cozy_telemetry v0.4.3

View Source CozyTelemetry (cozy_telemetry v0.4.3)

Provides a modular approach for using beam-telemetry packages.

quick-start

 Quick Start

Before running CozyTelemetry, you must provide some modules. For example:

defmodule MyApp.Cache do
  use CozyTelemetry.Metrics
  use CozyTelemetry.Measurements

  # cache related code
  # ...

  @impl CozyTelemetry.Metrics
  def metrics(_meta) do
    [
      summary("cache.duration",
        unit: {:native, :second},
        tags: [:type, :key]
      ),

      last_value("cache.stats.hits",
        event_name: "cache.stats",
        measurement: :hits,
        tags: [:cache]
      )
    ]
  end

  @impl CozyTelemetry.Measurements
  def periodic_measurements(meta) do
    [
      {__MODULE__, :dispatch_stats, []}
    ]
  end
end

Then, set some base configuration within config/config.exs:

config :my_app, CozyTelemetry,
  meta: [],
  metrics: [
    MyApp.Cache
  ],
  measurements: [
    MyApp.Cache
  ],
  reporter: {:console, []},
  poller: [period: 10_000]

Use the application configuration you've already set and include CozyTelemetry.* in the list of supervised children:

# lib/my_app/application.ex
def start(_type, _args) do
  cozy_telemetry_config = Application.fetch_env!(:my_app, CozyTelemetry)

  children = [
    {CozyTelemetry.Reporter, cozy_telemetry_config},
    {CozyTelemetry.Poller, cozy_telemetry_config},
    # ...
  ]

  Supervisor.start_link(children, strategy: :one_for_one, name: MyApp.Supervisor)
end

about-option-meta

 about option :meta

The value of option :meta is a keyword list, which will be passed as the argument of:

See CozyTelemetry.Metrics and CozyTelemetry.Measurements.

about-option-metrics

 about option :metrics

The value of option :metrics is a list of metrics modules.

See CozyTelemetry.Metrics.

about-option-optional_metrics

 about option :optional_metrics

Same as option :metrics, but ignore errors when the given metrics module is missing.

about-option-measurements

 about option :measurements

The value of option :measurements is a list of measurements modules.

See CozyTelemetry.Measurements.

about-option-optional_measurements

 about option :optional_measurements

Same as option :measurements, but ignore errors when the given measurements module is missing.

See CozyTelemetry.Measurements.

When using :cozy_telemetry as a direct dependency, this option is unnecessary. But, when building a new package on :cozy_telemetry, this option is useful for some case, such as auto loading measurements modules.

about-option-reporter

 about option :reporter

The value of option :reporter specifies the reporter and its options, which is in format of {type, reporter_opts}:

about-option-poller

 about option :poller

The value of option :poller is the options of :telemetry_poller.start_link/1.