Add LastFm feed for a given user

lib/last_fm/refresh.ex

@@ -0,0 +1,35 @@
+defmodule LastFm.Refresh do
+  use GenServer
+
+  require Logger
+
+  alias LastFm.{API, Feed}
+
+  @refresh_interval System.convert_time_unit(30, :second, :millisecond)
+
+  def start_link(config) do
+    GenServer.start_link(__MODULE__, config, name: __MODULE__)
+  end
+
+  def init(config) do
+    if config.api_key do
+      {:ok, config, {:continue, :refresh}}
+    else
+      :ignore
+    end
+  end
+
+  def handle_continue(:refresh, config) do
+    case API.get_recent_tracks(config.user, config.api_key) do
+      {:ok, tracks} ->
+        Feed.update(tracks)
+        Process.send_after(self(), :refresh, @refresh_interval)
+        {:noreply, config}
+
+      {:error, _reason} ->
+        # TODO: think about failure scenario - error is logged at the API level
+        Process.send_after(self(), :refresh, @refresh_interval)
+        {:noreply, config}
+    end
+  end
+end