Add local node resource for IPMI pollsters

Each pollster should have some resources for polling, but IPMI
pollster is an exception that talk with local IPMI HW directly by
ipmitool. Local node resource is faked resource that stands for
endpoint of localhost. With it, IPMI pollsters can be handled in the
same way as others.

Change-Id: Icda81ffa2334b764e7b508f26efd031f2a863e64

ceilometer/agent/discovery/localnode.py

@@ -0,0 +1,21 @@
+# Copyright 2015 Intel
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+from ceilometer.agent import plugin_base
+
+
+class LocalNodeDiscovery(plugin_base.DiscoveryBase):
+    def discover(self, manager, param=None):
+        """Return local node as resource."""
+        return ['local_host']

ceilometer/ipmi/pollsters/node.py

@@ -36,7 +36,7 @@ class _Base(plugin_base.PollsterBase):
 
     @property
     def default_discovery(self):
-        return None
+        return 'local_node'
 
     @abc.abstractmethod
     def read_data(self):

ceilometer/ipmi/pollsters/sensor.py

@@ -39,7 +39,7 @@ class SensorPollster(plugin_base.PollsterBase):
 
     @property
     def default_discovery(self):
-        return None
+        return 'local_node'
 
     @staticmethod
     def _get_sensor_types(data, sensor_type):

ceilometer/tests/ipmi/pollsters/base.py

@@ -58,7 +58,7 @@ class TestPollsterBase(base.BaseTestCase):
 
     def _verify_metering(self, length, expected_vol=None, node=None):
         cache = {}
-        resources = {}
+        resources = ['local_host']
 
         samples = list(self.pollster.get_samples(self.mgr, cache, resources))
         self.assertEqual(length, len(samples))

setup.cfg

@@ -97,6 +97,7 @@ ceilometer.discover =
     local_instances = ceilometer.compute.discovery:InstanceDiscovery
     endpoint = ceilometer.agent.discovery.endpoint:EndpointDiscovery
     tenant = ceilometer.agent.discovery.tenant:TenantDiscovery
+    local_node = ceilometer.agent.discovery.localnode:LocalNodeDiscovery
     lb_pools = ceilometer.network.services.discovery:LBPoolsDiscovery
     lb_vips = ceilometer.network.services.discovery:LBVipsDiscovery
     lb_members = ceilometer.network.services.discovery:LBMembersDiscovery