OpenTracing in Elixir with Otter

mix.exs

defmodule Ot.Mixfile do
  use Mix.Project

  def project do
    [app: :ot,
     version: "0.1.0",
     elixir: "~> 1.4",
     build_embedded: Mix.env == :prod,
     start_permanent: Mix.env == :prod,
     deps: deps()]
  end

  def application do
    # Specify extra applications you'll use from Erlang/Elixir
    [extra_applications: [:logger]]
  end

  defp deps do
    [{:otter, "~> 0.2.0"},
     {:ibrowse, "~> 4.4"},
     {:cowboy, "~> 1.1"}]
  end
end

ot.ex

defmodule Ot do

  @moduledoc "Basic OpenTracing demo using the otter library"

  require Logger

  alias :otter, as: Otter

  @spec log_span_to_zipkin(String.t(), integer()) :: no_return()
  @spec log_span_to_zipkin(String.t()) :: no_return()

  def log_span_to_zipkin(span_name, sleep_time \\ 1000) do
    Logger.info("Constructing OT span...")
    span = span_name |> Otter.start() |> Otter.tag("OpenTracing", "Demo") |> Otter.log("Before sleep")

    Logger.info("Sleeping...")
    :timer.sleep(sleep_time)

    Logger.info("Finishing up span...")
    span |> Otter.log("After sleep") |> Otter.finish()
  end
end

If anyone stumbles upon this – the example it works perfectly with elixir 1.8, and jaeger: