python: 带有 BeautifulSoup 的 Google 搜索刮板

Question

目标：传递一个搜索字符串在 google 上搜索并抓取 url、标题和与 url 标题一起发布的小描述。

我有以下代码，目前我的代码只给出前 10 个结果，这是一页的默认谷歌限制。我不确定如何在网页抓取期间真正处理分页。此外，当我查看实际页面结果和打印出来的内容时，存在差异。我也不确定解析 span 元素的最佳方法是什么。

到目前为止，我的跨度如下，我想删除 <em> 元素并连接其余的刺。最好的方法是什么？

<span class="st">The <em>Beautiful Soup</em> Theater Collective was founded in the summer of 2010 by its Artistic Director, Steven Carl McCasland. A continuation of a student group he <b>...</b><br /></span

代码：

from BeautifulSoup import BeautifulSoup
import urllib, urllib2

def google_scrape(query):
    address = "http://www.google.com/search?q=%s&num=100&hl=en&start=0" % (urllib.quote_plus(query))
    request = urllib2.Request(address, None, {'User-Agent':'Mosilla/5.0 (Macintosh; Intel Mac OS X 10_7_4) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.57 Safari/536.11'})
    urlfile = urllib2.urlopen(request)
    page = urlfile.read()
    soup = BeautifulSoup(page)

    linkdictionary = {}

    for li in soup.findAll('li', attrs={'class':'g'}):
        sLink = li.find('a')
        print sLink['href']
        sSpan = li.find('span', attrs={'class':'st'})
        print sSpan

    return linkdictionary

if __name__ == '__main__':
    links = google_scrape('beautifulsoup')

我的输出如下所示：

http://www.crummy.com/software/BeautifulSoup/
<span class="st"><em>Beautiful Soup</em>: a library designed for screen-scraping HTML and XML.<br /></span>
http://pypi.python.org/pypi/BeautifulSoup/3.2.1
<span class="st"><span class="f">Feb 16, 2012 &ndash; </span>HTML/XML parser for quick-turnaround applications like screen-scraping.<br /></span>
http://www.beautifulsouptheatercollective.org/
<span class="st">The <em>Beautiful Soup</em> Theater Collective was founded in the summer of 2010 by its Artistic Director, Steven Carl McCasland. A continuation of a student group he <b>...</b><br /></span>
http://lxml.de/elementsoup.html
<span class="st"><em>BeautifulSoup</em> is a Python package that parses broken HTML, just like lxml supports it based on the parser of libxml2. <em>BeautifulSoup</em> uses a different parsing <b>...</b><br /></span>
https://launchpad.net/beautifulsoup/
<span class="st">The discussion group is at: http://groups.google.com/group/<em>beautifulsoup</em> &middot; Home page <b>...</b> <em>Beautiful Soup</em> 4.0 series is  the current focus of development <b>...</b><br /></span>
http://www.poetry-online.org/carroll_beautiful_soup.htm
<span class="st"><em>Beautiful Soup BEAUTIFUL Soup</em>, so rich and green, Waiting in a hot tureen! Who for such dainties would not stoop? Soup of the evening, <em>beautiful Soup</em>!<br /></span>
http://www.youtube.com/watch?v=hDG73IAO5M8
<span class="st"><span class="f">Jul 6, 2009 &ndash; </span>taken from the motion picture &quot;Alice in wonderland&quot; (1999) http://www.imdb.com/<wbr>title/tt0164993/<br /></wbr></span>
http://www.soupsong.com/
<span class="st">A witty and substantive research effort on the history of soup and food in all cultures, with over 400 pages of recipes, quotations, stories, traditions, literary <b>...</b><br /></span>
http://www.facebook.com/beautifulsouptc
<span class="st">To connect with The <em>Beautiful Soup</em> Theater Collective, sign up for Facebook <b>...</b> We&#39;re thrilled to announce the cast of <em>Beautiful Soup&#39;s</em> upcoming production of <b>...</b><br /></span>
http://blog.dispatched.ch/webscraping-with-python-and-beautifulsoup/
<span class="st"><span class="f">Mar 15, 2009 &ndash; </span>Recently my life has been a hype; partly due to my upcoming Python addiction. There&#39;s simply no way around it; so I should better confess it in <b>...</b><br /></span>

Google 搜索页面结果具有以下结构：

<li class="g">
<div class="vsc" sig="bl_" bved="0CAkQkQo" pved="0CAgQkgowBQ">
<h3 class="r">
<div class="vspib" aria-label="Result details" role="button" tabindex="0">
<div class="s">
<div class="f kv">
<div id="poS5" class="esc slp" style="display:none">
<div class="f slp">3 answers&nbsp;-&nbsp;Jan 16, 2009</div>
<span class="st">
I read this without finding the solution:
<b>...</b>
The "normal" way is to: Go to the
<em>Beautiful Soup</em>
web site,
<b>...</b>
Brian beat me too it, but since I already have
<b>...</b>
<br>
</span>
</div>
<div>
</div>
<h3 id="tbpr_6" class="tbpr" style="display:none">
</li>

