git.squeep.com Git - akkoma/blob - lib/pleroma/web/activity_pub/mrf/hashtag_policy.ex

   1 # Pleroma: A lightweight social networking server
   2 # Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
   3 # SPDX-License-Identifier: AGPL-3.0-only
   4
   5 defmodule Pleroma.Web.ActivityPub.MRF.HashtagPolicy do
   6   require Pleroma.Constants
   7
   8   alias Pleroma.Config
   9   alias Pleroma.Object
  10
  11   @moduledoc """
  12   Reject, TWKN-remove or Set-Sensitive messsages with specific hashtags (without the leading #)
  13
  14   Note: This MRF Policy is always enabled, if you want to disable it you have to set empty lists.
  15   """
  16
  17   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
  18
  19   @impl true
  20   def history_awareness, do: :manual
  21
  22   defp check_reject(message, hashtags) do
  23     if Enum.any?(Config.get([:mrf_hashtag, :reject]), fn match -> match in hashtags end) do
  24       {:reject, "[HashtagPolicy] Matches with rejected keyword"}
  25     else
  26       {:ok, message}
  27     end
  28   end
  29
  30   defp check_ftl_removal(%{"to" => to} = message, hashtags) do
  31     if Pleroma.Constants.as_public() in to and
  32          Enum.any?(Config.get([:mrf_hashtag, :federated_timeline_removal]), fn match ->
  33            match in hashtags
  34          end) do
  35       to = List.delete(to, Pleroma.Constants.as_public())
  36       cc = [Pleroma.Constants.as_public() | message["cc"] || []]
  37
  38       message =
  39         message
  40         |> Map.put("to", to)
  41         |> Map.put("cc", cc)
  42         |> Kernel.put_in(["object", "to"], to)
  43         |> Kernel.put_in(["object", "cc"], cc)
  44
  45       {:ok, message}
  46     else
  47       {:ok, message}
  48     end
  49   end
  50
  51   defp check_ftl_removal(message, _hashtags), do: {:ok, message}
  52
  53   defp check_sensitive(message) do
  54     {:ok, new_object} =
  55       Object.Updater.do_with_history(message["object"], fn object ->
  56         hashtags = Object.hashtags(%Object{data: object})
  57
  58         if Enum.any?(Config.get([:mrf_hashtag, :sensitive]), fn match -> match in hashtags end) do
  59           {:ok, Map.put(object, "sensitive", true)}
  60         else
  61           {:ok, object}
  62         end
  63       end)
  64
  65     {:ok, Map.put(message, "object", new_object)}
  66   end
  67
  68   @impl true
  69   def filter(%{"type" => type, "object" => object} = message) when type in ["Create", "Update"] do
  70     history_items =
  71       with %{"formerRepresentations" => %{"orderedItems" => items}} <- object do
  72         items
  73       else
  74         _ -> []
  75       end
  76
  77     historical_hashtags =
  78       Enum.reduce(history_items, [], fn item, acc ->
  79         acc ++ Object.hashtags(%Object{data: item})
  80       end)
  81
  82     hashtags = Object.hashtags(%Object{data: object}) ++ historical_hashtags
  83
  84     if hashtags != [] do
  85       with {:ok, message} <- check_reject(message, hashtags),
  86            {:ok, message} <-
  87              (if "type" == "Create" do
  88                 check_ftl_removal(message, hashtags)
  89               else
  90                 {:ok, message}
  91               end),
  92            {:ok, message} <- check_sensitive(message) do
  93         {:ok, message}
  94       end
  95     else
  96       {:ok, message}
  97     end
  98   end
  99
 100   @impl true
 101   def filter(message), do: {:ok, message}
 102
 103   @impl true
 104   def describe do
 105     mrf_hashtag =
 106       Config.get(:mrf_hashtag)
 107       |> Enum.into(%{})
 108
 109     {:ok, %{mrf_hashtag: mrf_hashtag}}
 110   end
 111
 112   @impl true
 113   def config_description do
 114     %{
 115       key: :mrf_hashtag,
 116       related_policy: "Pleroma.Web.ActivityPub.MRF.HashtagPolicy",
 117       label: "MRF Hashtag",
 118       description: @moduledoc,
 119       children: [
 120         %{
 121           key: :reject,
 122           type: {:list, :string},
 123           description: "A list of hashtags which result in message being rejected.",
 124           suggestions: ["foo"]
 125         },
 126         %{
 127           key: :federated_timeline_removal,
 128           type: {:list, :string},
 129           description:
 130             "A list of hashtags which result in message being removed from federated timelines (a.k.a unlisted).",
 131           suggestions: ["foo"]
 132         },
 133         %{
 134           key: :sensitive,
 135           type: {:list, :string},
 136           description:
 137             "A list of hashtags which result in message being set as sensitive (a.k.a NSFW/R-18)",
 138           suggestions: ["nsfw", "r18"]
 139         }
 140       ]
 141     }
 142   end
 143 end