Use json instead of jsonutils in rpc.impl_fake.

The fake rpc backend uses json just to make sure the data that was
passed in can be serialized.  Our jsonutils module makes this check a
no-op, because it will automatically convert the data we pass in as
primitive types if needed.  Change this module back to using the json
module directly and add a comment about why we don't use jsonutils here.

Also add a test that ensures that non-primitive types raise an exception
in the fake rpc driver.

Change-Id: I61f46242cb98c875a94d86283e30efb24cc580ad

2 files changed, 21 insertions, 2 deletions

diff --git a/openstack/common/rpc/impl_fake.py b/openstack/common/rpc/impl_fake.py
index ff16208..59f6fb3 100644
--- a/openstack/common/rpc/impl_fake.py
+++ b/openstack/common/rpc/impl_fake.py
@@ -18,11 +18,15 @@ queues.  Casts will block, but this is very useful for tests.
 """
 
 import inspect
+# NOTE(russellb): We specifically want to use json, not our own jsonutils.
+# jsonutils has some extra logic to automatically convert objects to primitive
+# types so that they can be serialized.  We want to catch all cases where
+# non-primitive types make it into this code and treat it as an error.
+import json
 import time
 
 import eventlet
 
-from openstack.common import jsonutils
 from openstack.common.rpc import common as rpc_common
 
 CONSUMERS = {}
@@ -121,7 +125,7 @@ def create_connection(conf, new=True):
 
 def check_serialize(msg):
     """Make sure a message intended for rpc can be serialized."""
-    jsonutils.dumps(msg)
+    json.dumps(msg)
 
 
 def multicall(conf, context, topic, msg, timeout=None):
@@ -154,6 +158,7 @@ def call(conf, context, topic, msg, timeout=None):
 
 
 def cast(conf, context, topic, msg):
+    check_serialize(msg)
     try:
         call(conf, context, topic, msg)
     except Exception:
diff --git a/tests/unit/rpc/test_fake.py b/tests/unit/rpc/test_fake.py
index 8ceac47..b3079d6 100644
--- a/tests/unit/rpc/test_fake.py
+++ b/tests/unit/rpc/test_fake.py
@@ -22,11 +22,25 @@ Unit Tests for remote procedure calls using fake_impl
 import eventlet
 eventlet.monkey_patch()
 
+from openstack.common import cfg
+from openstack.common import rpc
 from openstack.common.rpc import impl_fake
 from tests.unit.rpc import common
 
 
+CONF = cfg.CONF
+
+
 class RpcFakeTestCase(common.BaseRpcTestCase):
     def setUp(self):
         self.rpc = impl_fake
         super(RpcFakeTestCase, self).setUp()
+
+    def test_non_primitive_raises(self):
+        class Foo(object):
+            pass
+
+        self.assertRaises(TypeError, self.rpc.cast, CONF, self.context,
+                          'foo', {'x': Foo()})
+        self.assertRaises(TypeError, self.rpc.call, CONF, self.context,
+                          'foo', {'x': Foo()})