Source code for ceilometer.api.hooks
#
# Copyright 2012 New Dream Network, LLC (DreamHost)
#
# 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 oslo_config import cfg
from oslo_log import log
import oslo_messaging
from pecan import hooks
from ceilometer.i18n import _LE
from ceilometer import messaging
from ceilometer import storage
LOG = log.getLogger(__name__)
cfg.CONF.import_opt('telemetry_driver', 'ceilometer.publisher.messaging',
group='publisher_notifier')
[docs]class ConfigHook(hooks.PecanHook):
"""Attach the configuration object to the request.
That allows controllers to get it.
"""
@staticmethod
[docs] def before(state):
state.request.cfg = cfg.CONF
[docs]class DBHook(hooks.PecanHook):
def __init__(self):
self.storage_connection = DBHook.get_connection('metering')
self.event_storage_connection = DBHook.get_connection('event')
if (not self.storage_connection
and not self.event_storage_connection):
raise Exception("Api failed to start. Failed to connect to "
"databases, purpose: %s" %
', '.join(['metering', 'event']))
[docs] def before(self, state):
state.request.storage_conn = self.storage_connection
state.request.event_storage_conn = self.event_storage_connection
@staticmethod
[docs] def get_connection(purpose):
try:
return storage.get_connection_from_config(cfg.CONF, purpose)
except Exception as err:
params = {"purpose": purpose, "err": err}
LOG.exception(_LE("Failed to connect to db, purpose %(purpose)s "
"retry later: %(err)s") % params)
[docs]class NotifierHook(hooks.PecanHook):
"""Create and attach a notifier to the request.
Usually, samples will be push to notification bus by notifier when they
are posted via /v2/meters/ API.
"""
def __init__(self):
transport = messaging.get_transport()
self.notifier = oslo_messaging.Notifier(
transport, driver=cfg.CONF.publisher_notifier.telemetry_driver,
publisher_id="ceilometer.api")
[docs] def before(self, state):
state.request.notifier = self.notifier
[docs]class TranslationHook(hooks.PecanHook):
[docs] def after(self, state):
# After a request has been done, we need to see if
# ClientSideError has added an error onto the response.
# If it has we need to get it info the thread-safe WSGI
# environ to be used by the ParsableErrorMiddleware.
if hasattr(state.response, 'translatable_error'):
state.request.environ['translatable_error'] = (
state.response.translatable_error)