Merge branch 'develop' into issue/1023
[akkoma] / lib / pleroma / web / activity_pub / mrf / anti_followbot_policy.ex
index 7c6ad582ae9ab6e652d4224931d6451eed461407..b96388489170b4e5c385817f8473aaa4d0cc425c 100644 (file)
@@ -1,10 +1,12 @@
 # Pleroma: A lightweight social networking server
-# Copyright © 2019 Pleroma Authors <https://pleroma.social/>
+# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.AntiFollowbotPolicy do
   alias Pleroma.User
 
+  @moduledoc "Prevent followbots from following with a bit of heuristic"
+
   @behaviour Pleroma.Web.ActivityPub.MRF
 
   # XXX: this should become User.normalize_by_ap_id() or similar, really.
@@ -23,15 +25,25 @@ defmodule Pleroma.Web.ActivityPub.MRF.AntiFollowbotPolicy do
   defp score_displayname(_), do: 0.0
 
   defp determine_if_followbot(%User{nickname: nickname, name: displayname}) do
+    # nickname will be a binary string except when following a relay
     nick_score =
-      nickname
-      |> String.downcase()
-      |> score_nickname()
+      if is_binary(nickname) do
+        nickname
+        |> String.downcase()
+        |> score_nickname()
+      else
+        0.0
+      end
 
+    # displayname will either be a binary string or nil, if a displayname isn't set.
     name_score =
-      displayname
-      |> String.downcase()
-      |> score_displayname()
+      if is_binary(displayname) do
+        displayname
+        |> String.downcase()
+        |> score_displayname()
+      else
+        0.0
+      end
 
     nick_score + name_score
   end
@@ -48,10 +60,13 @@ defmodule Pleroma.Web.ActivityPub.MRF.AntiFollowbotPolicy do
     if score < 0.8 do
       {:ok, message}
     else
-      {:reject, nil}
+      {:reject, "[AntiFollowbotPolicy] Scored #{actor_id} as #{score}"}
     end
   end
 
   @impl true
   def filter(message), do: {:ok, message}
+
+  @impl true
+  def describe, do: {:ok, %{}}
 end