PromEx behaviour (PromEx v0.1.11-alpha) View Source

PromEx is a plugin based library which can be used to capture telemetry events and report them out for consumption by Prometheus. The main purpose of this particular library is to provide the behaviour that all PromEx plugins leverage so that a consistent interface can be achieved and so that leveraging multiple plugins is effortless from the user's point of view.

To use PromEx you need to define a module that uses the PromEx library. When using PromEx you have a few options available to you. For example, you can do the following:

defmodule MyApp.PromEx do
  use PromEx,
    otp_app: :web_app,
    delay_manual_start: :no_delay,
    drop_metrics_groups: [],
    upload_dashboards_on_start: true

  ...
end

The options that you can pass to PromEx are outlined in the following section. In order to tell PromEx what plugins you would like to use and what dashboards you would like PromEx to upload for you, implement the plugins/0 and dashboards/0 callbacks respectively. Each plugin also has an accompanying Grafana dashboard that you can leverage to plot all of the plugin captured data.

In order to expose captured metrics, you can leverage the PromEx provided Plug PromEx.Plug. See the PromEx.Plug documentation modules for specifics on how to use it.

Options

  • :otp_app - This is a required option and is used by PromEx to fetch the application configuration values for the various PromEx caputure modules. Make sure that this value matches the :app value in project/0 from your mix.exs file. If you use the PromEx mix prom_ex.create mix task this will be done automatically for you.

PromEx Plugins

All metrics collection will be delegated to plugins which can be found here:

Foundational metrics:

Library metrics:

Upcoming Elixir library metrics:

Backlog Elixir library metrics:

Database cron based metrics:

Link to this section Summary

Functions

A simple pass-through to fetch all of the currently configured metrics. This is primarily used by the exporter plug to fetch all of the metrics so that they can be scraped.

Link to this section Types

Link to this section Functions

Link to this function

get_metrics(prom_ex_module)

View Source

Specs

get_metrics(prom_ex_module :: module()) :: String.t() | :prom_ex_down

A simple pass-through to fetch all of the currently configured metrics. This is primarily used by the exporter plug to fetch all of the metrics so that they can be scraped.

Link to this section Callbacks

Specs

dashboards() :: list()

Specs

init_opts() :: PromEx.Config.t()

Specs

plugins() :: list()