Provide metrics on root URL

mix.exs

@@ -6,25 +6,41 @@ defmodule KafkaexLagExporter.MixProject do
       app: :kafkaex_lag_exporter,
       version: "0.1.0",
       elixir: "~> 1.13",
+      elixirc_paths: elixirc_paths(Mix.env()),
+      compilers: Mix.compilers(),
       start_permanent: Mix.env() == :prod,
       deps: deps()
     ]
   end
 
-  # Run "mix help compile.app" to learn about applications.
+  # Configuration for the OTP application.
+  #
+  # Type `mix help compile.app` for more information.
   def application do
     [
-      extra_applications: [:logger],
-      mod: { KafkaexLagExporter, [] },
+      mod: {KafkaexLagExporter.Application, []},
+      extra_applications: [:logger, :runtime_tools]
     ]
   end
 
-  # Run "mix help deps" to learn about dependencies.
+  # Specifies which paths to compile per environment.
+  defp elixirc_paths(:test), do: ["lib", "test/support"]
+  defp elixirc_paths(_), do: ["lib"]
+
+  # Specifies your project dependencies.
+  #
+  # Type `mix help deps` for examples and options.
   defp deps do
     [
+      {:phoenix, "~> 1.6.6"},
+      {:telemetry_metrics, "~> 0.6"},
+      {:telemetry_poller, "~> 1.0"},
+      {:jason, "~> 1.2"},
+      {:plug_cowboy, "~> 2.5"},
       {:credo, "~> 1.6", only: [:dev, :test], runtime: false},
       {:dialyxir, "~> 1.0", only: [:dev], runtime: false},
       {:kafka_ex, "~> 0.12.1"},
+      {:prom_ex, "~> 1.6.0"}
     ]
   end
 end