Update

lib/nulla_web/controllers/api/announce_json.ex

@@ -0,0 +1,23 @@
+defmodule NullaWeb.Api.AnnounceJSON do
+  alias Nulla.Announces.Announce
+
+  @doc """
+  Renders a list of announces.
+  """
+  def index(%{announces: announces}) do
+    %{data: for(announce <- announces, do: data(announce))}
+  end
+
+  @doc """
+  Renders a single announce.
+  """
+  def show(%{announce: announce}) do
+    %{data: data(announce)}
+  end
+
+  defp data(%Announce{} = announce) do
+    %{
+      id: announce.id
+    }
+  end
+end