. Write to Redis
After importing the redis package,Configure the redis port and redis database& #xff0c;Use rpush function to write
Open redis
import redis r_link = redis.Redis(port='6379', host='localhost', decode_responses=True, db=1)for u in title:print("準備寫入{}".format(u))r_link.rpush("csdn_url", u)print("{}寫入成功!".format(u))print('=' * 30, 'n', "共計寫入url:{}個".format(len(title)), 'n', '=' * 30)
Done!
You can see it in Redis Desktop Manager Crawling and writing are very fast.
To use it, just use rpop to pop it off the stack
one_url = r_link.rpop("csdn_url)")while one_url:print("{}被彈出!".format(one_url))
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