Welcome to Statsd Metrics’s documentation!¶
Contents:
Metrics¶
Define the data types used in Statsd. Each data type is defined as a class, supported data types are:
Note
The metric classes and helper functions are available from the package
directly, but internally they are defined in metrics
module.
So there is no need to import the metrics
module direcly,
unless you’re trying to access those objects that are not used reguraly and hence
are not exported, like the AbstractMetric
class.
Each metric requires a name and a value.
from statsdmetrics import Counter, Timer
counter = Counter('event.login', 1)
timer = Timer('db.query.user', 10)
An optional sample rate can be specified for the metrics. Sample rate is used by the client and the server to help to reduce network traffic, or reduce the load on the server.
>>> from statsdmetrics import Counter
>>> counter = Counter('event.login', 1, 0.2)
>>> counter.name
'event.login'
>>> counter.count
1
>>> counter.sample_rate
0.2
All metrics have name
and sample_rate
properties,
but they store their value in different properties.
Metrics provide to_request()
method to create the proper value used to send the metric to the server.
>>> from statsdmetrics import Counter, Timer, Gauge, Set, GaugeDelta
>>> counter = Counter('event.login', 1, 0.2)
>>> counter.to_request()
'event.login:1|c|@0.2'
>>> timer = Timer('db.query.user', 10, 0.5)
>>> timer.to_request()
'db.query.user:10|ms|@0.5'
>>> gauge = Gauge('memory', 20480)
>>> gauge.to_request()
'memory:20480|g'
>>> set_ = Set('unique.users', 'first')
>>> set_.to_request()
'unique.users:first|s'
>>> delta = GaugeDelta('memory', 128)
>>> delta.to_request()
'memory:+128|g'
>>> delta.delta = -256
>>> delta.to_request()
'memory:-256|g'
metrics
– Metric classes and helper functions¶
Metric Classes¶
-
class
metrics.
AbstractMetric
¶ Abstract class that all metric classes would extend from
-
name
¶ the name of the metric
-
sample_rate
¶ the rate of sampling that the client considers when sending metrics
-
to_request
() → str¶ return the string that is used in the Statsd request to send the metric
-
-
class
metrics.
Counter
(name, count[, sample_rate])¶ A metric to count events
-
count
¶ current count of events being reporeted via the metric
-
-
class
metrics.
Timer
(name, milliseconds[, sample_rate])¶ A metric for timing durations, in milliseconds.
-
milliseconds
¶ number of milliseconds for the duration
-
-
class
metrics.
Gauge
(name, value[, sample_rate])¶ Any arbitrary value, like the memory usage in bytes.
-
value
¶ the value of the metric
-
Module functions¶
-
metrics.
normalize_metric_name
(name) → str¶ normalize a metric name, removing characters that might not be welcome by common backends.
>>> from statsdmetrics import normalize_metric_name >>> normalize_metric_name("will replace some, and $remove! others*") 'will_replace_some_and_remove_others'
If passed argument is not a string, an
TypeError
is raised.
-
metrics.
parse_metric_from_request
(request) → str¶ parse a metric object from a request string.
>>> from statsdmetrics import parse_metric_from_request >>> metric = parse_metric_from_request("memory:2048|g") >>> type(metric) <class 'statsdmetrics.metrics.Gauge'> >>> metric.name, metric.value, metric.sample_rate ('memory', 2048.0, 1) >>> metric = parse_metric_from_request('event.connections:-2|c|@0.6') >>> type(metric) <class 'statsdmetrics.metrics.Counter'> >>> metric.name, metric.count, metric.sample_rate ('event.connections', -2, 0.6)
If the request is invalid, a
ValueError
is raised.
Client¶
To send the metrics to Statsd server, client classes are available
in the client
package and client.tcp
module.
client
– Statsd client¶
-
class
client.
Client
(host[, port=8125][, prefix=''])¶ Default Statsd client that sends each metric in a separate UDP request
-
host
¶ the host name (or IP address) of Statsd server. This property is readonly.
-
port
¶ the port number of Statsd server. This property is readonly.
-
prefix
¶ the default prefix for all metric names sent from the client
-
remote_address
¶ tuple of resolved server address (host, port). This property is readonly.
-
increment
(name[, count=1][, rate=1])¶ Increase a
Counter
metric bycount
with an integer value. An optional sample rate can be specified.
-
decrement
(name[, count=1][, rate=1])¶ Decrease a
Counter
metric bycount
with an integer value. An optional sample rate can be specified.
-
timing
(name, milliseconds[, rate=1])¶ Send a
Timer
metric for the duration of a task in milliseconds. Themilliseconds
should be a none-negative numeric value. An optional sample rate can be specified.
-
gauge
(name, value[, rate=1])¶ Send a
Gauge
metric with the specified value. Thevalue
should be a none-negative numeric value. An optional sample rate can be specified.
