refactor: review remarks

lib/mv/application.ex

@@ -6,6 +6,7 @@ defmodule Mv.Application do
   use Application
 
   alias Mv.Helpers.SystemActor
+  alias Mv.Membership.SettingsCache
   alias Mv.Repo
   alias Mv.Vereinfacht.SyncFlash
   alias MvWeb.Endpoint
@@ -16,20 +17,28 @@ defmodule Mv.Application do
   def start(_type, _args) do
     SyncFlash.create_table!()
 
-    children = [
-      Telemetry,
-      Repo,
-      {JoinRateLimit, [clean_period: :timer.minutes(1)]},
-      {Task.Supervisor, name: Mv.TaskSupervisor},
-      {DNSCluster, query: Application.get_env(:mv, :dns_cluster_query) || :ignore},
-      {Phoenix.PubSub, name: Mv.PubSub},
-      {AshAuthentication.Supervisor, otp_app: :my},
-      SystemActor,
-      # Start a worker by calling: Mv.Worker.start_link(arg)
-      # {Mv.Worker, arg},
-      # Start to serve requests, typically the last entry
-      Endpoint
-    ]
+    # SettingsCache not started in test so get_settings runs in the test process (Ecto Sandbox).
+    cache_children =
+      if Application.get_env(:mv, :environment) == :test, do: [], else: [SettingsCache]
+
+    children =
+      [
+        Telemetry,
+        Repo
+      ] ++
+        cache_children ++
+        [
+          {JoinRateLimit, [clean_period: :timer.minutes(1)]},
+          {Task.Supervisor, name: Mv.TaskSupervisor},
+          {DNSCluster, query: Application.get_env(:mv, :dns_cluster_query) || :ignore},
+          {Phoenix.PubSub, name: Mv.PubSub},
+          {AshAuthentication.Supervisor, otp_app: :my},
+          SystemActor,
+          # Start a worker by calling: Mv.Worker.start_link(arg)
+          # {Mv.Worker, arg},
+          # Start to serve requests, typically the last entry
+          Endpoint
+        ]
 
     # See https://hexdocs.pm/elixir/Supervisor.html
     # for other strategies and supported options