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Web scraping with Python and beautifulsoup: What is saved by the BeautifulSoup function?

This question follows this previous question. I want to scrape data from a betting site using Python. I first tried to follow this tutorial, but the problem is that the site tipico is not available from Switzerland. I thus chose another betting site: Winamax. In the tutorial, the webpage tipico is first inspected, in order to find where the betting rates are located in the html file. In the tipico webpage, they were stored in buttons of class “c_but_base c_but". By writing the following lines, the rates could therefore be saved and printed using the Beautiful soup module:
from bs4 import BeautifulSoup
import urllib.request
import re
url = "https://www.tipico.de/de/live-wetten/"
try:
page = urllib.request.urlopen(url)
except:
print(“An error occured.”)
soup = BeautifulSoup(page, ‘html.parser’)
regex = re.compile(‘c_but_base c_but’)
content_lis = soup.find_all(‘button’, attrs={‘class’: regex})
print(content_lis)
I thus tried to do the same with the webpage Winamax. I inspected the page and found that the betting rates were stored in buttons of class "ui-touchlink-needsclick price odd-price". See the code below:
from bs4 import BeautifulSoup
import urllib.request
import re
url = "https://www.winamax.fr/paris-sportifs/sports/1/7/4"
try:
page = urllib.request.urlopen(url)
except Exception as e:
print(f"An error occurred: {e}")
soup = BeautifulSoup(page, 'html.parser')
regex = re.compile('ui-touchlink-needsclick price odd-price')
content_lis = soup.find_all('button', attrs={'class': regex})
print(content_lis)
The problem is that it prints nothing: Python does not find elements of such class (right?). I thus tried to print the soup object in order to see what the BeautifulSoup function was exactly doing. I added this line
print(soup)
When printing it (I do not show it the print of soup because it is too long), I notice that this is not the same text as what appears when I do a right click "inspect" of the Winamax webpage. So what is the BeautifulSoup function exactly doing? How can I store the betting rates from the Winamax website using BeautifulSoup?
EDIT: I have never coded in html and I'm a beginner in Python, so some terminology might be wrong, that's why some parts are in italics.

That's because the website is using JavaScript to display these details and BeautifulSoup does not interact with JS on it's own.
First try to find out if the element you want to scrape is present in the page source, if so you can scrape, pretty much everything! In your case the button/span tag's were not in the page source(meaning hidden or it's pulled through a script)
No <button> tag in the page source :
So I suggest using Selenium as the solution, and I tried a basic scrape of the website.
Here is the code I used :
from selenium import webdriver
option = webdriver.ChromeOptions()
option.add_argument('--headless')
option.binary_location = r'Your chrome.exe file path'
browser = webdriver.Chrome(executable_path=r'Your chromedriver.exe file path', options=option)
browser.get(r"https://www.winamax.fr/paris-sportifs/sports/1/7/4")
span_tags = browser.find_elements_by_tag_name('span')
for span_tag in span_tags:
print(span_tag.text)
browser.quit()
This is the output:
There are some junk data present in this output, but that's for you to figure out what you need and what you don't!

python crawling text from <em></em>

Hi, I want to get the text(number 18) from em tag as shown in the picture above.
When I ran my code, it did not work and gave me only empty list. Can anyone help me? Thank you~
here is my code.
from urllib.request import urlopen
from bs4 import BeautifulSoup
url = 'https://blog.naver.com/kwoohyun761/221945923725'
html = urlopen(url)
soup = BeautifulSoup(html, 'lxml')
likes = soup.find_all('em', class_='u_cnt _count')
print(likes)

When you disable javascript you'll see that the like count is loaded dynamically, so you have to use a service that renders the website and then you can parse the content.
You can use an API: https://www.scraperapi.com/
Or run your own for example: https://github.com/scrapinghub/splash
EDIT:
First of all, I missed that you were using urlopen incorrectly the correct way is described here: https://docs.python.org/3/howto/urllib2.html . Assuming you are using python3, which seems to be the case judging by the print statement.
Furthermore: looking at the issue again it is a bit more complicated. When you look at the source code of the page it actually loads an iframe and in that iframe you have the actual content: Hit ctrl + u to see the source code of the original url, since the side seems to block the browser context menu.
So in order to achieve your crawling objective you have to first grab the initial page and then grab the page you are interested in:
from urllib.request import urlopen
from bs4 import BeautifulSoup
# original url
url = "https://blog.naver.com/kwoohyun761/221945923725"
with urlopen(url) as response:
html = response.read()
soup = BeautifulSoup(html, 'lxml')
iframe = soup.find('iframe')
# iframe grabbed, construct real url
print(iframe['src'])
real_url = "https://blog.naver.com" + iframe['src']
# do your crawling
with urlopen(real_url) as response:
html = response.read()
soup = BeautifulSoup(html, 'lxml')
likes = soup.find_all('em', class_='u_cnt _count')
print(likes)
You might be able to avoid one round trip by analyzing the original url and the URL in the iframe. At first glance it looked like the iframe url can be constructed from the original url.
You'll still need a rendered version of the iframe url to grab your desired value.
I don't know what this site is about, but it seems they do not want to get crawled maybe you respect that.

