To get artist info, try mbid and then artist name

lib/last_fm/api_behaviour.ex

@@ -2,7 +2,9 @@ defmodule LastFm.APIBehaviour do
   alias LastFm.{Artist, Config, Track}
 
   @type musicbrainz_id :: String.t()
+  @type name :: String.t()
   @type config :: Config.t()
   @callback get_recent_tracks(config) :: {:ok, [Track.t()]} | {:error, String.t()}
-  @callback get_artist_info(musicbrainz_id, config) :: {:ok, Artist.t()} | {:error, String.t()}
+  @callback get_artist_info({:musicbrainz_id, musicbrainz_id} | {:name, name}, config) ::
+              {:ok, Artist.t()} | {:error, String.t()}
 end

lib/last_fm/api_impl.ex

@@ -47,16 +47,25 @@ defmodule LastFm.APIImpl do
   end
 
   @impl true
-  def get_artist_info(artist_mbid, config) do
+  def get_artist_info({:musicbrainz_id, artist_mbid}, config) do
-    options = [
+    do_get_artist_info([mbid: artist_mbid], config)
+  end
+
+  def get_artist_info({:name, artist_name}, config) do
+    do_get_artist_info([artist: artist_name], config)
+  end
+
+  def do_get_artist_info(options, config) do
+    base_options = [
       method: "artist.getInfo",
       api_key: config.api_key,
       user: config.user,
-      mbid: artist_mbid,
       format: "json",
       limit: 50
     ]
 
+    options = Keyword.merge(base_options, options)
+
     url = @base_url <> "?" <> URI.encode_query(options)
 
     Logger.debug("Fetching data from #{sanitize_url(url, config.api_key)}")
@@ -68,12 +77,12 @@ defmodule LastFm.APIImpl do
          |> Map.get("artist")
          |> Artist.from_api_response()}
 
-      other ->
+      error ->
         msg =
-          "Failed to fetch data from #{sanitize_url(url, config.api_key)}, reason: #{inspect(other)}"
+          "Failed to fetch data from #{sanitize_url(url, config.api_key)}, reason: #{inspect(error)}"
 
         Logger.error(msg)
-        {:error, msg}
+        error
     end
   end
 
@@ -97,8 +106,8 @@ defmodule LastFm.APIImpl do
     String.replace(url, api_key, "<redacted_api_key>")
   end
 
-  defp identify_body({:ok, %{"error" => error_number, "message" => message}}) do
+  defp identify_body({:ok, error = %{"error" => _error_number, "message" => _message}}) do
-    {:error, "Error #{error_number}: #{message}"}
+    {:error, error}
   end
 
   defp identify_body(other), do: other

lib/music_library/records.ex

@@ -110,9 +110,24 @@ defmodule MusicLibrary.Records do
     Repo.all(q)
   end
 
-  def get_artist_info(musicbrainz_id) do
+  def get_artist_info(artist) do
     last_fm_config = last_fm_config()
-    last_fm_config.api.get_artist_info(musicbrainz_id, 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
+         ) do
+      {:ok, info} ->
+        {:ok, info}
+
+      # TODO: remap error codes
+      {:error, %{"error" => 6}} ->
+        last_fm_config.api.get_artist_info({:name, artist.name}, last_fm_config)
+
+      error ->
+        error
+    end
   end
 
   def get_cover(id) do

lib/music_library_web/live/artist_live/show.ex

@@ -23,7 +23,7 @@ defmodule MusicLibraryWeb.ArtistLive.Show do
      |> assign(:artist, artist)
      |> assign(:artist_records, grouped_artist_records)
      |> assign_async(:artist_info, fn ->
-       with {:ok, artist_info} <- Records.get_artist_info(musicbrainz_id) do
+       with {:ok, artist_info} <- Records.get_artist_info(artist) do
          {:ok, %{artist_info: artist_info}}
        end
      end)

test/music_library_web/live/artist_live/show_test.exs

@@ -23,7 +23,8 @@ defmodule MusicLibraryWeb.ArtistLive.ShowTest do
       [artist] = collection_record.artists
       artist_musicbrainz_id = artist.musicbrainz_id
 
-      expect(APIBehaviourMock, :get_artist_info, fn ^artist_musicbrainz_id, _config ->
+      expect(APIBehaviourMock, :get_artist_info, fn {:musicbrainz_id, ^artist_musicbrainz_id},
+                                                    _config ->
         {:ok,
          artist_get_info()
          |> Map.get("artist")