Broken Link Checker Fails Head Requests - python

I am building a broken link checker using Python 3.4 to help ensure the quality of a large collection of articles that I manage. Initially I was using GET requests to check if a link was viable, however I and trying to be as nice as possible when pinging the URLs I'm checking, so I both ensure that I do not check a URL that is tested as working more than once and I have attempted to do just head requests.
However, I have found a site that causes this to simply stop. It neither throws an error, nor opens:
https://www.icann.org/resources/pages/policy-2012-03-07-en
The link itself is fully functional. So ideally I'd like to find a way to process similar links. This code in Python 3.4 will reproduce the issue:
import urllib
import urllib.request
URL = 'https://www.icann.org/resources/pages/policy-2012-03-07-en'
req=urllib.request.Request(URL, None, {'User-Agent': 'Mozilla/5.0 (X11; Linux i686; G518Rco3Yp0uLV40Lcc9hAzC1BOROTJADjicLjOmlr4=) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/44.0.2403.157 Safari/537.36','Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8','Accept-Charset': 'ISO-8859-1,utf-8;q=0.7,*;q=0.3','Accept-Encoding': 'gzip, deflate, sdch','Accept-Language': 'en-US,en;q=0.8','Connection': 'keep-alive'}, method='HEAD')>>> from http.cookiejar import CookieJar
cj = CookieJar()
opener = urllib.request.build_opener(urllib.request.HTTPCookieProcessor(cj))
response = opener.open(req)
As it does not throw an error, I really do not know how to troubleshoot this further beyond narrowing it down to the link that halted the entire checker. How can I check if this link is valid?

From bs4 import BeautifulSoup,SoupStrainer
import urllib2
import requests
import re
import certifi
import ssl
ssl._create_default_https_context = ssl._create_unverified_context
def getStatus(url):
a=requests.get(url,verify=False)
report = str(a.status_code)
return report
alllinks=[]
passlinks=[]
faillinks=[]
html_page = urllib2.urlopen("https://link")
soup = BeautifulSoup(html_page,"html.parser")
for link in soup.findAll('a', attrs={'href': re.compile("^http*")}):
#print link.get('href')
status = getStatus(link.get('href'))
#print ('URL---->',link.get('href'),'Status---->',status)
link='URL---->',link.get('href'),'Status---->',status
alllinks.append(link)
if status == '200':
passlinks.append(link)
else:
faillinks.append(link)
print alllinks
print passlinks
print faillinks

Related

BeautifulSoup using Python keep returning null even though the element exists

I am running the following code to parse an amazon page using beautiful soup in Python but when I run the print line, I keep getting None. I am wondering whether I am doing something wrong or if theres an explanation/solution to this. Any help will be appreciated.
import requests
from bs4 import BeautifulSoup
URL = 'https://www.amazon.ca/Magnetic-Erase-Whiteboard-Bulletin-
Board/dp/B07GNVZKY2/ref=sr_1_3_sspa?keywords=whiteboard&qid=1578902710&s=office&sr=1-3-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEzOE5ZSkFGSDdCOFVDJmVuY3J5cHRlZElkPUEwMDM2ODA4M0dWMEtMWkI1U1hJJmVuY3J5cHRlZEFkSWQ9QTA0MDIwMjQxMEUwMzlMQ0pTQVlBJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ=='
headers = {"User-Agent": 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.117 Safari/537.36'}
page = requests.get(URL, headers=headers)
soup = BeautifulSoup(page.content, 'html.parser')
title = soup.find(id="productTitle")
print(title)
Your code is absolutely correct.
There seems to be some issue with the the parser that you have used (html.parser)
I used html5lib in place of html.parser and the code now works:
import requests
from bs4 import BeautifulSoup
URL = 'https://www.amazon.ca/Magnetic-Erase-Whiteboard-BulletinBoard/dp/B07GNVZKY2/ref=sr_1_3_sspa?keywords=whiteboard&qid=1578902710&s=office&sr=1-3-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEzOE5ZSkFGSDdCOFVDJmVuY3J5cHRlZElkPUEwMDM2ODA4M0dWMEtMWkI1U1hJJmVuY3J5cHRlZEFkSWQ9QTA0MDIwMjQxMEUwMzlMQ0pTQVlBJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ=='
headers = {"User-Agent": 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.117 Safari/537.36'}
page = requests.get(URL, headers=headers)
soup = BeautifulSoup(page.content, 'html5lib')
title = soup.find(id='productTitle')
print(title)
More Info not directly related to the answer:
For the other answer given to this question, I wasn't asked for a captcha when visiting the page.
However Amazon does change the response content if it detects that a bot is visiting the website: Remove the headers from requests.get() method, and try page.text
The default headers added by requests library lead to the identification of the request as being form a bot.
When requesting that page outside of a normal browser environment it asked for a captcha, I'd assume that's why the element doesn't exist.
Amazon probably has specific measures to counter "robots" accessing their pages, I suggest to look at their APIs to see if there's anything helpful instead of scraping the webpages directly.

