Download pdf using urllib?

问题

I am trying to download a pdf file from a website using urllib. This is what i got so far:

import urllib

def download_file(download_url):
    web_file = urllib.urlopen(download_url)
    local_file = open('some_file.pdf', 'w')
    local_file.write(web_file.read())
    web_file.close()
    local_file.close()

if __name__ == 'main':
    download_file('http://www.example.com/some_file.pdf')

When i run this code, all I get is an empty pdf file. What am I doing wrong?

回答1:

Here is an example that works:

import urllib2

def main():
    download_file("http://mensenhandel.nl/files/pdftest2.pdf")

def download_file(download_url):
    response = urllib2.urlopen(download_url)
    file = open("document.pdf", 'wb')
    file.write(response.read())
    file.close()
    print("Completed")

if __name__ == "__main__":
    main()

回答2:

Change open('some_file.pdf', 'w') to open('some_file.pdf', 'wb'), pdf files are binary files so you need the 'b'. This is true with pretty much any file that you can't open in a text editor.

回答3:

Try to use urllib.retrieve (Python 3) and just do that:

from urllib.request import urlretrieve

def download_file(download_url):
    urlretrieve(download_url, 'path_to_save_plus_some_file.pdf')

if __name__ == 'main':
    download_file('http://www.example.com/some_file.pdf')

回答4:

The tried the above code, they work fine in some cases, but for some website with pdf embedded in it, you might get an error like HTTPError: HTTP Error 403: Forbidden. Such websites have some server security features which will block known bots. In case of urllib it uses a header which will say something like ====> python urllib/3.3.0. So I would suggest adding a custom header too in request module of urllib as shown below.

from urllib.request import Request, urlopen 
import requests  
url="https://realpython.com/python-tricks-sample-pdf"  
import urllib.request  
req = urllib.request.Request(url, headers={'User-Agent': 'Mozilla/5.0'})  
r = requests.get(url)

with open("<location to dump pdf>/<name of file>.pdf", "wb") as code:
    code.write(r.content)

回答5:

I would suggest using following lines of code

import urllib.request
import shutil
url = "link to your website for pdf file to download"
output_file = "local directory://name.pdf"
with urllib.request.urlopen(url) as response, open(output_file, 'wb') as out_file:
     shutil.copyfileobj(response, out_file)

来源：https://stackoverflow.com/questions/24844729/download-pdf-using-urllib

标签

python

pdf

urllib