-
set
(name, value[, rate=1])¶ Send a
Set
metric with the specified value. The server will count the number of unique values during each sampling period. Thevalue
could be any value that can be converted to a string. An optional sample rate can be specified.
-
gauge_delta
(name, delta[, rate=1])¶ Send a
GaugeDelta
metric with the specified delta. Thedelta
should be a numeric value. An optional sample rate can be specified.
-
batch_client
([size=512])¶ Create a
BatchClient
object, using the same configurations of current client. This batch client could be used as a context manager in awith
statement. After thewith
block when the context manager exits, all the metrics are flushed to the server in batch requests.
-
Note
Most Statsd servers do not apply the sample rate on timing metrics calculated results (mean, percentile, max, min), gauge or set metrics, but they take the rate into account for the number of received samples. Some statsd servers totally ignore the sample rate for metrics other than counters.
Examples¶
from statsdmetrics.client import Client
client = Client("stats.example.org")
client.increment("login")
client.timing("db.search.username", 3500)
client.prefix = "other"
client.gauge_delta("memory", -256)
client.decrement(name="connections", count=2)
from statsdmetrics.client import Client
client = Client("stats.example.org")
with client.batch_client() as batch_client:
batch_client.increment("login")
batch_client.decrement(name="connections", count=2)
batch_client.timing("db.search.username", 3500)
# now all metrics are flushed automatically in batch requests
-
class
client.
BatchClient
(host[, port=8125][, prefix=''][, batch_size=512])¶ Statsd client that buffers all metrics and sends them in batch requests over UDP when instructed to flush the metrics explicitly.
Each UDP request might contain multiple metrics, but limited to a certain batch size to avoid UDP fragmentation.
The size of batch requests is not the fixed size of the requests, since metrics can not be broken into multiple requests. So if adding a new metric overflows this size, then that metric will be sent in a new batch request.
-
batch_size
¶ Size of each batch request. This property is readonly.
-
clear
()¶ Clear buffered metrics
-
flush
()¶ Send the buffered metrics in batch requests.
-
from statsdmetrics.client import BatchClient
client = BatchClient("stats.example.org")
client.set("unique.ip_address", "10.10.10.1")
client.gauge("memory", 20480)
client.flush() # sends one UDP packet to remote server, carrying both metrics
client.tcp
– Statsd client sending metrics over TCP¶
-
class
client.tcp.
TCPClient
(host[, port=8125][, prefix=''])¶ Statsd client that sends each metric in separate requests over TCP.
Provides the same interface as
Client
.
Examples¶
from statsdmetrics.client.tcp import TCPClient
client = TCPClient("stats.example.org")
client.increment("login")
client.timing("db.search.username", 3500)
client.prefix = "other"
client.gauge_delta("memory", -256)
client.decrement(name="connections", count=2)
from statsdmetrics.client.tcp import TCPClient
client = TCPClient("stats.example.org")
with client.batch_client() as batch_client:
batch_client.increment("login")
batch_client.decrement(name="connections", count=2)
batch_client.timing("db.search.username", 3500)
# now all metrics are flushed automatically in batch requests
-
class
client.tcp.
TCPBatchClient
(host[, port=8125][, prefix=''][, batch_size=512])¶ Statsd client that buffers all metrics and sends them in batch requests over TCP when instructed to flush the metrics explicitly.
Provides the same interface as
BatchClient
.
from statsdmetrics.client.tcp import TCPBatchClient
client = TCPBatchClient("stats.example.org")
client.set("unique.ip_address", "10.10.10.1")
client.gauge("memory", 20480)
client.flush() # sends one TCP packet to remote server, carrying both metrics
Introduction¶
Statsd metrics is an API to create, parse or send metrics to a Statsd server.
Metric Classes¶
Metric classes are used to define the data type and values for each metric, and to create the contents of the request that will be setn to the Statsd server.
Available metrics:
The metrics
module also provides helper functions to normalize metric names, and a parse a Statsd request
and return the corresponding metric object. This could be used on the server side to parse the received requests.
Clients¶
Client
: Default client, sends request on each call using UDPBatchClient
: Buffers metrics and flushes them in batch requests using UDPTCPClient
: Sends request on each call using TCPTCPBatchClient
: Buffers metrics and flushes them in batch requests using TCP
Installation¶
pip install statsdmetrics
Dependencies¶
There are no specific dependencies, it runs on Python 2.7+ (CPython 2.7, 3.2, 3.3 3.4 and 3.5, PyPy 2.6 and PyPy3 2.4, and Jython 2.7 are tested)
However on development (and test) environment mock is required, and distutilazy (or setuptools as a fallback) is used to run the tests.
# on dev/test env
pip install -r requirements-dev.txt
License¶
Statsd metrics is released under the terms of the MIT license.
Development¶
- Code is on GitHub
- Documentations are on Read The Docs