Add OnlyMedia Upload Filter to simplify restricting uploads to audio, image, and video types

lib/pleroma/upload/filter.ex

@@ -38,9 +38,9 @@ defmodule Pleroma.Upload.Filter do
       {:ok, :noop} ->
         filter(rest, upload)
 
-      error ->
-        Logger.error("#{__MODULE__}: Filter #{filter} failed: #{inspect(error)}")
-        error
+      {:error, e} ->
+        Logger.error("#{__MODULE__}: Filter #{filter} failed: #{inspect(e)}")
+        {:error, e}
     end
   end
 end

lib/pleroma/upload/filter/only_media.ex

@@ -0,0 +1,20 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2023 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Upload.Filter.OnlyMedia do
+  @behaviour Pleroma.Upload.Filter
+  alias Pleroma.Upload
+
+  def filter(%Upload{content_type: content_type}) do
+    [type, _subtype] = String.split(content_type, "/")
+
+    if type in ["image", "video", "audio"] do
+      {:ok, :noop}
+    else
+      {:error, "Disallowed content-type: #{content_type}"}
+    end
+  end
+
+  def filter(_), do: {:ok, :noop}
+end