deb-python-kafka/kafka/metrics/metric_name.py
2016-08-02 21:36:00 -07:00

107 lines
3.3 KiB
Python

from __future__ import absolute_import
import copy
class MetricName(object):
"""
This class encapsulates a metric's name, logical group and its
related attributes (tags).
group, tags parameters can be used to create unique metric names.
e.g. domainName:type=group,key1=val1,key2=val2
Usage looks something like this:
# set up metrics:
metric_tags = {'client-id': 'producer-1', 'topic': 'topic'}
metric_config = MetricConfig(tags=metric_tags)
# metrics is the global repository of metrics and sensors
metrics = Metrics(metric_config)
sensor = metrics.sensor('message-sizes')
metric_name = metrics.metric_name('message-size-avg',
'producer-metrics',
'average message size')
sensor.add(metric_name, Avg())
metric_name = metrics.metric_name('message-size-max',
sensor.add(metric_name, Max())
tags = {'client-id': 'my-client', 'topic': 'my-topic'}
metric_name = metrics.metric_name('message-size-min',
'producer-metrics',
'message minimum size', tags)
sensor.add(metric_name, Min())
# as messages are sent we record the sizes
sensor.record(message_size)
"""
def __init__(self, name, group, description=None, tags=None):
"""
Arguments:
name (str): The name of the metric.
group (str): The logical group name of the metrics to which this
metric belongs.
description (str, optional): A human-readable description to
include in the metric.
tags (dict, optional): Additional key/val attributes of the metric.
"""
if not (name and group):
raise Exception('name and group must be non-empty.')
if tags is not None and not isinstance(tags, dict):
raise Exception('tags must be a dict if present.')
self._name = name
self._group = group
self._description = description
self._tags = copy.copy(tags)
self._hash = 0
@property
def name(self):
return self._name
@property
def group(self):
return self._group
@property
def description(self):
return self._description
@property
def tags(self):
return copy.copy(self._tags)
def __hash__(self):
if self._hash != 0:
return self._hash
prime = 31
result = 1
result = prime * result + hash(self.group)
result = prime * result + hash(self.name)
tags_hash = hash(frozenset(self.tags.items())) if self.tags else 0
result = prime * result + tags_hash
self._hash = result
return result
def __eq__(self, other):
if self is other:
return True
if other is None:
return False
return (type(self) == type(other) and
self.group == other.group and
self.name == other.name and
self.tags == other.tags)
def __ne__(self, other):
return not self.__eq__(other)
def __str__(self):
return 'MetricName(name=%s, group=%s, description=%s, tags=%s)' % (
self.name, self.group, self.description, self.tags)