Pleroma/lib/pleroma/web/activity_pub/mrf/hellthread_policy.ex

98 lines
2.7 KiB
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Web.ActivityPub.MRF.HellthreadPolicy do
alias Pleroma.User
require Pleroma.Constants
@moduledoc "Block messages with too much mentions (configurable)"
@behaviour Pleroma.Web.ActivityPub.MRF
defp delist_message(message, threshold) when threshold > 0 do
follower_collection = User.get_cached_by_ap_id(message["actor"]).follower_address
follower_collection? = Enum.member?(message["to"] ++ message["cc"], follower_collection)
message =
case get_recipient_count(message) do
{:public, recipients}
when follower_collection? and recipients > threshold ->
message
|> Map.put("to", [follower_collection])
|> Map.put("cc", [Pleroma.Constants.as_public()])
{:public, recipients} when recipients > threshold ->
message
|> Map.put("to", [])
|> Map.put("cc", [Pleroma.Constants.as_public()])
_ ->
message
end
{:ok, message}
end
defp delist_message(message, _threshold), do: {:ok, message}
defp reject_message(message, threshold) when threshold > 0 do
with {_, recipients} <- get_recipient_count(message) do
if recipients > threshold do
{:reject, nil}
else
{:ok, message}
end
end
end
defp reject_message(message, _threshold), do: {:ok, message}
defp get_recipient_count(message) do
recipients = (message["to"] || []) ++ (message["cc"] || [])
follower_collection = User.get_cached_by_ap_id(message["actor"]).follower_address
if Enum.member?(recipients, Pleroma.Constants.as_public()) do
recipients =
recipients
|> List.delete(Pleroma.Constants.as_public())
|> List.delete(follower_collection)
{:public, length(recipients)}
else
recipients =
recipients
|> List.delete(follower_collection)
{:not_public, length(recipients)}
end
end
@impl true
def filter(%{"type" => "Create"} = message) do
reject_threshold =
Pleroma.Config.get(
[:mrf_hellthread, :reject_threshold],
Pleroma.Config.get([:mrf_hellthread, :threshold])
)
delist_threshold = Pleroma.Config.get([:mrf_hellthread, :delist_threshold])
with {:ok, message} <- reject_message(message, reject_threshold),
{:ok, message} <- delist_message(message, delist_threshold) do
{:ok, message}
else
_e -> {:reject, nil}
end
end
@impl true
def filter(message), do: {:ok, message}
@impl true
def describe,
do: {:ok, %{mrf_hellthread: Pleroma.Config.get(:mrf_hellthread) |> Enum.into(%{})}}
end