Added a new file that runs post-boot when the app is ready to serve requests; put yt-dlp updater in there

lib/pinchflat/application.ex

@@ -9,8 +9,12 @@ defmodule Pinchflat.Application do
   @impl true
   def start(_type, _args) do
     check_and_update_timezone()
+    attach_oban_telemetry()
+    Logger.add_handlers(:pinchflat)
 
-    children = [
+    # See https://hexdocs.pm/elixir/Supervisor.html
+    # for other strategies and supported options
+    [
       Pinchflat.PromEx,
       PinchflatWeb.Telemetry,
       Pinchflat.Repo,
@@ -24,17 +28,11 @@ defmodule Pinchflat.Application do
       {Finch, name: Pinchflat.Finch},
       # Start a worker by calling: Pinchflat.Worker.start_link(arg)
       # {Pinchflat.Worker, arg},
-      # Start to serve requests, typically the last entry
-      PinchflatWeb.Endpoint
+      # Start to serve requests, typically the last entry (except for the post-boot tasks)
+      PinchflatWeb.Endpoint,
+      Pinchflat.Boot.PostBootStartupTasks
     ]
-
-    attach_oban_telemetry()
-    Logger.add_handlers(:pinchflat)
-
-    # See https://hexdocs.pm/elixir/Supervisor.html
-    # for other strategies and supported options
-    opts = [strategy: :one_for_one, name: Pinchflat.Supervisor]
-    Supervisor.start_link(children, opts)
+    |> Supervisor.start_link(strategy: :one_for_one, name: Pinchflat.Supervisor)
   end
 
   # Tell Phoenix to update the endpoint configuration

lib/pinchflat/boot/post_boot_startup_tasks.ex

@@ -0,0 +1,46 @@
+defmodule Pinchflat.Boot.PostBootStartupTasks do
+  @moduledoc """
+  This module is responsible for running startup tasks on app boot
+  AFTER all other boot steps have taken place and the app is ready to serve requests.
+
+  It's a GenServer because that plays REALLY nicely with the existing
+  Phoenix supervision tree.
+  """
+
+  alias Pinchflat.YtDlp.UpdateWorker, as: YtDlpUpdateWorker
+
+  # restart: :temporary means that this process will never be restarted (ie: will run once and then die)
+  use GenServer, restart: :temporary
+  import Ecto.Query, warn: false
+
+  def start_link(opts \\ []) do
+    GenServer.start_link(__MODULE__, %{env: Application.get_env(:pinchflat, :env)}, opts)
+  end
+
+  @doc """
+  Runs post-boot application startup tasks.
+
+  Any code defined here will run every time the application starts. You must
+  make sure that the code is idempotent and safe to run multiple times.
+
+  This is a good place to set up default settings, create initial records, stuff like that.
+  Should be fast - anything with the potential to be slow should be kicked off as a job instead.
+  """
+  @impl true
+  def init(%{env: :test} = state) do
+    # Do nothing _as part of the app bootup process_.
+    # Since bootup calls `start_link` and that's where the `env` state is injected,
+    # you can still call `.init()` manually to run these tasks for testing purposes
+    {:ok, state}
+  end
+
+  def init(state) do
+    update_yt_dlp()
+
+    {:ok, state}
+  end
+
+  defp update_yt_dlp do
+    YtDlpUpdateWorker.kickoff()
+  end
+end

test/pinchflat/boot/post_boot_startup_tasks_test.exs

@@ -0,0 +1,26 @@
+defmodule Pinchflat.Boot.PostBootStartupTasksTest do
+  use Pinchflat.DataCase
+
+  # import Pinchflat.JobFixtures
+
+  # alias Pinchflat.Settings
+  alias Pinchflat.YtDlp.UpdateWorker
+  alias Pinchflat.Boot.PostBootStartupTasks
+
+  setup do
+    stub(YtDlpRunnerMock, :update, fn -> {:ok, "1"} end)
+    stub(YtDlpRunnerMock, :version, fn -> {:ok, "1"} end)
+
+    :ok
+  end
+
+  describe "update_yt_dlp" do
+    test "enqueues an update job" do
+      assert [] = all_enqueued(worker: UpdateWorker)
+
+      PostBootStartupTasks.init(%{})
+
+      assert [%Oban.Job{}] = all_enqueued(worker: UpdateWorker)
+    end
+  end
+end