Made algorithm class dependence on hash functions more direct.

- Algorithms now have SHA256, SHA384, and SHA512 static properties that
  refer to the callable that instantiates their hash class
- All algorithms now expect a class (callable) as their hash_alg now.
  This behavior was inconsistent before.

1 files changed, 17 insertions, 11 deletions

diff --git a/jwt/algorithms.py b/jwt/algorithms.py
index d347dcc..d3bc11d 100644
--- a/jwt/algorithms.py
+++ b/jwt/algorithms.py
@@ -23,18 +23,18 @@ def _register_default_algorithms():
     Registers the algorithms that are implemented by the library.
     """
     register_algorithm('none', NoneAlgorithm())
-    register_algorithm('HS256', HMACAlgorithm(hashlib.sha256))
-    register_algorithm('HS384', HMACAlgorithm(hashlib.sha384))
-    register_algorithm('HS512', HMACAlgorithm(hashlib.sha512))
+    register_algorithm('HS256', HMACAlgorithm(HMACAlgorithm.SHA256))
+    register_algorithm('HS384', HMACAlgorithm(HMACAlgorithm.SHA384))
+    register_algorithm('HS512', HMACAlgorithm(HMACAlgorithm.SHA512))
 
     if has_crypto:
-        register_algorithm('RS256', RSAAlgorithm(hashes.SHA256()))
-        register_algorithm('RS384', RSAAlgorithm(hashes.SHA384()))
-        register_algorithm('RS512', RSAAlgorithm(hashes.SHA512()))
+        register_algorithm('RS256', RSAAlgorithm(RSAAlgorithm.SHA256))
+        register_algorithm('RS384', RSAAlgorithm(RSAAlgorithm.SHA384))
+        register_algorithm('RS512', RSAAlgorithm(RSAAlgorithm.SHA512))
 
-        register_algorithm('ES256', ECAlgorithm(hashes.SHA256()))
-        register_algorithm('ES384', ECAlgorithm(hashes.SHA384()))
-        register_algorithm('ES512', ECAlgorithm(hashes.SHA512()))
+        register_algorithm('ES256', ECAlgorithm(ECAlgorithm.SHA256))
+        register_algorithm('ES384', ECAlgorithm(ECAlgorithm.SHA384))
+        register_algorithm('ES512', ECAlgorithm(ECAlgorithm.SHA512))
 
 
 class Algorithm(object):
@@ -86,6 +86,8 @@ class HMACAlgorithm(Algorithm):
     def __init__(self, hash_alg):
         self.hash_alg = hash_alg
 
+    SHA256, SHA384, SHA512 = hashlib.sha256, hashlib.sha384, hashlib.sha512
+
     def prepare_key(self, key):
         if not isinstance(key, string_types) and not isinstance(key, bytes):
             raise TypeError('Expecting a string- or bytes-formatted key.')
@@ -110,7 +112,9 @@ if has_crypto:
         """
 
         def __init__(self, hash_alg):
-            self.hash_alg = hash_alg
+            self.hash_alg = hash_alg()
+
+        SHA256, SHA384, SHA512 = hashes.SHA256, hashes.SHA384, hashes.SHA512
 
         def prepare_key(self, key):
             if isinstance(key, interfaces.RSAPrivateKey) or \
@@ -163,7 +167,9 @@ if has_crypto:
         ECDSA and the specified hash function
         """
         def __init__(self, hash_alg):
-            self.hash_alg = hash_alg
+            self.hash_alg = hash_alg()
+
+        SHA256, SHA384, SHA512 = hashes.SHA256, hashes.SHA384, hashes.SHA512
 
         def prepare_key(self, key):
             if isinstance(key, interfaces.EllipticCurvePrivateKey) or \