Setup TokenFetcher for :arena_load_test app

apps/arena_load_test/lib/arena_load_test/application.ex

@@ -9,7 +9,9 @@ defmodule ArenaLoadTest.Application do
   def start(_type, _args) do
     children = [
       ArenaLoadTest.SocketSupervisor,
-      ArenaLoadTest.LoadtestManager
+      ArenaLoadTest.LoadtestManager,
+      {Finch, name: ArenaLoadTest.Finch},
+      ArenaLoadTest.TokenFetcher
       # Starts a worker by calling: ArenaLoadTest.Worker.start_link(arg)
       # {ArenaLoadTest.Worker, arg}
     ]

apps/arena_load_test/lib/arena_load_test/token_fetcher.ex

@@ -0,0 +1,47 @@
+defmodule ArenaLoadTest.TokenFetcher do
+  @moduledoc """
+  GenServer that calls gateway to create and refresh a JWT token used by the bots
+  """
+  use GenServer
+
+  def get_auth() do
+    GenServer.call(__MODULE__, :get_auth)
+  end
+
+  def start_link(_args) do
+    GenServer.start_link(__MODULE__, [], name: __MODULE__)
+  end
+
+  @impl true
+  def init(_) do
+    Process.send_after(self(), :fetch_token, 500)
+    {:ok, %{}}
+  end
+
+  @impl true
+  def handle_call(:get_auth, _, state) do
+    {:reply, state, state}
+  end
+
+  @impl true
+  def handle_info(:fetch_token, state) do
+    gateway_url = Application.get_env(:arena_load_test, :gateway_url)
+    secret = :crypto.strong_rand_bytes(32) |> Base.url_encode64
+    payload = Jason.encode!(%{"bot_secret" => secret})
+
+    result =
+      Finch.build(:post, "#{gateway_url}/auth/generate-bot-token", [{"content-type", "application/json"}], payload)
+      |> Finch.request(ArenaLoadTest.Finch)
+
+    case result do
+      {:ok, %Finch.Response{status: 200, body: body}} ->
+        Process.send_after(self(), :fetch_token, 1_800_000)
+        %{"token" => token} = Jason.decode!(body)
+        {:noreply, %{token: token, secret: secret}}
+
+      _else_error ->
+        Process.send_after(self(), :fetch_token, 5_000)
+        {:noreply, state}
+    end
+  end
+end

apps/arena_load_test/mix.exs

@@ -27,7 +27,8 @@ defmodule ArenaLoadTest.MixProject do
   defp deps do
     [
       {:websockex, "~> 0.4.3"},
-      {:protobuf, "~> 0.12.0"}
+      {:protobuf, "~> 0.12.0"},
+      {:finch, "~> 0.13"}
       # {:dep_from_hexpm, "~> 0.3.0"},
       # {:dep_from_git, git: "https://github.com/elixir-lang/my_dep.git", tag: "0.1.0"},
       # {:sibling_app_in_umbrella, in_umbrella: true}

config/runtime.exs

@@ -401,4 +401,11 @@ config :bot_manager, :end_point_configuration,
   plug: BotManager.Endpoint,
   options: [port: bot_manager_port]
 
+
+###################################
+# App configuration: Bot Manager  #
+###################################
+
+config :arena_load_test, :gateway_url, System.get_env("GATEWAY_URL") || "http://localhost:4001"
+
 ###################################