oauth.py

#! /usr/bin/python
# -*- coding: utf-8 -*-

# (The MIT License)
#
# Copyright © 2009 John Tantalo
#
# Permission is hereby granted, free of charge, to any person obtaining a copy of
# this software and associated documentation files (the ‘Software’), to deal in
# the Software without restriction, including without limitation the rights to
# use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
# the Software, and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED ‘AS IS’, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
# FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
# COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
# IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

from random import getrandbits
from time import time
from urllib import quote, urlencode
import hmac
from hashlib import sha1


def escape(s):
  return quote(str(s), safe='~')

def hmac_sha1_base64(key, value):
  """Base-64 encoded HMAC SHA1 hash."""
  return hmac.new(key, value, sha1).digest().encode('base64')[:-1]

def signed_url(url, oauth_consumer_secret, oauth_token_secret,
               method="GET", **kwargs):
  """The signed URL with the given arguments and method."""
  return '%s?%s' % (url, signed_args(url, oauth_consumer_secret,
                                     oauth_token_secret, method, **kwargs))

def sig_key(oauth_consumer_secret, oauth_token_secret):
  """The signature key."""
  return '&'.join([escape(oauth_consumer_secret), escape(oauth_token_secret)])

def sig_base(url, method="GET", **kwargs):
  """The signature base."""
  params = ['%s=%s' % (escape(k), escape(kwargs[k])) for k in sorted(kwargs)]
  return '&'.join(map(escape, (method.upper(), url, '&'.join(params))))

def signed_args(url, oauth_consumer_secret, oauth_token_secret,
                method="GET", **kwargs):
  """The signed arguments for the given URL and method."""
  # start with defaults
  args = dict(
    oauth_version='1.0',
    oauth_signature_method='HMAC-SHA1',
    oauth_timestamp=int(time()),
    oauth_nonce=getrandbits(64),
  )
  # add overrides
  args.update(kwargs)
  # build key from secrets
  key = sig_key(oauth_consumer_secret, oauth_token_secret)
  # build base from arguments
  base = sig_base(url, method, **args)
  # compute signature digest from key and signature base
  args['oauth_signature'] = hmac_sha1_base64(key, base)
  # sort and encode args
  return urlencode([(k, args[k]) for k in sorted(args)])

oauth.test.py

#! /usr/bin/python
# -*- coding: utf-8 -*-
 
# (The MIT License)
#
# Copyright © 2009 John Tantalo
#
# Permission is hereby granted, free of charge, to any person obtaining a copy of
# this software and associated documentation files (the ‘Software’), to deal in
# the Software without restriction, including without limitation the rights to
# use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
# the Software, and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED ‘AS IS’, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
# FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
# COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
# IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

from oauth import signed_url
import unittest


class TestOAuth(unittest.TestCase):
  def test_oauth(self):
    """The canonical test from http://oauth.net/core/1.0"""
    url = signed_url(
      url="http://photos.example.net/photos",
      method="GET",
      oauth_consumer_key="dpf43f3p2l4k3l03",
      oauth_consumer_secret="kd94hf93k423kf44",
      oauth_token="nnch734d00sl2jdk",
      oauth_token_secret="pfkkdhi9sl3r4s00",
      oauth_signature_method="HMAC-SHA1",
      oauth_timestamp="1191242096",
      oauth_nonce="kllo9940pd9333jh",
      oauth_version="1.0",
      file="vacation.jpg",
      size="original")
    expected_url =\
      "http://photos.example.net/photos?file=vacation.jpg&"\
      "oauth_consumer_key=dpf43f3p2l4k3l03&oauth_nonce=kllo9940pd9333jh&"\
      "oauth_signature=tR3%2BTy81lMeYAr%2FFid0kMTYa%2FWM%3D&"\
      "oauth_signature_method=HMAC-SHA1&oauth_timestamp=1191242096&"\
      "oauth_token=nnch734d00sl2jdk&oauth_version=1.0&size=original"
    self.assertEqual(url, expected_url)


if __name__ == "__main__":
  unittest.main()