Sync nova with oslo DB exception cleanup.

DB exceptions have moved to openstack/common/db/exception module so that
they can be shared with multiple DB implementations.

Deadlock checking was also added to oslo to consolidate with
DuplicateKey checking.  This allows us to clean up our
_retry_on_deadlock decorator in sqlalchemy/api.py

Fixes unrelated pep8 issue with duplicate test in test_compute also.

Change-Id: I7e985b384d1ef345e0d67c919b84b4faff869699

1 files changed, 11 insertions, 26 deletions

diff --git a/nova/db/sqlalchemy/api.py b/nova/db/sqlalchemy/api.py
index 1baa192a3..9efdc47f1 100644
--- a/nova/db/sqlalchemy/api.py
+++ b/nova/db/sqlalchemy/api.py
@@ -30,7 +30,6 @@ import uuid
 from oslo.config import cfg
 from sqlalchemy import and_
 from sqlalchemy import Boolean
-from sqlalchemy import exc as sqla_exc
 from sqlalchemy.exc import IntegrityError
 from sqlalchemy.exc import NoSuchTableError
 from sqlalchemy import Integer
@@ -52,6 +51,7 @@ import nova.context
 from nova import db
 from nova.db.sqlalchemy import models
 from nova import exception
+from nova.openstack.common.db import exception as db_exc
 from nova.openstack.common.db.sqlalchemy import session as db_session
 from nova.openstack.common.db.sqlalchemy import utils as sqlalchemyutils
 from nova.openstack.common import log as logging
@@ -143,30 +143,15 @@ def require_aggregate_exists(f):
 
 def _retry_on_deadlock(f):
     """Decorator to retry a DB API call if Deadlock was received."""
-    def _is_deadlock_exc(dberr_info):
-        deadlock_str = 'Deadlock found when trying to get lock'
-        try:
-            if not isinstance(dberr_info, sqla_exc.OperationalError):
-                return False
-            if deadlock_str in dberr_info.message:
-                LOG.warn(_("Deadlock detected when running "
-                           "'%(func_name)s': Retrying..."),
-                           dict(func_name=f.__name__))
-                return True
-        except Exception:
-            pass
-        return False
-
     @functools.wraps(f)
     def wrapped(*args, **kwargs):
         while True:
             try:
                 return f(*args, **kwargs)
-            except db_session.DBError as db_err:
-                exc_info = sys.exc_info()
-                dberr_info = db_err.inner_exception
-                if not _is_deadlock_exc(dberr_info):
-                    raise exc_info[0], exc_info[1], exc_info[2]
+            except db_exc.DBDeadlock:
+                LOG.warn(_("Deadlock detected when running "
+                           "'%(func_name)s': Retrying..."),
+                           dict(func_name=f.__name__))
                 # Retry!
                 time.sleep(0.5)
                 continue
@@ -1264,7 +1249,7 @@ def virtual_interface_create(context, values):
         vif_ref = models.VirtualInterface()
         vif_ref.update(values)
         vif_ref.save()
-    except db_session.DBError:
+    except db_exc.DBError:
         raise exception.VirtualInterfaceCreateException()
 
     return vif_ref
@@ -2079,7 +2064,7 @@ def network_create_safe(context, values):
     try:
         network_ref.save()
         return network_ref
-    except db_session.DBDuplicateEntry:
+    except db_exc.DBDuplicateEntry:
         raise exception.DuplicateVlan(vlan=values['vlan'])
 
 
@@ -2321,7 +2306,7 @@ def network_update(context, network_id, values):
         network_ref.update(values)
         try:
             network_ref.save(session=session)
-        except db_session.DBDuplicateEntry:
+        except db_exc.DBDuplicateEntry:
             raise exception.DuplicateVlan(vlan=values['vlan'])
         return network_ref
 
@@ -3547,7 +3532,7 @@ def instance_type_create(context, values):
             instance_type_ref.update(values)
             instance_type_ref.save(session=session)
         except Exception, e:
-            raise db_session.DBError(e)
+            raise db_exc.DBError(e)
         return _dict_with_extra_specs(instance_type_ref)
 
 
@@ -4209,7 +4194,7 @@ def s3_image_create(context, image_uuid):
         s3_image_ref.update({'uuid': image_uuid})
         s3_image_ref.save()
     except Exception, e:
-        raise db_session.DBError(e)
+        raise db_exc.DBError(e)
 
     return s3_image_ref
 
@@ -4729,7 +4714,7 @@ def task_log_begin_task(context, task_name, period_beginning, period_ending,
         task.task_items = task_items
     try:
         task.save()
-    except db_session.DBDuplicateEntry:
+    except db_exc.DBDuplicateEntry:
         raise exception.TaskAlreadyRunning(task_name=task_name, host=host)