Map Last.fm error codes to error atoms

lib/last_fm/api_impl.ex

@@ -145,9 +145,24 @@ defmodule LastFm.APIImpl do
     String.replace(url, api_key, "<redacted_api_key>")
   end
 
-  defp identify_body({:ok, error = %{"error" => _error_number, "message" => _message}}) do
-    {:error, error}
+  defp identify_body({:ok, %{"error" => error_number, "message" => _message}}) do
+    {:error, map_error(error_number)}
   end
 
   defp identify_body(other), do: other
+
+  defp map_error(2), do: :invalid_service
+  defp map_error(3), do: :invalid_method
+  defp map_error(4), do: :authentication_failed
+  defp map_error(5), do: :invalid_format
+  defp map_error(6), do: :invalid_parameters
+  defp map_error(7), do: :invalid_resource
+  defp map_error(8), do: :operation_failed
+  defp map_error(9), do: :invalid_session_key
+  defp map_error(10), do: :invalid_api_key
+  defp map_error(11), do: :service_offline
+  defp map_error(13), do: :invalid_method_signature
+  defp map_error(16), do: :transient_error
+  defp map_error(26), do: :suspended_api_key
+  defp map_error(29), do: :rate_limit_exceeded
 end

lib/music_library/artists.ex

@@ -22,8 +22,7 @@ defmodule MusicLibrary.Artists do
 
   def get_artist_info(artist) do
     last_fm_config = last_fm_config()
-    # Sometimes the artist info cannot be identified with the MusicBrainz ID,
-    # because Last.fm doesn't have that information. In that case, we try again with the artist name.
+
     case last_fm_config.api.get_artist_info(
            {:musicbrainz_id, artist.musicbrainz_id},
            last_fm_config
@@ -31,8 +30,9 @@ defmodule MusicLibrary.Artists do
       {:ok, info} ->
         {:ok, info}
 
-      # TODO: remap error codes
-      {:error, %{"error" => 6}} ->
+      {:error, :invalid_parameters} ->
+        # Sometimes the artist info cannot be identified with the MusicBrainz ID,
+        # because Last.fm doesn't have that information. In that case, we try again with the artist name.
         last_fm_config.api.get_artist_info({:name, artist.name}, last_fm_config)
 
       error ->
@@ -42,8 +42,7 @@ defmodule MusicLibrary.Artists do
 
   def get_similar_artists(artist) do
     last_fm_config = last_fm_config()
-    # Sometimes the artist info cannot be identified with the MusicBrainz ID,
-    # because Last.fm doesn't have that information. In that case, we try again with the artist name.
+
     case last_fm_config.api.get_similar_artists(
            {:musicbrainz_id, artist.musicbrainz_id},
            last_fm_config
@@ -51,8 +50,9 @@ defmodule MusicLibrary.Artists do
       {:ok, info} ->
         {:ok, info}
 
-      # TODO: remap error codes
-      {:error, %{"error" => 6}} ->
+      {:error, :invalid_parameters} ->
+        # Sometimes the artist info cannot be identified with the MusicBrainz ID,
+        # because Last.fm doesn't have that information. In that case, we try again with the artist name.
         last_fm_config.api.get_similar_artists({:name, artist.name}, last_fm_config)
 
       error ->