how to python mimetypes.guess_type from a file-like object

Question

>>> mimetypes.guess_type('picture.jpg')
('image/jpeg', None)

Now I have a file-like object, (eg. stingIO), which content is image's data

How can i detect the mimetypes from a file-like object

Answer 1

The python mimetype standard module maps filenames to mime-types and vice versa. To use it, you'll need a filename or a mime-type, in which case it'll give you back a possible file extension.

It won't/doesn't determine the mime-type based on a file's contents. You need another type of tool to do that. Libmagic, the library behind the unix file command, is one of those tools. The filemagic module (https://pypi.python.org/pypi/filemagic/1.6) is a python interface to libmagic.

import urllib2
import magic

img_data = urllib2.urlopen('https://www.google.com/images/srpr/logo11w.png').read()
# You can add flags 
# magic.Magic(flags=magic.MAGIC_MIME_TYPE) for take "/image/png"
m = magic.Magic()
print m.id_buffer(img_data)
m.close()