aodh/ceilometer/plugin.py
Julien Danjou 59b5a5a488 Allow to publish several counters in a row
Support publishing of multiple counters at once. This change the pipeline
and RPC calls to send a list of counter by default instead of only once
counter. This allows to make only one RPC calls when sending multiple
counters to be more efficient.

This implements blueprint publish-counters-list-rpc

Change-Id: Ie4155b35585f261e6ff9816e5a845a479151eefd
Signed-off-by: Julien Danjou <julien@danjou.info>
2013-02-11 12:23:23 +01:00

134 lines
3.9 KiB
Python

# -*- encoding: utf-8 -*-
#
# Copyright © 2012 New Dream Network, LLC (DreamHost)
#
# Author: Doug Hellmann <doug.hellmann@dreamhost.com>
#
# 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.
"""Base class for plugins.
"""
import abc
from collections import namedtuple
from ceilometer.openstack.common import cfg
# Import rabbit_notifier to register notification_topics flag so that
# plugins can use it
import ceilometer.openstack.common.notifier.rabbit_notifier
ExchangeTopics = namedtuple('ExchangeTopics', ['exchange', 'topics'])
class PluginBase(object):
"""Base class for all plugins.
"""
def is_enabled(self):
"""Return boolean indicating whether this plugin should
be enabled and used by the caller.
"""
return True
class NotificationBase(PluginBase):
"""Base class for plugins that support the notification API."""
__metaclass__ = abc.ABCMeta
def is_enabled(self):
return True
@abc.abstractmethod
def get_event_types(self):
"""Return a sequence of strings defining the event types to be
given to this plugin."""
@abc.abstractmethod
def get_exchange_topics(self, conf):
"""Return a sequence of ExchangeTopics defining the exchange and
topics to be connected for this plugin."""
@abc.abstractmethod
def process_notification(self, message):
"""Return a sequence of Counter instances for the given message."""
def notification_to_metadata(self, event):
"""Transform a payload dict to a metadata dict."""
metadata = dict([(k, event['payload'].get(k))
for k in self.metadata_keys])
metadata['event_type'] = event['event_type']
metadata['host'] = event['publisher_id']
return metadata
class PollsterBase(PluginBase):
"""Base class for plugins that support the polling API."""
__metaclass__ = abc.ABCMeta
@staticmethod
@abc.abstractmethod
def get_counter_names():
"""Return a sequence of Counter names supported by the pollster."""
@abc.abstractmethod
def get_counters(self, manager, instance):
"""Return a sequence of Counter instances from polling the
resources."""
class PublisherBase(PluginBase):
"""Base class for plugins that publish the sampler."""
__metaclass__ = abc.ABCMeta
@abc.abstractmethod
def publish_counters(self, context, counters, source):
"Publish counters into final conduit"
class TransformerBase(PluginBase):
"""Base class for plugins that transform the counter."""
__metaclass__ = abc.ABCMeta
@abc.abstractmethod
def handle_sample(self, context, counter, source):
"""Transform a counter
parameter:
context: Passed from the data collector
counters: An interator of counters.
source: Passed from data collector.
"""
def flush(self, context, source):
"""Flush counters cached previously"""
return []
def __init__(self, **parameter):
"""Setup transformer
Each time a transformed is involved in a pipeline, a new transformer
instance is created and chained into the pipeline. i.e. transformer
instance is per pipeline. This helps if transformer need keep some
cache and per-pipeline information.
parameter:
kwds: the parameter that is defined in pipeline config file
"""
super(TransformerBase, self).__init__()