每个搜索结果都列在<li> 元素下。

Answer 1

这个列表推导会去除标签。

>>> sSpan
<span class="st">The <em>Beautiful Soup</em> Theater Collective was founded in the summer of 2010 by its Artistic Director, Steven Carl McCasland. A continuation of a student group he <b>...</b><br /></span>
>>> [em.replaceWithChildren() for em in sSpan.findAll('em')]
[None]
>>> sSpan
<span class="st">The Beautiful Soup Theater Collective was founded in the summer of 2010 by its Artistic Director, Steven Carl McCasland. A continuation of a student group he <b>...</b><br /></span>

Answer 2

我构造了一个简单的html正则表达式，然后在清理后的字符串上调用replace函数来去除点

import re

p = re.compile(r'<.*?>')
print p.sub('',str(sSpan)).replace('.','')

之前

<span class="st">The <em>Beautiful Soup</em> is a collection of all the pretty places you would rather be. All posts are credited via a click through link. For further inspiration of pretty things, <b>...</b><br /></span>

之后

The Beautiful Soup is a collection of all the pretty places you would rather be All posts are credited via a click through link For further inspiration of pretty things, 

Answer 3

要从span 标记中获取文本元素，您可以使用.text/get_text() 方法beautifulsoupprovides。 Bs4 做所有艰苦的提升，你不必担心如何摆脱<em> 标签。

代码和full example（谷歌won't show more than ~400 results。）：

from bs4 import BeautifulSoup
import requests, lxml, urllib.parse


def print_extracted_data_from_url(url):
    headers = {
        "User-Agent":
        "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.102 Safari/537.36 Edge/18.19582"
    }
    response = requests.get(url, headers=headers).text

    soup = BeautifulSoup(response, 'lxml')

    print(f'Current page: {int(soup.select_one(".YyVfkd").text)}')
    print(f'Current URL: {url}')
    print()

    for container in soup.findAll('div', class_='tF2Cxc'):
        head_text = container.find('h3', class_='LC20lb DKV0Md').text
        head_sum = container.find('div', class_='IsZvec').text
        head_link = container.a['href']
        print(head_text)
        print(head_sum)
        print(head_link)
        print()

    return soup.select_one('a#pnnext')


def scrape():
    next_page_node = print_extracted_data_from_url(
        'https://www.google.com/search?hl=en-US&q=coca cola')

    while next_page_node is not None:
        next_page_url = urllib.parse.urljoin('https://www.google.com',
                                             next_page_node['href'])

        next_page_node = print_extracted_data_from_url(next_page_url)

scrape()

输出：

Results via beautifulsoup

Current page: 1
Current URL: https://www.google.com/search?hl=en-US&q=coca cola

The Coca-Cola Company: Refresh the World. Make a Difference
We are here to refresh the world and make a difference. Learn more about the Coca-Cola Company, our brands, and how we strive to do business the right way.‎Contact Us · ‎Careers · ‎Coca-Cola · ‎Coca-Cola System
https://www.coca-colacompany.com/home

Coca-Cola
2021 The Coca-Cola Company, all rights reserved. COCA-COLA®, "TASTE THE FEELING", and the Contour Bottle are trademarks of The Coca-Cola Company.
https://www.coca-cola.com/

Together Tastes Better | Coca-Cola®
Coca-Cola is pairing up with celebrity chefs, talented athletes and more surprise guests all summer long to bring you and your loved ones together over the love ...
https://us.coca-cola.com/

---

或者，您可以使用来自 SerpApi 的 Google Search Engine Results API 来实现此目的。这是一个带有免费计划的付费 API 查看Playground 进行测试。

要集成的代码：

import os
from serpapi import GoogleSearch

def scrape():
  
  params = {
    "engine": "google",
    "q": "coca cola",
    "api_key": os.getenv("API_KEY"),
  }

  search = GoogleSearch(params)
  results = search.get_dict()

  print(f"Current page: {results['serpapi_pagination']['current']}")

  for result in results["organic_results"]:
      print(f"Title: {result['title']}\nLink: {result['link']}\n")

  while 'next' in results['serpapi_pagination']:
      search.params_dict["start"] = results['serpapi_pagination']['current'] * 10
      results = search.get_dict()

      print(f"Current page: {results['serpapi_pagination']['current']}")

      for result in results["organic_results"]:
          print(f"Title: {result['title']}\nLink: {result['link']}\n")

输出：

Results from SerpApi

Current page: 1
Title: The Coca-Cola Company: Refresh the World. Make a Difference
Link: https://www.coca-colacompany.com/home

Title: Coca-Cola
Link: https://www.coca-cola.com/

Title: Together Tastes Better | Coca-Cola®
Link: https://us.coca-cola.com/

Title: Coca-Cola - Wikipedia
Link: https://en.wikipedia.org/wiki/Coca-Cola

Title: Coca-Cola - Home | Facebook
Link: https://www.facebook.com/Coca-Cola/

Title: The Coca-Cola Company | LinkedIn
Link: https://www.linkedin.com/company/the-coca-cola-company

Title: Coca-Cola UNITED: Home
Link: https://cocacolaunited.com/

Title: World of Coca-Cola: Atlanta Museum & Tourist Attraction
Link: https://www.worldofcoca-cola.com/

Current page: 2
Title: Coca-Cola (@CocaCola) | Twitter
Link: https://twitter.com/cocacola?lang=en

免责声明，我为 SerpApi 工作。