How do I download a file over HTTP using Python?

2018-12-31 01:42发布

I have a small utility that I use to download a MP3 from a website on a schedule and then builds/updates a podcast XML file which I've obviously added to iTunes.

The text processing that creates/updates the XML file is written in Python. I use wget inside a Windows .bat file to download the actual MP3 however. I would prefer to have the entire utility written in Python though.

I struggled though to find a way to actually down load the file in Python, thus why I resorted to wget.

So, how do I download the file using Python?

22条回答
琉璃瓶的回忆
2楼-- · 2018-12-31 02:15

Just for the sake of completeness, it is also possible to call any program for retrieving files using the subprocess package. Programs dedicated to retrieving files are more powerful than Python functions like urlretrieve. For example, wget can download directories recursively (-R), can deal with FTP, redirects, HTTP proxies, can avoid re-downloading existing files (-nc), and aria2 can do multi-connection downloads which can potentially speed up your downloads.

import subprocess
subprocess.check_output(['wget', '-O', 'example_output_file.html', 'https://example.com'])

In Jupyter Notebook, one can also call programs directly with the ! syntax:

!wget -O example_output_file.html https://example.com
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明月照影归
3楼-- · 2018-12-31 02:16

Python 3

  • urllib.request.urlopen

    import urllib.request
    response = urllib.request.urlopen('http://www.example.com/')
    html = response.read()
    
  • urllib.request.urlretrieve

    import urllib.request
    urllib.request.urlretrieve('http://www.example.com/songs/mp3.mp3', 'mp3.mp3')
    

Python 2

  • urllib2.urlopen (thanks Corey)

    import urllib2
    response = urllib2.urlopen('http://www.example.com/')
    html = response.read()
    
  • urllib.urlretrieve (thanks PabloG)

    import urllib
    urllib.urlretrieve('http://www.example.com/songs/mp3.mp3', 'mp3.mp3')
    
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千与千寻千般痛.
4楼-- · 2018-12-31 02:16

You can get the progress feedback with urlretrieve as well:

def report(blocknr, blocksize, size):
    current = blocknr*blocksize
    sys.stdout.write("\r{0:.2f}%".format(100.0*current/size))

def downloadFile(url):
    print "\n",url
    fname = url.split('/')[-1]
    print fname
    urllib.urlretrieve(url, fname, report)
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只靠听说
5楼-- · 2018-12-31 02:19

In 2012, use the python requests library

>>> import requests
>>> 
>>> url = "http://download.thinkbroadband.com/10MB.zip"
>>> r = requests.get(url)
>>> print len(r.content)
10485760

You can run pip install requests to get it.

Requests has many advantages over the alternatives because the API is much simpler. This is especially true if you have to do authentication. urllib and urllib2 are pretty unintuitive and painful in this case.


2015-12-30

People have expressed admiration for the progress bar. It's cool, sure. There are several off-the-shelf solutions now, including tqdm:

from tqdm import tqdm
import requests

url = "http://download.thinkbroadband.com/10MB.zip"
response = requests.get(url, stream=True)

with open("10MB", "wb") as handle:
    for data in tqdm(response.iter_content()):
        handle.write(data)

This is essentially the implementation @kvance described 30 months ago.

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几人难应
6楼-- · 2018-12-31 02:19

You can use PycURL on Python 2 and 3.

import pycurl

FILE_DEST = 'pycurl.html'
FILE_SRC = 'http://pycurl.io/'

with open(FILE_DEST, 'wb') as f:
    c = pycurl.Curl()
    c.setopt(c.URL, FILE_SRC)
    c.setopt(c.WRITEDATA, f)
    c.perform()
    c.close()
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弹指情弦暗扣
7楼-- · 2018-12-31 02:22

An improved version of the PabloG code for Python 2/3:

#!/usr/bin/env python
# -*- coding: utf-8 -*-
from __future__ import ( division, absolute_import, print_function, unicode_literals )

import sys, os, tempfile, logging

if sys.version_info >= (3,):
    import urllib.request as urllib2
    import urllib.parse as urlparse
else:
    import urllib2
    import urlparse

def download_file(url, dest=None):
    """ 
    Download and save a file specified by url to dest directory,
    """
    u = urllib2.urlopen(url)

    scheme, netloc, path, query, fragment = urlparse.urlsplit(url)
    filename = os.path.basename(path)
    if not filename:
        filename = 'downloaded.file'
    if dest:
        filename = os.path.join(dest, filename)

    with open(filename, 'wb') as f:
        meta = u.info()
        meta_func = meta.getheaders if hasattr(meta, 'getheaders') else meta.get_all
        meta_length = meta_func("Content-Length")
        file_size = None
        if meta_length:
            file_size = int(meta_length[0])
        print("Downloading: {0} Bytes: {1}".format(url, file_size))

        file_size_dl = 0
        block_sz = 8192
        while True:
            buffer = u.read(block_sz)
            if not buffer:
                break

            file_size_dl += len(buffer)
            f.write(buffer)

            status = "{0:16}".format(file_size_dl)
            if file_size:
                status += "   [{0:6.2f}%]".format(file_size_dl * 100 / file_size)
            status += chr(13)
            print(status, end="")
        print()

    return filename

if __name__ == "__main__":  # Only run if this file is called directly
    print("Testing with 10MB download")
    url = "http://download.thinkbroadband.com/10MB.zip"
    filename = download_file(url)
    print(filename)
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