diff options
Diffstat (limited to 'oslo/db/sqlalchemy/session.py')
| -rw-r--r-- | oslo/db/sqlalchemy/session.py | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/oslo/db/sqlalchemy/session.py b/oslo/db/sqlalchemy/session.py index 192ad1d..882a9ea 100644 --- a/oslo/db/sqlalchemy/session.py +++ b/oslo/db/sqlalchemy/session.py @@ -293,6 +293,7 @@ from sqlalchemy.sql.expression import select from oslo.db._i18n import _LW from oslo.db import exception from oslo.db import options +from oslo.db.sqlalchemy import compat from oslo.db.sqlalchemy import exc_filters from oslo.db.sqlalchemy import utils @@ -311,12 +312,22 @@ def _thread_yield(dbapi_con, con_record): time.sleep(0) -def _begin_ping_listener(connection): - """Ping the server at transaction begin. +def _connect_ping_listener(connection, branch): + """Ping the server at connection startup. Ping the server at transaction begin and transparently reconnect if a disconnect exception occurs. """ + if branch: + return + + # turn off "close with result". This can also be accomplished + # by branching the connection, however just setting the flag is + # more performant and also doesn't get involved with some + # connection-invalidation awkardness that occurs (see + # https://bitbucket.org/zzzeek/sqlalchemy/issue/3215/) + save_should_close_with_result = connection.should_close_with_result + connection.should_close_with_result = False try: # run a SELECT 1. use a core select() so that # any details like that needed by Oracle, DB2 etc. are handled. @@ -329,6 +340,8 @@ def _begin_ping_listener(connection): # new connections assuming they are good now. # run the select again to re-validate the Connection. connection.scalar(select([1])) + finally: + connection.should_close_with_result = save_should_close_with_result def _setup_logging(connection_debug=0): @@ -389,8 +402,8 @@ def create_engine(sql_connection, sqlite_fk=False, mysql_sql_mode=None, # register alternate exception handler exc_filters.register_engine(engine) - # register on begin handler - sqlalchemy.event.listen(engine, "begin", _begin_ping_listener) + # register engine connect handler + compat.engine_connect(engine, _connect_ping_listener) # initial connect + test _test_connection(engine, max_retries, retry_interval) |