ExStatsD

A statsd client implementation for Elixir.

Usage

Add ExStatsD as a dependency for your application.

defp deps do
  [{:ex_statsd, ">= 0.1.0"}]
end

You should also update your applications list to include statsd:

def application do
  [applications: [:ex_statsd]]
end

Configure ex_statsd using Mix.Config as usual (probably in your config/):

use Mix.Config

config :ex_statsd,
       host: "your.statsd.host.com",
       port: 1234,
       namespace: "your-app"

The defaults are:

host: 127.0.0.1
port: 8125
namespace: nil

The following are the basic metric types. Additional features are described in "Extensions," below.

Counters

Counters can be manipulated with ExStatsD.increment/1 and ExStatsD.decrement/1 for simple counts:

if passed? do
  ExStatsD.increment("cases.passed")
end

if cancelled_account? do
  ExStatsD.decrement("users")
end

You can also provide a sample_rate with ExStatsD.increment/2 and ExStatsD.decrement/2. For example, in this case an increment for cart.added will only be sent 50% of the time:

ExStatsD.increment("cart.added", sample_rate: 0.5)

To set a counter explicitly, use ExStatsD.counter/2:

3 |> ExStatsD.counter("cart.removed")

You can also send a sample_rate:

3 |> ExStatsD.counter("cart.removed", sample_rate: 0.25)

Note that the function returns the value (eg, 3 here), making it suitable for pipelining.

Timers

Manually timed values can be recorded with ExStatsD.timer/2:

elapsed_ms = # something manually timed in
elapsed_ms |> ExStatsD.timer("foobar")

The value passed to ExStatsD.timer/2 (eg, elapsed_ms here) is returned from it, making this suitable for pipelining.

For convenience, you can also time a function call with ExStatsD.timing/2:

ExStatsD.timing "foo.bar", fn ->
  # Time something
end

To sample (ie, 50% of the time), pass a sample_rate:

ExStatsD.timing "foo.bar", fn ->
  # Time something, some of the time
end, sample_rate: 0.5

Note that, regardless of the sample rate, the function is always called -- it's just not always measured. Also note that the return value of the measured function is returned, making this suitable for pipelining.

Sets

A value can be recorded in a set with ExStatsD.set/2:

user_id |> ExStatsD.set("users")

Note that the function returns the value, making it suitable for pipelining.

Extensions

Datadog

Histograms

The histogram extension to StatsD is supported for DogStatsD:

42 |> ExStatsD.histogram("database.query.time", tags: ["db", "perf"])

Note that the function returns the value, making it suitable for pipelining.

License

The MIT License (MIT)

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.