1 files changed, 59 insertions, 0 deletions
diff --git a/lib/pleroma/web/activity_pub/mrf/follow_bot_policy.ex b/lib/pleroma/web/activity_pub/mrf/follow_bot_policy.ex
new file mode 100644
index 000000000..7307c9c14
--- /dev/null
+++ b/lib/pleroma/web/activity_pub/mrf/follow_bot_policy.ex
@@ -0,0 +1,59 @@
+defmodule Pleroma.Web.ActivityPub.MRF.FollowBotPolicy do
+  @behaviour Pleroma.Web.ActivityPub.MRF
+  alias Pleroma.Config
+  alias Pleroma.User
+  alias Pleroma.Web.CommonAPI
+
+  require Logger
+
+  @impl true
+  def filter(message) do
+    with follower_nickname <- Config.get([:mrf_follow_bot, :follower_nickname]),
+         %User{actor_type: "Service"} = follower <-
+           User.get_cached_by_nickname(follower_nickname),
+         %{"type" => "Create", "object" => %{"type" => "Note"}} <- message do
+      try_follow(follower, message)
+    else
+      nil ->
+        Logger.warn(
+          "#{__MODULE__} skipped because of missing `:mrf_follow_bot, :follower_nickname` configuration, the :follower_nickname
+            account does not exist, or the account is not correctly configured as a bot."
+        )
+
+        {:ok, message}
+
+      _ ->
+        {:ok, message}
+    end
+  end
+
+  defp try_follow(follower, message) do
+    to = Map.get(message, "to", [])
+    cc = Map.get(message, "cc", [])
+    actor = [message["actor"]]
+
+    Enum.concat([to, cc, actor])
+    |> List.flatten()
+    |> Enum.uniq()
+    |> User.get_all_by_ap_id()
+    |> Enum.each(fn user ->
+      with false <- user.local,
+           false <- User.following?(follower, user),
+           false <- User.locked?(user),
+           false <- (user.bio || "") |> String.downcase() |> String.contains?("nobot") do
+        Logger.debug(
+          "#{__MODULE__}: Follow request from #{follower.nickname} to #{user.nickname}"
+        )
+
+        CommonAPI.follow(follower, user)
+      end
+    end)
+
+    {:ok, message}
+  end
+
+  @impl true
+  def describe do
+    {:ok, %{}}
+  end
+end