From 3be95adcebfef6e862eda2827a216048b4e9007a Mon Sep 17 00:00:00 2001 From: Assaf Muller Date: Wed, 11 Mar 2015 21:39:54 -0400 Subject: [PATCH] Add support for multiple namespaces in Targets In order for projects to use the namespace property of Targets in a backwards compatible way (To support rolling upgrades), a Target may now belong to more than a single namespace (i.e. 'namespace1' and None). This way, if the server is upgraded first, the version that introduces namespaces to a project will place the server RPC methods in ['some_namespace', None]. Pre-upgrade agents will send messages in the null namespace while post-upgrade agents will send messages in 'some_namespace', and both will be accepted. Change-Id: I713fe9228111c36aa3f7fb95cbd59c99100e8c96 Closes-Bug: #1430984 --- oslo_messaging/rpc/dispatcher.py | 2 +- oslo_messaging/target.py | 9 ++++++++- oslo_messaging/tests/rpc/test_dispatcher.py | 12 ++++++++++++ 3 files changed, 21 insertions(+), 2 deletions(-) diff --git a/oslo_messaging/rpc/dispatcher.py b/oslo_messaging/rpc/dispatcher.py index d4a882310..8879f352d 100644 --- a/oslo_messaging/rpc/dispatcher.py +++ b/oslo_messaging/rpc/dispatcher.py @@ -111,7 +111,7 @@ class RPCDispatcher(object): @staticmethod def _is_namespace(target, namespace): - return namespace == target.namespace + return namespace in target.accepted_namespaces @staticmethod def _is_compatible(target, version): diff --git a/oslo_messaging/target.py b/oslo_messaging/target.py index f37a2b296..e91cc878a 100644 --- a/oslo_messaging/target.py +++ b/oslo_messaging/target.py @@ -57,16 +57,23 @@ class Target(object): servers listening on a topic by setting fanout to ``True``, rather than just one of them. :type fanout: bool + :param legacy_namespaces: A server always accepts messages specified via + the 'namespace' parameter, and may also accept messages defined via + this parameter. This option should be used to switch namespaces safely + during rolling upgrades. + :type legacy_namespaces: list of strings """ def __init__(self, exchange=None, topic=None, namespace=None, - version=None, server=None, fanout=None): + version=None, server=None, fanout=None, + legacy_namespaces=None): self.exchange = exchange self.topic = topic self.namespace = namespace self.version = version self.server = server self.fanout = fanout + self.accepted_namespaces = [namespace] + (legacy_namespaces or []) def __call__(self, **kwargs): for a in ('exchange', 'topic', 'namespace', diff --git a/oslo_messaging/tests/rpc/test_dispatcher.py b/oslo_messaging/tests/rpc/test_dispatcher.py index edc4e7e0a..32e0b09c5 100644 --- a/oslo_messaging/tests/rpc/test_dispatcher.py +++ b/oslo_messaging/tests/rpc/test_dispatcher.py @@ -89,6 +89,18 @@ class TestDispatcher(test_utils.BaseTestCase): dispatch_to=None, ctxt={}, msg=dict(method='foo', version='3.2'), success=False, ex=oslo_messaging.UnsupportedVersion)), + ('message_in_null_namespace_with_multiple_namespaces', + dict(endpoints=[dict(namespace='testns', + legacy_namespaces=[None])], + dispatch_to=dict(endpoint=0, method='foo'), + ctxt={}, msg=dict(method='foo', namespace=None), + success=True, ex=None)), + ('message_in_wrong_namespace_with_multiple_namespaces', + dict(endpoints=[dict(namespace='testns', + legacy_namespaces=['second', None])], + dispatch_to=None, + ctxt={}, msg=dict(method='foo', namespace='wrong'), + success=False, ex=oslo_messaging.UnsupportedVersion)), ] def test_dispatcher(self):