rename utils function less like stdlib

Related-Change-Id: I3436bf3724884fe252c6cb603243c1195f67b701
Change-Id: I74199c62b46e4db93a76760ebf91d84e3e1e3cfc

swift/common/middleware/crypto/keymaster.py

@@ -18,7 +18,7 @@ import os
 
 from swift.common.middleware.crypto.crypto_utils import CRYPTO_KEY_CALLBACK
 from swift.common.swob import Request, HTTPException
-from swift.common.utils import readconf, base64decode
+from swift.common.utils import readconf, strict_b64decode
 from swift.common.wsgi import WSGIContext
 
 
@@ -137,8 +137,8 @@ class KeyMaster(object):
             conf = readconf(self.keymaster_config_path, 'keymaster')
         b64_root_secret = conf.get('encryption_root_secret')
         try:
-            binary_root_secret = base64decode(b64_root_secret,
-                                              allow_line_breaks=True)
+            binary_root_secret = strict_b64decode(b64_root_secret,
+                                                  allow_line_breaks=True)
             if len(binary_root_secret) < 32:
                 raise ValueError
             return binary_root_secret

swift/common/utils.py

@@ -4337,7 +4337,7 @@ def safe_json_loads(value):
     return None
 
 
-def base64decode(value, allow_line_breaks=False):
+def strict_b64decode(value, allow_line_breaks=False):
     '''
     Validate and decode Base64-encoded data.
 

test/unit/common/test_utils.py

@@ -38,6 +38,7 @@ import string
 import sys
 import json
 import math
+import inspect
 
 import six
 from six import BytesIO, StringIO
@@ -3889,7 +3890,7 @@ cluster_dfw1 = http://dfw1.host/v1/
             self.fail('Invalid results from pure function:\n%s' %
                       '\n'.join(failures))
 
-    def test_base64decode(self):
+    def test_strict_b64decode(self):
         expectations = {
             None: ValueError,
             0: ValueError,
@@ -3914,19 +3915,23 @@ cluster_dfw1 = http://dfw1.host/v1/
 
         failures = []
         for value, expected in expectations.items():
-            if expected is ValueError:
-                try:
-                    result = utils.base64decode(value)
-                except ValueError:
-                    pass
+            try:
+                result = utils.strict_b64decode(value)
+            except Exception as e:
+                if inspect.isclass(expected) and issubclass(
+                        expected, Exception):
+                    if not isinstance(e, expected):
+                        failures.append('%r raised %r (expected to raise %r)' %
+                                        (value, e, expected))
                 else:
-                    failures.append('%r => %r (expected to raise ValueError)' %
-                                    (value, result))
+                    failures.append('%r raised %r (expected to return %r)' %
+                                    (value, e, expected))
             else:
-                try:
-                    result = utils.base64decode(value)
-                    self.assertEqual(expected, result)
-                except AssertionError:
+                if inspect.isclass(expected) and issubclass(
+                        expected, Exception):
+                    failures.append('%r => %r (expected to raise %r)' %
+                                    (value, result, expected))
+                elif result != expected:
                     failures.append('%r => %r (expected %r)' % (
                         value, result, expected))
         if failures: