Merge "Add _wrap_db_error support for postgresql"

2 files changed, 131 insertions, 1 deletions

diff --git a/oslo/db/sqlalchemy/session.py b/oslo/db/sqlalchemy/session.py
index 31d1fd0..94c0911 100644
--- a/oslo/db/sqlalchemy/session.py
+++ b/oslo/db/sqlalchemy/session.py
@@ -403,8 +403,12 @@ def _raise_if_duplicate_entry_error(integrity_error, engine_name):
 # mysql:
 # (OperationalError) (1213, 'Deadlock found when trying to get lock; try '
 #                     'restarting transaction') <query_str> <query_args>
+#
+# postgresql:
+# (TransactionRollbackError) deadlock detected <deadlock_details>
 _DEADLOCK_RE_DB = {
-    "mysql": re.compile(r"^.*\(1213, 'Deadlock.*")
+    "mysql": re.compile(r"^.*\(1213, 'Deadlock.*"),
+    "postgresql": re.compile(r"^.*deadlock detected.*")
 }
 
 
@@ -457,6 +461,22 @@ def _wrap_db_error(f):
             # unique constraint, from error message.
             _raise_if_duplicate_entry_error(e, self.bind.dialect.name)
             raise exception.DBError(e)
+        except sqla_exc.DBAPIError as e:
+            # NOTE(wingwj): This branch is used to catch deadlock exception
+            # under postgresql. The original exception thrown from postgresql
+            # is TransactionRollbackError, it's not included in the sqlalchemy.
+            # Moreover, DBAPIError is the base class of OperationalError
+            # and IntegrityError, so we catch it on the end of the process.
+            #
+            # The issue has also submitted to sqlalchemy on
+            # https://bitbucket.org/zzzeek/sqlalchemy/issue/3075/
+            # support-non-standard-dbapi-exception
+            # (FIXME) This branch should be refactored after the patch
+            # merged in & our requirement of sqlalchemy updated
+            _raise_if_db_connection_lost(e, self.bind)
+            _raise_if_deadlock_error(e, self.bind.dialect.name)
+            LOG.exception(_LE('DBAPIError exception wrapped from %s') % e)
+            raise exception.DBError(e)
         except Exception as e:
             LOG.exception(_LE('DB exception wrapped.'))
             raise exception.DBError(e)
diff --git a/tests/sqlalchemy/test_sqlalchemy.py b/tests/sqlalchemy/test_sqlalchemy.py
index 2036e13..2c8017f 100644
--- a/tests/sqlalchemy/test_sqlalchemy.py
+++ b/tests/sqlalchemy/test_sqlalchemy.py
@@ -260,6 +260,116 @@ class TestDBDisconnected(oslo_test.BaseTestCase):
                 self._test_ping_listener_disconnected(connection)
 
 
+class TestDBDeadlocked(test_base.DbTestCase):
+
+    def test_mysql_deadlock(self):
+        statement = ('SELECT quota_usages.created_at AS '
+                     'quota_usages_created_at, quota_usages.updated_at AS '
+                     'quota_usages_updated_at, quota_usages.deleted_at AS '
+                     'quota_usages_deleted_at, quota_usages.deleted AS '
+                     'quota_usages_deleted, quota_usages.id AS '
+                     'quota_usages_id, quota_usages.project_id AS '
+                     'quota_usages_project_id, quota_usages.user_id AS '
+                     'quota_usages_user_id, quota_usages.resource AS '
+                     'quota_usages_resource, quota_usages.in_use AS '
+                     'quota_usages_in_use, quota_usages.reserved AS '
+                     'quota_usages_reserved, quota_usages.until_refresh AS '
+                     'quota_usages_until_refresh \nFROM quota_usages \n'
+                     'WHERE quota_usages.deleted = %(deleted_1)s AND '
+                     'quota_usages.project_id = %(project_id_1)s AND '
+                     '(quota_usages.user_id = %(user_id_1)s OR '
+                     'quota_usages.user_id IS NULL) FOR UPDATE')
+        params = {'project_id_1': u'8891d4478bbf48ad992f050cdf55e9b5',
+                  'user_id_1': u'22b6a9fe91b349639ce39146274a25ba',
+                  'deleted_1': 0}
+        orig = sqla_exc.SQLAlchemyError("(1213, 'Deadlock found when trying "
+                                        "to get lock; try restarting "
+                                        "transaction')")
+        deadlock_error = sqla_exc.OperationalError(statement, params, orig)
+        self.assertRaises(db_exc.DBDeadlock,
+                          session._raise_if_deadlock_error,
+                          deadlock_error,
+                          'mysql')
+
+    def test_postgresql_deadlock(self):
+        statement = ('SELECT quota_usages.created_at AS '
+                     'quota_usages_created_at, quota_usages.updated_at AS '
+                     'quota_usages_updated_at, quota_usages.deleted_at AS '
+                     'quota_usages_deleted_at, quota_usages.deleted AS '
+                     'quota_usages_deleted, quota_usages.id AS '
+                     'quota_usages_id, quota_usages.project_id AS '
+                     'quota_usages_project_id, quota_usages.user_id AS '
+                     'quota_usages_user_id, quota_usages.resource AS '
+                     'quota_usages_resource, quota_usages.in_use AS '
+                     'quota_usages_in_use, quota_usages.reserved AS '
+                     'quota_usages_reserved, quota_usages.until_refresh AS '
+                     'quota_usages_until_refresh \nFROM quota_usages \n'
+                     'WHERE quota_usages.deleted = %(deleted_1)s AND '
+                     'quota_usages.project_id = %(project_id_1)s AND '
+                     '(quota_usages.user_id = %(user_id_1)s OR '
+                     'quota_usages.user_id IS NULL) FOR UPDATE')
+        params = {'project_id_1': u'8891d4478bbf48ad992f050cdf55e9b5',
+                  'user_id_1': u'22b6a9fe91b349639ce39146274a25ba',
+                  'deleted_1': 0}
+        orig = sqla_exc.SQLAlchemyError("(TransactionRollbackError) "
+                                        "deadlock detected")
+        deadlock_error = sqla_exc.DBAPIError(statement, params, orig)
+        self.assertRaises(db_exc.DBDeadlock,
+                          session._raise_if_deadlock_error,
+                          deadlock_error,
+                          'postgresql')
+
+    def test_mysql_fail_without_deadlock(self):
+        statement = ('SELECT quota_usages.created_at AS '
+                     'quota_usages_created_at, quota_usages.updated_at AS '
+                     'quota_usages_updated_at, quota_usages.deleted_at AS '
+                     'quota_usages_deleted_at, quota_usages.deleted AS '
+                     'quota_usages_deleted, quota_usages.id AS '
+                     'quota_usages_id, quota_usages.project_id AS '
+                     'quota_usages_project_id, quota_usages.user_id AS '
+                     'quota_usages_user_id, quota_usages.resource AS '
+                     'quota_usages_resource, quota_usages.in_use AS '
+                     'quota_usages_in_use, quota_usages.reserved AS '
+                     'quota_usages_reserved, quota_usages.until_refresh AS '
+                     'quota_usages_until_refresh \nFROM quota_usages \n'
+                     'WHERE quota_usages.deleted = %(deleted_1)s AND '
+                     'quota_usages.project_id = %(project_id_1)s AND '
+                     '(quota_usages.user_id = %(user_id_1)s OR '
+                     'quota_usages.user_id IS NULL) FOR UPDATE')
+        params = {'project_id_1': u'8891d4478bbf48ad992f050cdf55e9b5',
+                  'user_id_1': u'22b6a9fe91b349639ce39146274a25ba',
+                  'deleted_1': 0}
+        orig = sqla_exc.SQLAlchemyError('Other error occurred.')
+        dbapi_error = sqla_exc.DBAPIError(statement, params, orig)
+        self.assertIsNone(session._raise_if_deadlock_error(dbapi_error,
+                                                           'mysql'))
+
+    def test_postgresql_fail_without_deadlock(self):
+        statement = ('SELECT quota_usages.created_at AS '
+                     'quota_usages_created_at, quota_usages.updated_at AS '
+                     'quota_usages_updated_at, quota_usages.deleted_at AS '
+                     'quota_usages_deleted_at, quota_usages.deleted AS '
+                     'quota_usages_deleted, quota_usages.id AS '
+                     'quota_usages_id, quota_usages.project_id AS '
+                     'quota_usages_project_id, quota_usages.user_id AS '
+                     'quota_usages_user_id, quota_usages.resource AS '
+                     'quota_usages_resource, quota_usages.in_use AS '
+                     'quota_usages_in_use, quota_usages.reserved AS '
+                     'quota_usages_reserved, quota_usages.until_refresh AS '
+                     'quota_usages_until_refresh \nFROM quota_usages \n'
+                     'WHERE quota_usages.deleted = %(deleted_1)s AND '
+                     'quota_usages.project_id = %(project_id_1)s AND '
+                     '(quota_usages.user_id = %(user_id_1)s OR '
+                     'quota_usages.user_id IS NULL) FOR UPDATE')
+        params = {'project_id_1': u'8891d4478bbf48ad992f050cdf55e9b5',
+                  'user_id_1': u'22b6a9fe91b349639ce39146274a25ba',
+                  'deleted_1': 0}
+        orig = sqla_exc.SQLAlchemyError('Other error occurred.')
+        dbapi_error = sqla_exc.DBAPIError(statement, params, orig)
+        self.assertIsNone(session._raise_if_deadlock_error(dbapi_error,
+                                                           'postgresql'))
+
+
 class MySQLModeTestCase(test_base.MySQLOpportunisticTestCase):
 
     def __init__(self, *args, **kwargs):