Beautifulsoup没有达到一个子元素

Question

我写了下面的代码试图刮谷歌学术页面

import requests as req 
from bs4 import BeautifulSoup as soup 

url = r'https://scholar.google.com/scholar?hl=en&q=Sustainability and the measurement of wealth: further reflections' 

session = req.Session() 
content = session.get(url) 
html2bs = soup(content.content, 'lxml') 
gs_cit = html2bs.select('#gs_cit') 
gs_citd = html2bs.find('div', {'id':"gs_citd"}) 
gs_cit1 = html2bs.find('div', {'id':"gs_cit1"}) 

但gs_citd给我只有这一行<div aria-live="assertive" id="gs_citd"></div>，并在其下方没有达到任何水平。 gs_cit1也返回None。

由于出现这一形象

在我要到达突出显示类要能抓住读者预约。

请问您能帮忙吗？

Answer 1

好的，所以我想通了。我使用了python的selenium模块，它创建了一个虚拟浏览器，如果你愿意的话，它可以让你执行一些操作，比如点击链接并获得HTML输出。在解决这个问题时遇到了另一个问题，那就是页面必须被加载，否则它只是在弹出的div中返回内容“Loading ...”，所以我使用了Python时间模块time.sleep(2) 2秒，要加载的内容。然后，我使用BeautifulSoup解析生成的HTML输出，以找到具有类“gs_citi”的锚标记。然后从锚中拉出href，并将其放入带有“requests”python模块的请求中。最后，我将解码的响应写入本地文件 - scholar.bib。 https://gist.github.com/guylaor/3eb9e7ff2ac91b7559625262b8a6dd5f

然后通过Python文件签署允许使用这些指令停止防火墙问题： Add Python to OS X Firewall Options?

以下是我的代码

我在这里使用这些说明安装chromedriver和硒对我的Mac用于生成输出文件“scholar.bib”：

import os 
import time 
from selenium import webdriver 
from bs4 import BeautifulSoup as soup 
import requests as req 

# Setup Selenium Chrome Web Driver 
chromedriver = "/usr/local/bin/chromedriver" 
os.environ["webdriver.chrome.driver"] = chromedriver 
driver = webdriver.Chrome(chromedriver) 

# Navigate in Chrome to specified page. 
driver.get("https://scholar.google.com/scholar?hl=en&q=Sustainability and the measurement of wealth: further reflections") 

# Find "Cite" link by looking for anchors that contain "Cite" - second link selected "[1]" 
link = driver.find_elements_by_xpath('//a[contains(text(), "' + "Cite" + '")]')[1] 
# Click the link 
link.click() 

print("Waiting for page to load...") 
time.sleep(2) # Sleep for 2 seconds 

# Get Page source after waiting for 2 seconds of current page in Chrome 
source = driver.page_source 

# We are done with the driver so quit. 
driver.quit() 

# Use BeautifulSoup to parse the html source and use "html.parser" as the Parser 
soupify = soup(source, 'html.parser') 

# Find anchors with the class "gs_citi" 
gs_citt = soupify.find('a',{"class":"gs_citi"}) 

# Get the href attribute of the first anchor found 
href = gs_citt['href'] 

print("Fetching: ", href) 

# Instantiate a new requests session 
session = req.Session() 

# Get the response object of href 
content = session.get(href) 

# Get the content and then decode() it. 
bibtex_html = content.content.decode() 

# Write the decoded data to a file named scholar.bib 
with open("scholar.bib","w") as file: 
    file.writelines(bibtex_html) 

希望这有助于任何寻找解决方案的人出。

Scholar.bib文件：要刮

@article{arrow2013sustainability, 
    title={Sustainability and the measurement of wealth: further reflections}, 
    author={Arrow, Kenneth J and Dasgupta, Partha and Goulder, Lawrence H and Mumford, Kevin J and Oleson, Kirsten}, 
    journal={Environment and Development Economics}, 
    volume={18}, 
    number={4}, 
    pages={504--516}, 
    year={2013}, 
    publisher={Cambridge University Press} 
}