Support different publisher interval

Changes the agent manager to poll based on pipeline configuration, to
support different interval requirement from different publishers.

This patch clean up the test case for agent managers. It makes the changes
a bit bigger, however, it's not so easy to seprate this cleanup patch
with different interval part.

For bp publisher-counters-frequency

Change-Id: I3c1163e37de6a17261d2c570843845696ebff58f
Signed-off-by: Yunhong, Jiang <yunhong.jiang@intel.com>

1 files changed, 55 insertions, 17 deletions

diff --git a/ceilometer/agent.py b/ceilometer/agent.py
index b631b3e9..faf3c372 100644
--- a/ceilometer/agent.py
+++ b/ceilometer/agent.py
@@ -16,15 +16,38 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+import abc
+import itertools
+
 from oslo.config import cfg
 from stevedore import dispatch
-
+from ceilometer.openstack.common import context
 from ceilometer.openstack.common import log
 from ceilometer import pipeline
 
 LOG = log.getLogger(__name__)
 
 
+class PollingTask(object):
+    """Polling task for polling counters and inject into pipeline
+    A polling task can be invoked periodically or only once"""
+
+    def __init__(self, agent_manager):
+        self.manager = agent_manager
+        self.pollsters = set()
+        self.publish_context = pipeline.PublishContext(
+            agent_manager.context,
+            cfg.CONF.counter_source)
+
+    def add(self, pollster, pipelines):
+        self.publish_context.add_pipelines(pipelines)
+        self.pollsters.update([pollster])
+
+    @abc.abstractmethod
+    def poll_and_publish(self):
+        """Polling counter and publish into pipeline."""
+
+
 class AgentManager(object):
 
     def __init__(self, extension_manager):
@@ -38,19 +61,34 @@ class AgentManager(object):
 
         self.pollster_manager = extension_manager
 
-    def publish_counters_from_one_pollster(self, ext, manager, context,
-                                           *args, **kwargs):
-        """Used to invoke the plugins loaded by the ExtensionManager.
-        """
-        try:
-            publisher = manager.pipeline_manager.publisher(
-                context,
-                cfg.CONF.counter_source,
-            )
-            with publisher as p:
-                LOG.debug('Polling and publishing %s', ext.name)
-                p(ext.obj.get_counters(manager, *args, **kwargs))
-        except Exception as err:
-            LOG.warning('Continuing after error from %s: %s',
-                        ext.name, err)
-            LOG.exception(err)
+        self.context = context.RequestContext('admin', 'admin', is_admin=True)
+
+    @abc.abstractmethod
+    def create_polling_task(self):
+        """Create an empty polling task"""
+
+    def setup_polling_tasks(self):
+        polling_tasks = {}
+        for pipeline, pollster in itertools.product(
+                self.pipeline_manager.pipelines,
+                self.pollster_manager.extensions):
+            for counter in pollster.obj.get_counter_names():
+                if pipeline.support_counter(counter):
+                    polling_task = polling_tasks.get(pipeline.interval, None)
+                    if not polling_task:
+                        polling_task = self.create_polling_task()
+                        polling_tasks[pipeline.interval] = polling_task
+                    polling_task.add(pollster, [pipeline])
+                    break
+
+        return polling_tasks
+
+    def initialize_service_hook(self, service):
+        self.service = service
+        for interval, task in self.setup_polling_tasks().iteritems():
+            self.service.tg.add_timer(interval,
+                                      self.interval_task,
+                                      task=task)
+
+    def interval_task(self, task):
+        task.poll_and_publish()