知乎推荐文章页面的爬取是比较复杂的，应为其涉及大量ajax/js解析和知乎的验证码登录，这给爬虫爬取造成了好多麻烦，不过有一款非常强大的工具可以轻松解决这些问题——selenium，它是一款测试工具，不过他也提供了许多爬虫用途，通过它与chrome配合使用，可以模拟浏览器进行登录，同时获取到js渲染后的网站源代码，非常方便。什么都不说了，上代码：
#知乎推荐文章爬取
#2017/8/6
# -*- encoding = utf-8 -*-
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
from selenium.common.exceptions import TimeoutException
from selenium.common.exceptions import NoSuchElementException
from bs4 import BeautifulSoup
import csv
import os
import time
import re
driver = webdriver.Chrome()
#登录知乎
def putcookies(account,password):
try:
driver.get('https://www.zhihu.com/#signin')
WebDriverWait(driver, 10).until(EC.presence_of_element_located((By.CSS_SELECTOR, "body > div.index-main > div > div.desk-front.sign-flow.clearfix.sign-flow-simple > div.index-tab-navs > div > a.active")))
botton = driver.find_element_by_css_selector('body > div.index-main > div > div.desk-front.sign-flow.clearfix.sign-flow-simple > div.view.view-signin > div.qrcode-signin-container > div.qrcode-signin-step1 > div.qrcode-signin-cut-button > span')
botton.click()
form = driver.find_element_by_css_selector('body > div.index-main > div > div.desk-front.sign-flow.clearfix.sign-flow-simple > div.view.view-signin > form > div.group-inputs > div.account.input-wrapper > input[type="text"]')
pas = driver.find_element_by_css_selector('body > div.index-main > div > div.desk-front.sign-flow.clearfix.sign-flow-simple > div.view.view-signin > form > div.group-inputs > div.verification.input-wrapper > input[type="password"]')
sub = driver.find_element_by_css_selector('body > div.index-main > div > div.desk-front.sign-flow.clearfix.sign-flow-simple > div.view.view-signin > form > div.button-wrapper.command > button')
form.send_keys(account)
pas.send_keys(password)
sub.click()
try:
print('请手动输入验证码')
driver.implicitly_wait(10)
driver.find_element_by_css_selector('#root > div > div:nth-child(2) > header > div > div.SearchBar > button')
except NoSuchElementException:
sub.click()
except:
putcookies(account,password)
#滑动页面
def change_page(num):
WebDriverWait(driver,10).until(EC.presence_of_element_located((By.CSS_SELECTOR,'#root > div > div:nth-child(2) > header > div > div.SearchBar > button')))
for i in range(num):
driver.execute_script('window.scrollTo(0, document.body.scrollHeight)')
time.sleep(3)
#解析页面
def findinf(html):
soup = BeautifulSoup(html,'lxml')
r = re.compile('(\d+)')
links = soup.find_all('div',class_='Card TopstoryItem')
for link in links:
try:
maininf = link.find(class_='Feed-meta-item').get_text()[-3:]#话题
writer = link.find(class_='AuthorInfo-head').get_text()#作者
except:
continue
try:
intd = link.find('div',class_='RichText AuthorInfo-badgeText').string#作者个人介绍
except:
intd = ''
title = link.find('h2',class_='ContentItem-title').get_text()#标题
href = 'https://www.zhihu.com' + link.find('h2',class_='ContentItem-title').a['href']#文章链接
try:
support = link.find(class_='Button VoteButton VoteButton--up').get_text()#点赞
except:
support = link.find(class_='Button LikeButton ContentItem-action').get_text()#点赞
try:
talking = r.match(link.find('button',class_='Button ContentItem-action Button--plain').get_text()[:-3]).group()#评论数
except:
talking = ''
content = link.find('span',class_='RichText CopyrightRichText-richText').get_text()#摘要
yield {
'maininf': maininf,
'writer':writer,
'intd':intd,
'title':title,
'support':support,
'talking':talking,
'content':content,
'href':href,
}
#创建一个文件夹
def make(path):
if not os.path.exists(path):
os.makedirs(path)
#保存数据
def save_to_csv(inf,path):
with open(path + '知乎文章信息概要采集.csv','a') as f:
writer = csv.writer(f)
writer.writerow(['标题','作者','话题','作者个人介绍','点赞数','评论数','文章链接','摘要'])
try:
for i in inf:
writer.writerow([i['title'],i['writer'],i['maininf'],i['intd'],i['support'],i['talking'],i['href'],i['content']])
except:
pass
#主函数
def main(account,password,num):
path = 'D:/数据/知乎文章/'
putcookies(account,password)
change_page(num)
inf = findinf(driver.page_source)
make(path)
print('---'*43)
print('{:^60}'.format('知乎文章概要'))
print("***"*43)
for i in findinf(driver.page_source):
print('标题:{:<10s}'.format(i['title']))
print('作者:{:>3s}'.format(i['writer']),end = ' '*5)
print("话题:{:>3s}".format(i['maininf']))
print('作者个人介绍:')
print('{:<5s}'.format(i['intd']))
print('点赞数:{:<2s}'.format(i['support']),end = ' '*5)
print("评论数:{:3s}".format(i['talking']))
print("文章链接:" + i['href'])
print("摘要：")
print('{:<5s}'.format(i['content']))
print('---' *43)
save_to_csv(inf,path)
#执行程序
if __name__ == '__main__':
num = int(input('请输入要爬取的页面数：'))
account = input("请输入知乎账号：")
password = input("请输入知乎密码：")
time_start = time.time()
main(account,password,num)
print("^^^"*43)
print("共耗时{}秒".format(time.time()-time_start))
driver.quit()
爬取的结果得到了文章概要信息，可以做一个文章信息的参考。