Accessing tabular data via hyperlinks with BeautifulSoup

There's something I still don't understand about using BeautifulSoup. I can use this to parse the raw HTML of a webpage, here "example_website.com":
from bs4 import BeautifulSoup # load BeautifulSoup class
import requests
r = requests.get("http://example_website.com")
data = r.text
soup = BeautifulSoup(data)
# soup.find_all('a') grabs all elements with <a> tag for hyperlinks
Then, to retrieve and print all elements with the 'href' attribute, we can use a for loop:
for link in soup.find_all('a'):
print(link.get('href'))
What I don't understand: I have a website with several webpages, and each webpage lists several hyperlinks to a single webpage with tabular data.
I can use BeautifulSoup to parse the homepage, but how do I use the same Python script to scrape page 2, page 3, and so on? How do you "access" the contents found via the 'href' links?
Is there a way to write a python script to do this? Should I be using a spider?

You can do that with requests+BeautifulSoup for sure. It would be of a blocking nature, since you would process the extracted links one by one and you would not proceed to the next link until you are done with the current. Sample implementation:
from urlparse import urljoin
from bs4 import BeautifulSoup
import requests
with requests.Session() as session:
r = session.get("http://example_website.com")
data = r.text
soup = BeautifulSoup(data)
base_url = "http://example_website.com"
for link in soup.find_all('a'):
url = urljoin(base_url, link.get('href'))
r = session.get(url)
# parse the subpage
Though, it may quickly get complex and slow.
You may need to switch to Scrapy web-scraping framework which makes web-scraping, crawling, following the links easy (check out CrawlSpider with link extractors), fast and in a non-blocking nature (it is based on Twisted).

How to use CSS selectors to retrieve specific links lying in some class using BeautifulSoup?

I am new to Python and I am learning it for scraping purposes I am using BeautifulSoup to collect links (i.e href of 'a' tag). I am trying to collect the links under the "UPCOMING EVENTS" tab of site http://allevents.in/lahore/. I am using Firebug to inspect the element and to get the CSS path but this code returns me nothing. I am looking for the fix and also some suggestions for how I can choose proper CSS selectors to retrieve desired links from any site. I wrote this piece of code:
from bs4 import BeautifulSoup
import requests
url = "http://allevents.in/lahore/"
r = requests.get(url)
data = r.text
soup = BeautifulSoup(data)
for link in soup.select( 'html body div.non-overlay.gray-trans-back div.container div.row div.span8 div#eh-1748056798.events-horizontal div.eh-container.row ul.eh-slider li.h-item div.h-meta div.title a[href]'):
print link.get('href')

The page is not the most friendly in the use of classes and markup, but even so your CSS selector is too specific to be useful here.
If you want Upcoming Events, you want just the first <div class="events-horizontal">, then just grab the <div class="title"><a href="..."></div> tags, so the links on titles:
upcoming_events_div = soup.select_one('div.events-horizontal')
for link in upcoming_events_div.select('div.title a[href]'):
print(link['href'])
Note that you should not use r.text; use r.content and leave decoding to Unicode to BeautifulSoup. See Encoding issue of a character in utf-8

import bs4 , requests
res = requests.get("http://allevents.in/lahore/")
soup = bs4.BeautifulSoup(res.text)
for link in soup.select('a[property="schema:url"]'):
print link.get('href')
This code will work fine!!

get all links from html even with show more link

I am using python and beautifulsoup for html parsing.
I am using the following code :
from BeautifulSoup import BeautifulSoup
import urllib2
import re
url = "http://www.wikipathways.org//index.php?query=signal+transduction+pathway&species=Homo+sapiens&title=Special%3ASearchPathways&doSearch=1&ids=&codes=&type=query"
main_url = urllib2.urlopen(url)
content = main_url.read()
soup = BeautifulSoup(content)
for a in soup.findAll('a',href=True):
print a[href]
but I am not getting output links like :
http://www.wikipathways.org/index.php/Pathway:WP26
and also imp thing is there are 107 pathways. but I will not get all the links as other lins depends on "show links" at the bottom of the page.
so, how can I get all the links (107 links) from that url?

Your problem is line 8, content = url.read(). You're not actually reading the webpage, you're actually just doing nothing (If anything, you should be getting an error).
main_url is what you want to read, so change line 8 to:
content = main_url.read()
You also have another error, print a[href]. href should be a string, so it should be:
print a['href']

I would suggest using lxml its faster and better for parsing html worth investing the time to learn it.
from lxml.html import parse
dom = parse('http://www.wikipathways.org//index.php?query=signal+transduction+pathway&species=Homo+sapiens&title=Special%3ASearchPathways&doSearch=1&ids=&codes=&type=query').getroot()
links = dom.cssselect('a')
That should get you going.