ironic-lib/ironic_lib/metrics_utils.py
Aline Bousquet fb46000e24 Add support for metrics
This patch adds metrics to ironic-lib, so that it can be used by both
Ironic and IPA. It implements a generic MetricLogger including timers,
counters, and gauges with their respective decorators and context
managers. Two default MetricLogger are included: NoopMetricLogger and
StatsdMetricLogger.

Change-Id: I8a62414e6c03acb6f3457f1b8f81c03a9d3a8576
Co-Authored-By: Josh Gachnang <josh@pcsforeducation.com>
Co-Authored-By: Jim Rollenhagen <jim@jimrollenhagen.com>
Co-Authored-By: Alex Weeks <alex.weeks@gmail.com>
Partial-Bug: #1526219
2016-06-28 13:38:01 +01:00

101 lines
3.6 KiB
Python

# Copyright 2016 Rackspace Hosting
# 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.
from oslo_config import cfg
import six
from ironic_lib.common.i18n import _
from ironic_lib import exception
from ironic_lib import metrics
from ironic_lib import metrics_statsd
metrics_opts = [
cfg.StrOpt('backend',
default='noop',
choices=['noop', 'statsd'],
help='Backend to use for the metrics system.'),
cfg.BoolOpt('prepend_host',
default=False,
help='Prepend the hostname to all metric names. '
'The format of metric names is '
'[global_prefix.][host_name.]prefix.metric_name.'),
cfg.BoolOpt('prepend_host_reverse',
default=True,
help='Split the prepended host value by "." and reverse it '
'(to better match the reverse hierarchical form of '
'domain names).'),
cfg.StrOpt('global_prefix',
help='Prefix all metric names with this value. '
'By default, there is no global prefix. '
'The format of metric names is '
'[global_prefix.][host_name.]prefix.metric_name.')
]
CONF = cfg.CONF
CONF.register_opts(metrics_opts, group='metrics')
def get_metrics_logger(prefix='', backend=None, host=None, delimiter='.'):
"""Return a metric logger with the specified prefix.
The format of the prefix is:
[global_prefix<delim>][host_name<delim>]prefix
where <delim> is the delimiter (default is '.')
:param prefix: Prefix for this metric logger.
Value should be a string or None.
:param backend: Backend to use for the metrics system.
Possible values are 'noop' and 'statsd'.
:param host: Name of this node.
:param delimiter: Delimiter to use for the metrics name.
:return: The new MetricLogger.
"""
if not isinstance(prefix, six.string_types):
msg = (_("This metric prefix (%s) is of unsupported type. "
"Value should be a string or None")
% str(prefix))
raise exception.InvalidMetricConfig(msg)
if CONF.metrics.prepend_host and host:
if CONF.metrics.prepend_host_reverse:
host = '.'.join(reversed(host.split('.')))
if prefix:
prefix = delimiter.join([host, prefix])
else:
prefix = host
if CONF.metrics.global_prefix:
if prefix:
prefix = delimiter.join([CONF.metrics.global_prefix, prefix])
else:
prefix = CONF.metrics.global_prefix
backend = backend or CONF.metrics.backend
if backend == 'statsd':
return metrics_statsd.StatsdMetricLogger(prefix, delimiter=delimiter)
elif backend == 'noop':
return metrics.NoopMetricLogger(prefix, delimiter=delimiter)
else:
msg = (_("The backend is set to an unsupported type: "
"%s. Value should be 'noop' or 'statsd'.")
% backend)
raise exception.InvalidMetricConfig(msg)
def list_opts():
"""Entry point for oslo-config-generator."""
return [('metrics', metrics_opts)]