BeautifulSoup Not Parsing HTML Correctly inside Try/Except Loop

I've got a problem parsing a document with BS4, and I'm not sure what's happening. The response code is OK, the url is fine, the proxies work, everything is great, proxy shuffling works as expected, but soup comes back blank using any parser other than html5lib. The soup that html5lib comes back with stops at the <body> tag.
I'm working in Colab and I've been able to run pieces of this function successfully in another notebook, and have gotten as far as being able to loop through a set of search results, make soup out of the links, and grab my desired data, but my target website eventually blocks me, so I have switched to using proxies.
check(proxy) is a helper function that checks a list of proxies before attempting to make a requests of my target site. The problem seems to have started when I included it in try/except. I'm speculating that maybe it's something to do with the try/except being included in a for loop --- idk.
What's confounding is that I know the site isn't blocking scrapers/robots generally, as I can use BS4 in another notebook piecemeal and get what I'm looking for.
from bs4 import BeautifulSoup as bs
from itertools import cycle
import time
from time import sleep
import requests
import random
head = {'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.70 Safari/537.36', "X-Requested-With": "XMLHttpRequest"}
ips = []
proxy_pool = cycle(ips)
def scrape_boxrec():
search_result_pages = [num for num in range(0, 22700, 20)]
random.shuffle(search_result_pages)
for i in search_result_pages:
search_results_page_attempt.append(i)
proxy = next(proxy_pool)
proxies = {
'http': proxy,
'https': proxy
}
if check(proxy) == True:
url = 'https://boxrec.com/en/locations/people?l%5Brole%5D=proboxer&l%5Bdivision%5D=&l%5Bcountry%5D=&l%5Bregion%5D=&l%5Btown%5D=&l_go=&offset=' + str(i)
try:
results_source = requests.get(url, headers=head, timeout=5, proxies=proxies)
results_content = results_source.content
res_soup = bs(results_content, 'html.parser')
# WHY IS IT NOT PARSING THIS PAGE CORRECTLY!!!!
except Exception as ex:
print(ex)
else:
print("Bad Proxy. Moving On")
def check(proxy):
check_url = 'https://httpbin.org/ip'
check_proxies = {
'http': proxy,
'https': proxy
}
try:
response = requests.get(check_url, proxies=check_proxies, timeout=5)
if response.status_code == 200:
return True
except:
return False
Since nobody took a crack at it I thought I would come back through and update on a solution - my use of "X-Requested-With": "XMLHttpRequest" in my head variable is what was causing the error. I'm still new to programming, especially with making HTTP requests, but I do know it has something to do with Ajax. Anyways, when I removed that bit from the headers attribute in my request BeautifulSoup parsed the document in full.
This answer as well as this one explains in a lot more detail that this is a common approach to prevent Cross Site Request Forgery, which is why my request was always coming back empty.

python requests & beautifulsoup bot detection

I'm trying to scrape all the HTML elements of a page using requests & beautifulsoup. I'm using ASIN (Amazon Standard Identification Number) to get the product details of a page. My code is as follows:
from urllib.request import urlopen
import requests
from bs4 import BeautifulSoup
url = "http://www.amazon.com/dp/" + 'B004CNH98C'
response = urlopen(url)
soup = BeautifulSoup(response, "html.parser")
print(soup)
But the output doesn't show the entire HTML of the page, so I can't do my further work with product details.
Any help on this?
EDIT 1:
From the given answer, It shows the markup of the bot detection page. I researched a bit & found two ways to breach it :
I might need to add a header in the requests, but I couldn't understand what should be the value of header.
Use Selenium.
Now my question is, do both of the ways provide equal support?
It is better to use fake_useragent here for making things easy. A random user agent sends request via real world browser usage statistic. If you don't need dynamic content, you're almost always better off just requesting the page content over HTTP and parsing it programmatically.
import requests
from fake_useragent import UserAgent
headers = {'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.95 Safari/537.36'}
ua=UserAgent()
hdr = {'User-Agent': ua.random,
'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
'Accept-Charset': 'ISO-8859-1,utf-8;q=0.7,*;q=0.3',
'Accept-Encoding': 'none',
'Accept-Language': 'en-US,en;q=0.8',
'Connection': 'keep-alive'}
url = "http://www.amazon.com/dp/" + 'B004CNH98C'
response = requests.get(url, headers=hdr)
print response.content
Selenium is used for browser automation and high level web scraping for dynamic contents.
As some of the comments already suggested, if you need to somehow interact with Javascript on a page, it is better to use selenium. However, regarding your first approach using a header:
import requests
from bs4 import BeautifulSoup
url = "http://www.amazon.com/dp/" + 'B004CNH98C'
headers = {'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.95 Safari/537.36'}
response = requests.get(url, headers=headers)
soup = BeautifulSoup(response.text,"html.parser")
These headers are a bit old, but should still work. By using them you are pretending that your request is coming from a normal webbrowser. If you use requests without such a header your code is basically telling the server that the request is coming from python, which most of the servers are rejecting right away.
Another alternative for you could also be fake-useragent maybe you can also have a try with this.
try this:
import requests
from bs4 import BeautifulSoup
url = "http://www.amazon.com/dp/" + 'B004CNH98C'
r = requests.get(url)
r = r.text
##options #1
# print r.text
soup = BeautifulSoup( r.encode("utf-8") , "html.parser")
### options 2
print(soup)

