After "mix phx.gen.auth Accounts User users".

lib/beet_round_server/accounts/scope.ex

@@ -0,0 +1,33 @@
+defmodule BeetRoundServer.Accounts.Scope do
+  @moduledoc """
+  Defines the scope of the caller to be used throughout the app.
+
+  The `BeetRoundServer.Accounts.Scope` allows public interfaces to receive
+  information about the caller, such as if the call is initiated from an
+  end-user, and if so, which user. Additionally, such a scope can carry fields
+  such as "super user" or other privileges for use as authorization, or to
+  ensure specific code paths can only be access for a given scope.
+
+  It is useful for logging as well as for scoping pubsub subscriptions and
+  broadcasts when a caller subscribes to an interface or performs a particular
+  action.
+
+  Feel free to extend the fields on this struct to fit the needs of
+  growing application requirements.
+  """
+
+  alias BeetRoundServer.Accounts.User
+
+  defstruct user: nil
+
+  @doc """
+  Creates a scope for the given user.
+
+  Returns nil if no user is given.
+  """
+  def for_user(%User{} = user) do
+    %__MODULE__{user: user}
+  end
+
+  def for_user(nil), do: nil
+end