Prometheus.ex - Prometheus.io Elixir integrations

For those new to monitoring (like myself), I wrote a blog post on how to set this up:

Thank you! Excellent post. Just a note: prometheus_plugs can also instrument a single plug or it’s own pipeline:

defmodule EnsureAuthenticatedInstrumenter do
  use Prometheus.PlugInstrumenter

  plug Guardian.Plug.EnsureAuthenticated

  def label_value(:authenticated, {conn, _}) do
    conn.status != 401
  end
end

Basically it uses Plug.Builder and similar to it in this aspect.

I just pushed version 3.0.1 of Prometheus.erl with huge performance update:

prometheus_ets_optimization.png502×1026 56.3 KB

Run mix deps.update prometheus to update!

Update:

• Prometheus.ex - mnesia contrib (e.g. calculate full space occupied by a table on disk);
• Prometheus Plugs - content negotiation is turned on now. I.e. exporter should render text when request comes from browser and Protobuf when it comes from prometheus server. Format set to :auto by default.

I also have Slack channel (prometheus) now: Browser link.

New stuff:

• GitHub - deadtrickster/prometheus-push: Prometheus.io pushgateway client · GitHub - :httpc-based Pushgateway client;
• GitHub - prometheus-erl/prometheus-httpd: Expose Prometheus metrics using inets httpd. · GitHub - to expose /metrics using just httpd from inets.
• GitHub - prometheus-erl/beam-dashboards: BEAM Prometheus Grafana · GitHub - Beam Grafana dashboards collection (my phoenix/plugs/ecto dashboards are coming soon. Please consider contributing yours!)

Just released new version:

• Boolean metric;
• Text format rendering optimization (> 30% faster).

Github: GitHub - prometheus-erl/prometheus.ex: Prometheus.io Elixir client · GitHub
Hex.pm: prometheus_ex | Hex

Many thanks for your work. It’s very useful to have integrations with Prometheus. (Even if I haven’t used Elixir in production)

Thanks for your work on this. I found it pretty easy to get set up with and the docs were helpful. The pull-based model Prometheus uses is really great to get started easily sending metrics with a very small amount of overhead.

To people evaluating open source metrics solutions, would recommend based on my early experience.

This is really cool @deadtrickster, thank you! Are there any kind of guide i can follow, if i want to push my own metrics, which are more business oriented, like user signups etc.

It’s all there in the README. For user signups, you probably want a counter. Lifting directly from the API docs, and doing some renaming:

defmodule UserSignupInstrumenter do

  use Prometheus.Metric

  ## to be called at app/supervisor startup.
  ## to tolerate restarts use declare.
  def setup() do
    Counter.declare([name: :my_service_user_signups_total,
                     help: "User signups count.",
                     labels: [:country]])
  end

  def inc(country) do
    Counter.inc([name: : my_service_user_signups_total,
                labels: [country]])
  end

end

Then from the places in your code where you handle user signups:

def handle_signup(user, other, stuff) do
  # create the user here
  country = MyGeoIPService.lookup_country(user)
  UserSignupInstrumenter.inc(country)
end

I made up a country label, so you can track user signups on a per-country basis. Not sure how useful it might be or not