[FIXED] Download all pdf files from a website using Python

Issue

I have followed several online guides in an attempt to build a script that can identify and download all pdfs from a website to save me from doing it manually. Here is my code so far:

from urllib import request
from bs4 import BeautifulSoup
import re
import os
import urllib

# connect to website and get list of all pdfs
url="http://www.gatsby.ucl.ac.uk/teaching/courses/ml1-2016.html"
response = request.urlopen(url).read()
soup= BeautifulSoup(response, "html.parser")     
links = soup.find_all('a', href=re.compile(r'(.pdf)'))


# clean the pdf link names
url_list = []
for el in links:
    url_list.append(("http://www.gatsby.ucl.ac.uk/teaching/courses/" + el['href']))
#print(url_list)


# download the pdfs to a specified location
for url in url_list:
    print(url)
    fullfilename = os.path.join('E:\webscraping', url.replace("http://www.gatsby.ucl.ac.uk/teaching/courses/ml1-2016/", "").replace(".pdf",""))
    print(fullfilename)
    request.urlretrieve(url, fullfilename)

The code can appear to find all the pdfs (uncomment the print(url_list) to see this). However, it fails at the download stage. In particular I get this error and I am not able to understand what's gone wrong:

E:\webscraping>python get_pdfs.py
http://www.gatsby.ucl.ac.uk/teaching/courses/http://www.gatsby.ucl.ac.uk/teaching/courses/ml1-2016/cribsheet.pdf
E:\webscraping\http://www.gatsby.ucl.ac.uk/teaching/courses/cribsheet
Traceback (most recent call last):
  File "get_pdfs.py", line 26, in <module>
    request.urlretrieve(url, fullfilename)
  File "C:\Users\User\Anaconda3\envs\snake\lib\urllib\request.py", line 248, in urlretrieve
    with contextlib.closing(urlopen(url, data)) as fp:
  File "C:\Users\User\Anaconda3\envs\snake\lib\urllib\request.py", line 223, in urlopen
    return opener.open(url, data, timeout)
  File "C:\Users\User\Anaconda3\envs\snake\lib\urllib\request.py", line 532, in open
    response = meth(req, response)
  File "C:\Users\User\Anaconda3\envs\snake\lib\urllib\request.py", line 642, in http_response
    'http', request, response, code, msg, hdrs)
  File "C:\Users\User\Anaconda3\envs\snake\lib\urllib\request.py", line 570, in error
    return self._call_chain(*args)
  File "C:\Users\User\Anaconda3\envs\snake\lib\urllib\request.py", line 504, in _call_chain
    result = func(*args)
  File "C:\Users\User\Anaconda3\envs\snake\lib\urllib\request.py", line 650, in http_error_default
    raise HTTPError(req.full_url, code, msg, hdrs, fp)
urllib.error.HTTPError: HTTP Error 404: Not Found

Can somebody help me please?

Solution

Check out the following implementation. I've used requests module instead of urllib to do the download. Moreover, I've used .select() method instead of .find_all() to avoid using re.

import os
import requests
from urllib.parse import urljoin
from bs4 import BeautifulSoup

url = "http://www.gatsby.ucl.ac.uk/teaching/courses/ml1-2016.html"

#If there is no such folder, the script will create one automatically
folder_location = r'E:\webscraping'
if not os.path.exists(folder_location):os.mkdir(folder_location)

response = requests.get(url)
soup= BeautifulSoup(response.text, "html.parser")     
for link in soup.select("a[href$='.pdf']"):
    #Name the pdf files using the last portion of each link which are unique in this case
    filename = os.path.join(folder_location,link['href'].split('/')[-1])
    with open(filename, 'wb') as f:
        f.write(requests.get(urljoin(url,link['href'])).content)

Answered By - SIM