Fixed a couple of anomalies after the last rebase.

Author: mark-adams

jwt/__init__.py

@@ -6,16 +6,14 @@
 """
 
 import binascii
-import sys
 
 from calendar import timegm
 from collections import Mapping
 from datetime import datetime, timedelta
 
 from jwt.utils import base64url_decode, base64url_encode
 
-from .compat import (json, string_types, text_type, constant_time_compare,
-                     timedelta_total_seconds)
+from .compat import (json, string_types, text_type, timedelta_total_seconds)
 
 
 __version__ = '0.4.1'
@@ -53,6 +51,7 @@ def register_algorithm(alg_id, alg_obj):
 from jwt.algorithms import Algorithm, _register_default_algorithms  # NOQA
 _register_default_algorithms()
 
+
 class InvalidTokenError(Exception):
     pass
 

jwt/algorithms.py

@@ -1,13 +1,8 @@
 import hashlib
 import hmac
-import sys
 
 from jwt import register_algorithm
-from jwt.utils import constant_time_compare
-
-if sys.version_info >= (3, 0, 0):
-    unicode = str
-    basestring = str
+from jwt.compat import constant_time_compare, string_types, text_type
 
 try:
     from cryptography.hazmat.primitives import interfaces, hashes
@@ -66,10 +61,10 @@ def __init__(self, hash_alg):
         self.hash_alg = hash_alg
 
     def prepare_key(self, key):
-        if not isinstance(key, basestring) and not isinstance(key, bytes):
+        if not isinstance(key, string_types) and not isinstance(key, text_type):
             raise TypeError('Expecting a string- or bytes-formatted key.')
 
-        if isinstance(key, unicode):
+        if isinstance(key, text_type):
             key = key.encode('utf-8')
 
         return key
@@ -92,7 +87,7 @@ def prepare_key(self, key):
                 return key
 
             if isinstance(key, basestring):
-                if isinstance(key, unicode):
+                if isinstance(key, text_type):
                     key = key.encode('utf-8')
 
                 try:
@@ -140,8 +135,8 @@ def prepare_key(self, key):
                isinstance(key, interfaces.EllipticCurvePublicKey):
                 return key
 
-            if isinstance(key, basestring):
-                if isinstance(key, unicode):
+            if isinstance(key, string_types):
+                if isinstance(key, text_type):
                     key = key.encode('utf-8')
 
                 # Attempt to load key. We don't know if it's

jwt/utils.py

@@ -1,6 +1,4 @@
 import base64
-import hmac
-import sys
 
 
 def base64url_decode(input):
@@ -14,28 +12,3 @@ def base64url_decode(input):
 
 def base64url_encode(input):
     return base64.urlsafe_b64encode(input).replace(b'=', b'')
-
-try:
-    constant_time_compare = hmac.compare_digest
-except AttributeError:
-    # Fallback for Python < 2.7.7 and Python < 3.3
-    def constant_time_compare(val1, val2):
-        """
-        Returns True if the two strings are equal, False otherwise.
-
-        The time taken is independent of the number of characters that match.
-        """
-        if len(val1) != len(val2):
-            return False
-
-        result = 0
-
-        if sys.version_info >= (3, 0, 0):
-            # Bytes are numbers
-            for x, y in zip(val1, val2):
-                result |= x ^ y
-        else:
-            for x, y in zip(val1, val2):
-                result |= ord(x) ^ ord(y)
-
-        return result == 0