Reuse module `exceptions` from Oslo

The exception module in oslo common code and in keystoneclient are similar.
In case of unification openstack clients, we should use modules from Oslo.

Changes of this patch:
- imported exceptions from common code instead of `apiclient.exception`
- added aliases for exceptions which was renamed
(reason: backwards compatibility)
- moved exceptions `EmptyCatalog` from `apiclient.exception` to `exceptions`
- cleaned `apiclient.exception` from duplicated exceptions
- `apiclient.__init__` and `apiclient.exceptions` are kept and labeled as
'deprecated'(reason: backwards compatibility)

bp common-client-library-2

Change-Id: Iedf4e5d753d4278d81751ba0f55fdef3566b56de

1 files changed, 12 insertions, 8 deletions

diff --git a/keystoneclient/exceptions.py b/keystoneclient/exceptions.py
index c462074..c688fac 100644
--- a/keystoneclient/exceptions.py
+++ b/keystoneclient/exceptions.py
@@ -17,7 +17,14 @@ Exception definitions.
 """
 
 #flake8: noqa
-from keystoneclient.apiclient.exceptions import *
+from keystoneclient.openstack.common.apiclient.exceptions import *
+
+# NOTE(akurilin): This alias should be left here to support backwards
+# compatibility until we are sure that usage of these exceptions in
+# projects is correct.
+ConnectionError = ConnectionRefused
+HTTPNotImplemented = HttpNotImplemented
+Timeout = RequestTimeout
 
 
 class CertificateConfigError(Exception):
@@ -29,18 +36,15 @@ class CertificateConfigError(Exception):
         super(CertificateConfigError, self).__init__(msg)
 
 
-class ConnectionError(ClientException):
-    """Something went wrong trying to connect to a server"""
+class EmptyCatalog(EndpointNotFound):
+    """The service catalog is empty."""
+    pass
 
 
-class SSLError(ConnectionError):
+class SSLError(ConnectionRefused):
     """An SSL error occurred."""
 
 
-class Timeout(ClientException):
-    """The request timed out."""
-
-
 class DiscoveryFailure(ClientException):
     """Discovery of client versions failed."""