Add RichMediaController and tests

lib/pleroma/web/rich_media/parser.ex

@@ -4,11 +4,23 @@ defmodule Pleroma.Web.RichMedia.Parser do
   def parse(url) do
     {:ok, %Tesla.Env{body: html}} = Pleroma.HTTP.get(url)
 
-    Enum.reduce_while(@parsers, %Pleroma.Web.RichMedia.Data{}, fn parser, acc ->
+    html |> maybe_parse() |> get_parsed_data()
+  end
+
+  defp maybe_parse(html) do
+    Enum.reduce_while(@parsers, %{}, fn parser, acc ->
       case parser.parse(html, acc) do
         {:ok, data} -> {:halt, data}
         {:error, _msg} -> {:cont, acc}
       end
     end)
   end
+
+  defp get_parsed_data(data) when data == %{} do
+    {:error, "No metadata found"}
+  end
+
+  defp get_parsed_data(data) do
+    {:ok, data}
+  end
 end