Cleanup exceptions

The exceptions were not appropriate for a library.

Closes-Bug: 1469832
Change-Id: I823d9cddd63080654d51b6f9d04f0e7c2b657fc1

oslo_cache/_memcache_pool.py

@@ -120,7 +120,7 @@ class ConnectionPool(queue.Queue):
         try:
             conn = self.get(timeout=self._connection_get_timeout)
         except queue.Empty:
-            raise exception.UnexpectedError(
+            raise exception.QueueEmpty(
                 _('Unable to get a connection from pool id %(id)s after '
                   '%(seconds)s seconds.') %
                 {'id': id(self), 'seconds': self._connection_get_timeout})

oslo_cache/backends/mongo.py

@@ -229,17 +229,17 @@ class MongoApi(object):
         self.hosts = arguments.pop('db_hosts', None)
         if self.hosts is None:
             msg = _('db_hosts value is required')
-            raise exception.ValidationError(message=msg)
+            raise exception.ConfigurationError(msg)
 
         self.db_name = arguments.pop('db_name', None)
         if self.db_name is None:
             msg = _('database db_name is required')
-            raise exception.ValidationError(message=msg)
+            raise exception.ConfigurationError(msg)
 
         self.cache_collection = arguments.pop('cache_collection', None)
         if self.cache_collection is None:
             msg = _('cache_collection name is required')
-            raise exception.ValidationError(message=msg)
+            raise exception.ConfigurationError(msg)
 
         self.username = arguments.pop('username', None)
         self.password = arguments.pop('password', None)
@@ -250,7 +250,7 @@ class MongoApi(object):
             self.w = int(self.w)
         except ValueError:
             msg = _('integer value expected for w (write concern attribute)')
-            raise exception.ValidationError(message=msg)
+            raise exception.ConfigurationError(msg)
 
         self.read_preference = arguments.pop('read_preference', None)
 
@@ -258,7 +258,7 @@ class MongoApi(object):
         if self.use_replica:
             if arguments.get('replicaset_name') is None:
                 msg = _('replicaset_name required when use_replica is True')
-                raise exception.ValidationError(message=msg)
+                raise exception.ConfigurationError(msg)
             self.replicaset_name = arguments.get('replicaset_name')
 
         self.son_manipulator = arguments.pop('son_manipulator', None)
@@ -273,7 +273,7 @@ class MongoApi(object):
             self.ttl_seconds = int(self.ttl_seconds)
         except ValueError:
             msg = _('integer value expected for mongo_ttl_seconds')
-            raise exception.ValidationError(message=msg)
+            raise exception.ConfigurationError(msg)
 
         self.conn_kwargs['ssl'] = arguments.pop('ssl', False)
         if self.conn_kwargs['ssl']:
@@ -298,7 +298,7 @@ class MongoApi(object):
         try:
             import ssl
         except ImportError:
-            raise exception.ValidationError(_('no ssl support available'))
+            raise exception.ConfigurationError(_('no ssl support available'))
         req_type = req_type.upper()
         try:
             return {
@@ -309,7 +309,7 @@ class MongoApi(object):
         except KeyError:
             msg = _('Invalid ssl_cert_reqs value of %s, must be one of '
                     '"NONE", "OPTIONAL", "REQUIRED"') % (req_type)
-            raise exception.ValidationError(message=msg)
+            raise exception.ConfigurationError(msg)
 
     def _get_db(self):
         # defer imports until backend is used
@@ -498,7 +498,7 @@ class AbstractManipulator(object):
         :returns: transformed SON object
 
         """
-        raise exception.NotImplemented()  # pragma: no cover
+        raise NotImplementedError()  # pragma: no cover
 
     @abc.abstractmethod
     def transform_outgoing(self, son, collection):
@@ -509,7 +509,7 @@ class AbstractManipulator(object):
 
         :returns: transformed SON object
         """
-        raise exception.NotImplemented()  # pragma: no cover
+        raise NotImplementedError()  # pragma: no cover
 
     def will_copy(self):
         """Will this SON manipulator make a copy of the incoming document?

oslo_cache/core.py

@@ -129,11 +129,11 @@ def configure_cache_region(region):
 
     :param region: optional CacheRegion object, if not provided a new region
                    will be instantiated
-    :raises: exception.ValidationError
+    :raises: exception.ConfigurationError
     :returns: dogpile.cache.CacheRegion
     """
     if not isinstance(region, dogpile.cache.CacheRegion):
-        raise exception.ValidationError(
+        raise exception.ConfigurationError(
             _('region not type dogpile.cache.CacheRegion'))
 
     if not region.is_configured:

oslo_cache/exception.py

@@ -12,88 +12,10 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-import logging as log
 
-from oslo_config import cfg
+class ConfigurationError(Exception):
-from oslo_utils import encodeutils
+    """Raised when the cache isn't configured correctly."""
-import six
-
-from oslo_cache._i18n import _, _LW
 
