# Copyright 2016 Mirantis Inc.
# All Rights Reserved.
#
# 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.
import functools
import signal
import time
from oslo_utils import importutils
from osprofiler.drivers import base
[docs]
class Messaging(base.Driver):
def __init__(self, connection_str, project=None, service=None, host=None,
context=None, conf=None, transport_url=None,
idle_timeout=1, **kwargs):
"""Driver that uses messaging as transport for notifications
:param connection_str: OSProfiler driver connection string,
equals to messaging://
:param project: project name that will be included into notification
:param service: service name that will be included into notification
:param host: host name that will be included into notification
:param context: oslo.messaging context
:param conf: oslo.config CONF object
:param transport_url: oslo.messaging transport, e.g.
rabbit://rabbit:password@devstack:5672/
:param idle_timeout: how long to wait for new notifications after
the last one seen in the trace; this parameter is useful to
collect full trace of asynchronous commands, e.g. when user
runs `osprofiler` right after `openstack server create`
:param kwargs: black hole for any other parameters
"""
self.oslo_messaging = importutils.try_import("oslo_messaging")
if not self.oslo_messaging:
raise ValueError("Oslo.messaging library is required for "
"messaging driver")
super(Messaging, self).__init__(connection_str, project=project,
service=service, host=host)
self.context = context
if not conf:
oslo_config = importutils.try_import("oslo_config")
if not oslo_config:
raise ValueError("Oslo.config library is required for "
"messaging driver")
conf = oslo_config.cfg.CONF
transport_kwargs = {}
if transport_url:
transport_kwargs["url"] = transport_url
self.transport = self.oslo_messaging.get_notification_transport(
conf, **transport_kwargs)
self.client = self.oslo_messaging.Notifier(
self.transport, publisher_id=self.host, driver="messaging",
topics=["profiler"], retry=0)
self.idle_timeout = idle_timeout
[docs]
@classmethod
def get_name(cls):
return "messaging"
[docs]
def notify(self, info, context=None):
"""Send notifications to backend via oslo.messaging notifier API.
:param info: Contains information about trace element.
In payload dict there are always 3 ids:
"base_id" - uuid that is common for all notifications
related to one trace.
"parent_id" - uuid of parent element in trace
"trace_id" - uuid of current element in trace
With parent_id and trace_id it's quite simple to build
tree of trace elements, which simplify analyze of trace.
:param context: request context that is mostly used to specify
current active user and tenant.
"""
info["project"] = self.project
info["service"] = self.service
self.client.info(context or self.context,
"profiler.%s" % info["service"],
info)
[docs]
def get_report(self, base_id):
notification_endpoint = NotifyEndpoint(self.oslo_messaging, base_id)
endpoints = [notification_endpoint]
targets = [self.oslo_messaging.Target(topic="profiler")]
server = self.oslo_messaging.notify.get_notification_listener(
self.transport, targets, endpoints, executor="threading")
state = dict(running=False)
sfn = functools.partial(signal_handler, state=state)
# modify signal handlers to handle interruption gracefully
old_sigterm_handler = signal.signal(signal.SIGTERM, sfn)
old_sigint_handler = signal.signal(signal.SIGINT, sfn)
try:
server.start()
except self.oslo_messaging.server.ServerListenError:
# failed to start the server
raise
except SignalExit:
print("Execution interrupted while trying to connect to "
"messaging server. No data was collected.")
return {}
# connected to server, now read the data
try:
# run until the trace is complete
state["running"] = True
while state["running"]:
last_read_time = notification_endpoint.get_last_read_time()
wait = self.idle_timeout - (time.time() - last_read_time)
if wait < 0:
state["running"] = False
else:
time.sleep(wait)
except SignalExit:
print("Execution interrupted. Terminating")
finally:
server.stop()
server.wait()
# restore original signal handlers
signal.signal(signal.SIGTERM, old_sigterm_handler)
signal.signal(signal.SIGINT, old_sigint_handler)
events = notification_endpoint.get_messages()
if not events:
print("No events are collected for Trace UUID %s. Please note "
"that osprofiler has read ALL events from profiler topic, "
"but has not found any for specified Trace UUID." % base_id)
for n in events:
trace_id = n["trace_id"]
parent_id = n["parent_id"]
name = n["name"]
project = n["project"]
service = n["service"]
host = n["info"]["host"]
timestamp = n["timestamp"]
self._append_results(trace_id, parent_id, name, project, service,
host, timestamp, n)
return self._parse_results()
[docs]
class NotifyEndpoint(object):
def __init__(self, oslo_messaging, base_id):
self.received_messages = []
self.last_read_time = time.time()
self.filter_rule = oslo_messaging.NotificationFilter(
payload={"base_id": base_id})
[docs]
def info(self, ctxt, publisher_id, event_type, payload, metadata):
self.received_messages.append(payload)
self.last_read_time = time.time()
[docs]
def get_messages(self):
return self.received_messages
[docs]
def get_last_read_time(self):
return self.last_read_time # time when the latest event was received
[docs]
class SignalExit(BaseException):
pass
[docs]
def signal_handler(signum, frame, state):
state["running"] = False
raise SignalExit()
