diff options
| -rw-r--r-- | oslo_db/api.py | 28 | ||||
| -rw-r--r-- | oslo_db/exception.py | 9 | ||||
| -rw-r--r-- | oslo_db/tests/old_import_api/test_api.py | 21 | ||||
| -rw-r--r-- | oslo_db/tests/test_api.py | 21 |
4 files changed, 75 insertions, 4 deletions
diff --git a/oslo_db/api.py b/oslo_db/api.py index dc71d96..98e4d75 100644 --- a/oslo_db/api.py +++ b/oslo_db/api.py @@ -24,6 +24,7 @@ API methods. """ import logging +import sys import threading import time @@ -69,6 +70,16 @@ def retry_on_deadlock(f): return f +def retry_on_request(f): + """Retry a DB API call if RetryRequest exception was received. + + wrap_db_entry will be applied to all db.api functions marked with this + decorator. + """ + f.enable_retry_on_request = True + return f + + class wrap_db_retry(object): """Retry db.api methods, if db_error raised @@ -91,8 +102,9 @@ class wrap_db_retry(object): :type max_retry_interval: int """ - def __init__(self, retry_interval, max_retries, inc_retry_interval, - max_retry_interval, retry_on_disconnect, retry_on_deadlock): + def __init__(self, retry_interval=0, max_retries=0, inc_retry_interval=0, + max_retry_interval=0, retry_on_disconnect=False, + retry_on_deadlock=False, retry_on_request=False): super(wrap_db_retry, self).__init__() self.db_error = () @@ -100,6 +112,8 @@ class wrap_db_retry(object): self.db_error += (exception.DBConnectionError, ) if retry_on_deadlock: self.db_error += (exception.DBDeadlock, ) + if retry_on_request: + self.db_error += (exception.RetryRequest, ) self.retry_interval = retry_interval self.max_retries = max_retries self.inc_retry_interval = inc_retry_interval @@ -118,6 +132,10 @@ class wrap_db_retry(object): except db_error as e: if remaining == 0: LOG.exception(_LE('DB exceeded retry limit.')) + if isinstance(e, exception.RetryRequest): + six.reraise(type(e.inner_exc), + e.inner_exc, + sys.exc_info()[2]) raise e if remaining != -1: remaining -= 1 @@ -210,15 +228,17 @@ class DBAPI(object): retry_on_disconnect = self.use_db_reconnect and getattr( attr, 'enable_retry_on_disconnect', False) retry_on_deadlock = getattr(attr, 'enable_retry_on_deadlock', False) + retry_on_request = getattr(attr, 'enable_retry_on_request', False) - if retry_on_disconnect or retry_on_deadlock: + if retry_on_disconnect or retry_on_deadlock or retry_on_request: attr = wrap_db_retry( retry_interval=self.retry_interval, max_retries=self.max_retries, inc_retry_interval=self.inc_retry_interval, max_retry_interval=self.max_retry_interval, retry_on_disconnect=retry_on_disconnect, - retry_on_deadlock=retry_on_deadlock)(attr) + retry_on_deadlock=retry_on_deadlock, + retry_on_request=retry_on_request)(attr) return attr diff --git a/oslo_db/exception.py b/oslo_db/exception.py index 5de7f1e..f950f6a 100644 --- a/oslo_db/exception.py +++ b/oslo_db/exception.py @@ -171,3 +171,12 @@ class BackendNotAvailable(Exception): within a test suite. """ + + +class RetryRequest(Exception): + """Error raised when DB operation needs to be retried. + + That could be intentionally raised by the code without any real DB errors. + """ + def __init__(self, inner_exc): + self.inner_exc = inner_exc diff --git a/oslo_db/tests/old_import_api/test_api.py b/oslo_db/tests/old_import_api/test_api.py index 3664e24..1fe3bf3 100644 --- a/oslo_db/tests/old_import_api/test_api.py +++ b/oslo_db/tests/old_import_api/test_api.py @@ -279,3 +279,24 @@ class DBDeadlockTestCase(DBAPITestCase): self.assertEqual( 0, self.test_db_api.error_counter, 'Counter not decremented, retry logic probably failed.') + + +class DBRetryRequestCase(DBAPITestCase): + def test_retry_wrapper_succeeds(self): + @api.wrap_db_retry(max_retries=10, retry_on_request=True) + def some_method(): + pass + + some_method() + + def test_retry_wrapper_reaches_limit(self): + max_retries = 10 + + @api.wrap_db_retry(max_retries=10, retry_on_request=True) + def some_method(res): + res['result'] += 1 + raise exception.RetryRequest(ValueError()) + + res = {'result': 0} + self.assertRaises(ValueError, some_method, res) + self.assertEqual(max_retries + 1, res['result']) diff --git a/oslo_db/tests/test_api.py b/oslo_db/tests/test_api.py index 171e360..18dc586 100644 --- a/oslo_db/tests/test_api.py +++ b/oslo_db/tests/test_api.py @@ -175,3 +175,24 @@ class DBReconnectTestCase(DBAPITestCase): self.assertNotEqual( 0, self.test_db_api.error_counter, 'Retry did not stop after sql_max_retries iterations.') + + +class DBRetryRequestCase(DBAPITestCase): + def test_retry_wrapper_succeeds(self): + @api.wrap_db_retry(max_retries=10, retry_on_request=True) + def some_method(): + pass + + some_method() + + def test_retry_wrapper_reaches_limit(self): + max_retries = 10 + + @api.wrap_db_retry(max_retries=10, retry_on_request=True) + def some_method(res): + res['result'] += 1 + raise exception.RetryRequest(ValueError()) + + res = {'result': 0} + self.assertRaises(ValueError, some_method, res) + self.assertEqual(max_retries + 1, res['result']) |