Problems with user agent on urllib

I wanted to get the HTML of web site but I cant get it due to the user agent I suppose. Because when I call uClient=ureq(my_url) I get an error like this: urllib.error.HTTPError: HTTP Error 403: Forbidden
This is the code:
from urllib.request import urlopen as ureq, Request
from bs4 import BeautifulSoup as soup
my_url= 'https://hsreplay.net/meta/#tab=matchups&sortBy=winrate'
ureq(Request(my_url, headers={'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:47.0) Gecko/20100101 Firefox/47.0'}))
uClient=ureq(my_url)
page_html=uClient.read()
uClient.close()
html=soup(page_html,"html.parser")
I have tried other methods of changing th user agent and other user agents, but it isn't work.
I'm pretty sure you will help. Thanks!!
What you did above is clearly a mess. The code should not run at all. Try the below way instead.
from bs4 import BeautifulSoup
from urllib.request import Request,urlopen
URL = "https://hsreplay.net/meta/#tab=matchups&sortBy=winrate"
req = Request(URL,headers={"User-Agent":"Mozilla/5.0"})
res = urlopen(req).read()
soup = BeautifulSoup(res,"lxml")
name = soup.find("h1").text
print(name)
Output:
HSReplay.net
Btw, you can scrape few items that are not javascript encrypted from that page. However, the core content of that page are generated dynamically so you can't grab them using urllib and BeautifulSoup. To get them you need to choose any browser simulator like selenium etc.

Python - Web scraping with Beautiful Soup

I am currently trying to reproduce a web scraping example with Beautiful Soup. However, I have to say I find it pretty unintuitive, which of course might alse be due to lack of experience. In case anyone could help me with an example I'd appreciate it. I cannot find much relevant information online. I would like to extract the first value (Dornum) of the following website: http://flow.gassco.no/
I only got this far:
import requests
page = requests.get("http://flow.gassco.no/")
from bs4 import BeautifulSoup
soup = BeautifulSoup(page, 'html.parser')
Thank you in advance!
Another way is to use current requests module.
You can pass user-agent like this:
import requests
from bs4 import BeautifulSoup
headers = {
'User-Agent': 'Mozilla/5.0 (Linux; Android 4.4.2; Nexus 4 Build/KOT49H) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/34.0.1847.114 Mobile Safari/537.36'
}
page = requests.get("http://flow.gassco.no/", headers=headers)
soup = BeautifulSoup(page.text, 'html.parser')
EDIT: To make this version work straightforward you can make a workaround with browser sessions.
You need to pass with requests.get a cookie that tells the site a session number, where Terms and Conditions are already accepted.
Run this code:
import requests
from bs4 import BeautifulSoup
url = "http://flow.gassco.no"
s = requests.Session()
r = s.get(url)
action = BeautifulSoup(r.content, 'html.parser').find('form').get('action') #this gives a "tail" of url whick indicates acceptance of Terms
s.get(url+action)
page = s.get(url).content
soup = BeautifulSoup(page, 'html.parser')
You need to learn how to use urllib, urllib2 first.
Some website shield spiders.
something like:
urllib2.request.add_header('User-Agent','Mozilla/5.0 (Linux; Android 4.4.2; Nexus 4 Build/KOT49H) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/34.0.1847.114 Mobile Safari/537.36')
Let website think you are Browser, not robot.

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