+ @staticmethod
+ def _sign_url(url, sig_key, sig_secret, life=600, include_qs=False):
+ flags = '10' if include_qs else '00'
+ expiration_date = '%x' % (int(time.time()) + life)
+
+ def str_to_hex(str):
+ return binascii.b2a_hex(str.encode('ascii')).decode('ascii')
+
+ def hex_to_str(hex):
+ return binascii.a2b_hex(hex)
+
+ relative_path = url.split('http://link.theplatform.com/s/')[1].split('?')[0]
+ clear_text = hex_to_str(flags + expiration_date + str_to_hex(relative_path))
+ checksum = hmac.new(sig_key.encode('ascii'), clear_text, hashlib.sha1).hexdigest()
+ sig = flags + expiration_date + checksum + str_to_hex(sig_secret)
+ return '%s&sig=%s' % (url, sig)
+