 
-CONF = cfg.CONF
+class QueueEmpty(Exception):
-LOG = log.getLogger(__name__)
+    """Raised when a connection cannot be acquired."""
-
-# Tests use this to make exception message format errors fatal
-_FATAL_EXCEPTION_FORMAT_ERRORS = False
-
-
-class Error(Exception):
-    """Base error class.
-
-    Child classes should define an HTTP status code, title, and a
-    message_format.
-
-    """
-    code = None
-    title = None
-    message_format = None
-
-    def __init__(self, message=None, **kwargs):
-        try:
-            message = self._build_message(message, **kwargs)
-        except KeyError:
-            # if you see this warning in your logs, please raise a bug report
-            if _FATAL_EXCEPTION_FORMAT_ERRORS:
-                raise
-            else:
-                LOG.warning(_LW('missing exception kwargs (programmer error)'))
-                message = self.message_format
-
-        super(Error, self).__init__(message)
-
-    def _build_message(self, message, **kwargs):
-        """Builds and returns an exception message.
-
-        :raises: KeyError given insufficient kwargs
-
-        """
-        if not message:
-            try:
-                message = self.message_format % kwargs
-            except UnicodeDecodeError:
-                try:
-                    kwargs = {k: encodeutils.safe_decode(v)
-                              for k, v in six.iteritems(kwargs)}
-                except UnicodeDecodeError:
-                    # NOTE(jamielennox): This is the complete failure case
-                    # at least by showing the template we have some idea
-                    # of where the error is coming from
-                    message = self.message_format
-                else:
-                    message = self.message_format % kwargs
-
-        return message
-
-
-class ValidationError(Error):
-    message_format = _("Expecting to find %(attribute)s in %(target)s -"
-                       " the server could not comply with the request"
-                       " since it is either malformed or otherwise"
-                       " incorrect. The client is assumed to be in error.")
-    code = 400
-    title = 'Bad Request'
-
-
-class NotImplemented(Error):
-    message_format = _("The action you have requested has not"
-                       " been implemented.")
-    code = 501
-    title = 'Not Implemented'
-
-
-class UnexpectedError(Error):
-    message_format = _("An unexpected error prevented the server from "
-                       "fulfilling your request.")
-    code = 500
-    title = 'Internal Server Error'

oslo_cache/tests/test_cache.py

@@ -318,7 +318,7 @@ class CacheRegionTest(BaseTestCase):
             self.assertEqual(NO_VALUE, value)
 
     def test_configure_non_region_object_raises_error(self):
-        self.assertRaises(exception.ValidationError,
+        self.assertRaises(exception.ConfigurationError,
                           cache.configure_cache_region,
                           "bogus")
 

oslo_cache/tests/test_cache_backend_mongo.py

@@ -297,28 +297,28 @@ class MongoCache(test_cache.BaseTestCase):
     def test_missing_db_hosts(self):
         self.arguments.pop('db_hosts')
         region = dp_region.make_region()
-        self.assertRaises(exception.ValidationError, region.configure,
+        self.assertRaises(exception.ConfigurationError, region.configure,
                           'oslo_cache.mongo',
                           arguments=self.arguments)
 
     def test_missing_db_name(self):
         self.arguments.pop('db_name')
         region = dp_region.make_region()
-        self.assertRaises(exception.ValidationError, region.configure,
+        self.assertRaises(exception.ConfigurationError, region.configure,
                           'oslo_cache.mongo',
                           arguments=self.arguments)
 
     def test_missing_cache_collection_name(self):
         self.arguments.pop('cache_collection')
         region = dp_region.make_region()
-        self.assertRaises(exception.ValidationError, region.configure,
+        self.assertRaises(exception.ConfigurationError, region.configure,
                           'oslo_cache.mongo',
                           arguments=self.arguments)
 
     def test_incorrect_write_concern(self):
         self.arguments['w'] = 'one value'
         region = dp_region.make_region()
-        self.assertRaises(exception.ValidationError, region.configure,
+        self.assertRaises(exception.ConfigurationError, region.configure,
                           'oslo_cache.mongo',
                           arguments=self.arguments)
 
@@ -363,7 +363,7 @@ class MongoCache(test_cache.BaseTestCase):
     def test_missing_replica_set_name(self):
         self.arguments['use_replica'] = True
         region = dp_region.make_region()
-        self.assertRaises(exception.ValidationError, region.configure,
+        self.assertRaises(exception.ConfigurationError, region.configure,
                           'oslo_cache.mongo',
                           arguments=self.arguments)
 
@@ -377,7 +377,7 @@ class MongoCache(test_cache.BaseTestCase):
     def test_incorrect_mongo_ttl_seconds(self):
         self.arguments['mongo_ttl_seconds'] = 'sixty'
         region = dp_region.make_region()
-        self.assertRaises(exception.ValidationError, region.configure,
+        self.assertRaises(exception.ConfigurationError, region.configure,
                           'oslo_cache.mongo',
                           arguments=self.arguments)
 

oslo_cache/tests/test_connection_pool.py

@@ -125,7 +125,7 @@ class TestConnectionPool(test_cache.BaseTestCase):
         # Make sure we've consumed the only available connection from the pool
         conn = connection_pool.get_nowait()
 
-        self.assertRaises(exception.UnexpectedError, _acquire_connection)
+        self.assertRaises(exception.QueueEmpty, _acquire_connection)
 
         # Put the connection back and ensure we can acquire the connection
         # after it is available.