A summary of how Python implements file downloads

The front-end time encounters a need to download files through a URL, simply write a py script. From the web search for the implementation of the Python file download method, summarized as follows, for reference.

The following methods have been tested, environment win8.1  python2.6/2.7

to be added. --20150507

 

method one:

use   urllib   module provides The Urlretrieve () function. The Urlretrieve () method downloads remote data directly to the local.

Urlretrieve (URL, [Filename=none, [Reporthook=none, [Data=none]])

Description

• The parameter finename specifies that the local path is saved (Urllib generates a temporary file to hold the data if the parameter is not specified.) ）

• parameter Reporthook is a callback function that triggers the callback when the server is connected and the corresponding data block is transferred. We can use this callback function to display the current download progress.

• parameter data refers to a post to the server, the method returns a two-element (filename, headers) tuple, filename represents the path saved to a local, and the header represents the server's response header.  

instance:

#!/usr/bin/python#encoding:utf-8import  Urllibimport osdef schedule (a,b,c):     "    a: Data blocks already downloaded     b: Size of data block     c: Remote file size     ' '      Per = 100.0 * a * b / c    if per >  100 :        per = 100     print  '%.2f%% '  % perurl =  ' http://www.python.org/ftp/python/2.7.5/ python-2.7.5.tar.bz2 ' #local  = url.split ('/') [ -1]local = os.path.join ('/data/software ', ' python-2.7.5.tar.bz2 ') Urllib.urlretrieve (url,local,schedule) ##### #output ###### #0.00% #0.07% #0.13% #0.20%#....# 99.94% #100.00% 

source: http://www.nowamagic.net/ academy/detail/1302861

method two:

Urllib () function using Urlopen

instance:

 

method three:

Use requests module

requests module Download: https:// pypi.python.org/pypi/requests/#downloads

instance:

A summary of how Python implements file downloads