Merge "Update compute vnic pollster to use cache"

ceilometer/compute/pollsters.py

@@ -348,11 +348,26 @@ class NetPollster(plugin.ComputePollster):
                 'network.outgoing.bytes',
                 'network.outgoing.packets']
 
+    CACHE_KEY_VNIC = 'vnics'
+
+    def _get_vnics_for_instance(self, cache, inspector, instance_name):
+        i_cache = cache.setdefault(self.CACHE_KEY_VNIC, {})
+        if instance_name not in i_cache:
+            i_cache[instance_name] = list(
+                inspector.inspect_vnics(instance_name)
+            )
+        return i_cache[instance_name]
+
     def get_counters(self, manager, cache, instance):
         instance_name = _instance_name(instance)
         self.LOG.info('checking instance %s', instance.id)
         try:
-            for vnic, info in manager.inspector.inspect_vnics(instance_name):
+            vnics = self._get_vnics_for_instance(
+                cache,
+                manager.inspector,
+                instance_name,
+            )
+            for vnic, info in vnics:
                 self.LOG.info(self.NET_USAGE_MESSAGE, instance_name,
                               vnic.name, info.rx_bytes, info.tx_bytes)
                 yield self.make_vnic_counter(instance,

tests/compute/test_pollsters.py

@@ -295,6 +295,34 @@ class TestNetPollster(TestPollsterBase):
         _verify_vnic_metering('network.outgoing.packets', '192.168.0.4', 12L,
                               "%s-%s" % (instance_name_id, vnic2.name))
 
+    @mock.patch('ceilometer.pipeline.setup_pipeline', mock.MagicMock())
+    def test_get_counters_cache(self):
+        vnic0 = virt_inspector.Interface(
+            name='vnet0',
+            fref='fa163e71ec6e',
+            mac='fa:16:3e:71:ec:6d',
+            parameters=dict(ip='10.0.0.2',
+                            projmask='255.255.255.0',
+                            projnet='proj1',
+                            dhcp_server='10.0.0.1'))
+        stats0 = virt_inspector.InterfaceStats(rx_bytes=1L, rx_packets=2L,
+                                               tx_bytes=3L, tx_packets=4L)
+        vnics = [(vnic0, stats0)]
+
+        self.mox.ReplayAll()
+
+        mgr = manager.AgentManager()
+        pollster = pollsters.NetPollster()
+        cache = {
+            pollster.CACHE_KEY_VNIC: {
+                self.instance.name: vnics,
+            },
+        }
+        counters = list(pollster.get_counters(mgr, cache, self.instance))
+        assert counters
+        # We should have one of each counter for one vnic
+        self.assertEqual(len(counters), 4)
+
 
 class TestCPUPollster(TestPollsterBase):