canny.py

import binascii
import hashlib
import json

from Crypto.Cipher import AES

from django.conf import settings

from pinecast.helpers import gravatar

def get_canny_token(req):
    if not req.user:
        return None

    user_data = {
        'avatarURL': gravatar(req.user.email),
        'email': req.user.email,
        'id': req.user.id,
        'name': req.user.email,
    }
    plaintext = json.dumps(user_data)

    dig = hashlib.md5(settings.CANNY_SSO_KEY.encode('utf-8')).digest()

    def pad_input(input):
        block_size = 16
        if (len(input) % block_size == 0):
          return input
        padding_required = block_size - (len(input) % block_size)
        return input.encode('utf-8') + padding_required * bytes([padding_required])

    cipher = AES.new(dig, AES.MODE_ECB)
    encrypted = binascii.hexlify(bytearray(cipher.encrypt(pad_input(plaintext)))).decode('utf-8')
    return encrypted