Python HTTP - Post a Binary File using urllib2

作者：半瓶墨水链接：http://www.2maomao.com/blog/python-http-post-a-binary-file-using-urllib2/

I was trying to post a png file to our internal webserver for some quick and dirty task, but Python keep throwing ascii encoding exception.

Then I search “post http binary urllib2″ and did found several options, like multipart/form-data and pycurl, but they need the webserver’s help to accomplish a simple file posting.

In the end I decide to dig into Python’s httplib and urllib2 to find out what’s going on, if that doesn’t work I will fallback to raw TCP socket solution.

Luckily I got the following solution that works like a charm:
1. set Content-Length header(of the file) before doing post
2. pass a opened file when doing post

Sample code:

Python语言: Python Post a Binary File using urllib2

importurllib2,os
 image_path = "png\\01.png"
 url = 'http://xx.oo.com/webserviceapi/postfile/'
 length = os.path.getsize(image_path)
 png_data = open(image_path, "rb")
 request = urllib2.Request(url, data=png_data)
 request.add_header('Cache-Control', 'no-cache')
 request.add_header('Content-Length', '%d' % length)
 request.add_header('Content-Type', 'image/png')
 res = urllib2.urlopen(request).read().strip()
 return res