Elixir 1.19: Inject @compile autoload opt to MRF policies

Descriptions of MRF policies are gathered at compile-time and use
Pleroma.Docs.Generator.list_behaviour_implementations func, which
depends on modules implementing the queried behaviour to be loaded.
Otherwise descriptions for MRFs can be missing from the AdminAPI route.

Note: @behaviour cannot be injected in the __using__ macro. It causes a
loop in the compiler which leads to memory exhaustion. Hence why
@behaviour is still defined separately in the MRFs.

lib/pleroma/web/activity_pub/mrf/activity_expiration_policy.ex

@@ -6,6 +6,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.ActivityExpirationPolicy do
   @moduledoc "Adds expiration to all local Create activities"
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   @impl true
   def filter(activity) do
     activity =

lib/pleroma/web/activity_pub/mrf/anti_followbot_policy.ex

@@ -3,11 +3,11 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.AntiFollowbotPolicy do
+  @moduledoc "Prevent followbots from following with a bit of heuristic"
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
   alias Pleroma.User
 
-  @moduledoc "Prevent followbots from following with a bit of heuristic"
+  use Pleroma.Web.ActivityPub.MRF.Policy
-
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
   # XXX: this should become User.normalize_by_ap_id() or similar, really.
   defp normalize_by_ap_id(%{"id" => id}), do: User.get_cached_by_ap_id(id)

lib/pleroma/web/activity_pub/mrf/anti_link_spam_policy.ex

@@ -3,9 +3,11 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.AntiLinkSpamPolicy do
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   alias Pleroma.User
 
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+  use Pleroma.Web.ActivityPub.MRF.Policy
 
   require Logger
 

lib/pleroma/web/activity_pub/mrf/anti_mention_spam_policy.ex

@@ -3,11 +3,13 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.AntiMentionSpamPolicy do
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   alias Pleroma.Config
   alias Pleroma.User
   require Pleroma.Constants
 
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+  use Pleroma.Web.ActivityPub.MRF.Policy
 
   defp user_has_posted?(%User{} = u), do: u.note_count > 0
 

lib/pleroma/web/activity_pub/mrf/drop_policy.ex

@@ -3,10 +3,12 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.DropPolicy do
-  require Logger
   @moduledoc "Drop and log everything received"
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  require Logger
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   @impl true
   def filter(activity) do
     Logger.debug("REJECTING #{inspect(activity)}")

lib/pleroma/web/activity_pub/mrf/emoji_policy.ex

@@ -3,6 +3,8 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.EmojiPolicy do
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   require Pleroma.Constants
 
   alias Pleroma.Object.Updater
@@ -10,7 +12,7 @@ defmodule Pleroma.Web.ActivityPub.MRF.EmojiPolicy do
 
   @moduledoc "Reject or force-unlisted emojis with certain URLs or names"
 
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+  use Pleroma.Web.ActivityPub.MRF.Policy
 
   defp config_remove_url do
     Pleroma.Config.get([:mrf_emoji, :remove_url], [])

lib/pleroma/web/activity_pub/mrf/ensure_re_prepended.ex

@@ -3,11 +3,13 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.EnsureRePrepended do
-  alias Pleroma.Object
-
   @moduledoc "Ensure a re: is prepended on replies to a post with a Subject"
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  alias Pleroma.Object
+
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   @reply_prefix Regex.compile!("^re:[[:space:]]*", [:caseless])
 
   def history_awareness, do: :auto

lib/pleroma/web/activity_pub/mrf/follow_bot_policy.ex

@@ -4,12 +4,15 @@
 
 defmodule Pleroma.Web.ActivityPub.MRF.FollowBotPolicy do
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   alias Pleroma.Config
   alias Pleroma.User
   alias Pleroma.Web.CommonAPI
 
   require Logger
 
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   @impl true
   def filter(activity) do
     with follower_nickname <- Config.get([:mrf_follow_bot, :follower_nickname]),

lib/pleroma/web/activity_pub/mrf/force_bot_unlisted_policy.ex

@@ -3,9 +3,12 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.ForceBotUnlistedPolicy do
-  alias Pleroma.User
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
   @moduledoc "Remove bot posts from federated timeline"
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
+  alias Pleroma.User
+
+  use Pleroma.Web.ActivityPub.MRF.Policy
 
   require Pleroma.Constants
 

lib/pleroma/web/activity_pub/mrf/force_mention.ex

@@ -3,13 +3,14 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.ForceMention do
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
   require Pleroma.Constants
 
   alias Pleroma.Config
   alias Pleroma.Object
   alias Pleroma.User
 
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+  use Pleroma.Web.ActivityPub.MRF.Policy
 
   defp get_author(url) do
     with %Object{data: %{"actor" => actor}} <- Object.normalize(url, fetch: false),

lib/pleroma/web/activity_pub/mrf/force_mentions_in_content.ex

@@ -3,13 +3,15 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.ForceMentionsInContent do
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   require Pleroma.Constants
 
   alias Pleroma.Formatter
   alias Pleroma.Object
   alias Pleroma.User
 
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+  use Pleroma.Web.ActivityPub.MRF.Policy
 
   @impl true
   def history_awareness, do: :auto

lib/pleroma/web/activity_pub/mrf/hashtag_policy.ex

@@ -3,6 +3,8 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.HashtagPolicy do
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   require Pleroma.Constants
 
   alias Pleroma.Config
@@ -14,7 +16,7 @@ defmodule Pleroma.Web.ActivityPub.MRF.HashtagPolicy do
   Note: This MRF Policy is always enabled, if you want to disable it you have to set empty lists.
   """
 
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+  use Pleroma.Web.ActivityPub.MRF.Policy
 
   @impl true
   def history_awareness, do: :manual

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

@@ -3,13 +3,14 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.HellthreadPolicy do
+  @moduledoc "Block activities with too much mentions (configurable)"
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   alias Pleroma.User
 
   require Pleroma.Constants
 
-  @moduledoc "Block activities with too much mentions (configurable)"
+  use Pleroma.Web.ActivityPub.MRF.Policy
-
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
   defp delist_activity(activity, threshold) when threshold > 0 do
     follower_collection = User.get_cached_by_ap_id(activity["actor"]).follower_address

lib/pleroma/web/activity_pub/mrf/inline_quote_policy.ex

@@ -6,6 +6,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.InlineQuotePolicy do
   @moduledoc "Force a quote line into the message content."
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   defp build_inline_quote(template, url) do
     quote_line = String.replace(template, "{url}", "<a href=\"#{url}\">#{url}</a>")
 

lib/pleroma/web/activity_pub/mrf/keyword_policy.ex

@@ -3,13 +3,15 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.KeywordPolicy do
+  @moduledoc "Reject or Word-Replace activities with a keyword or regex"
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   require Pleroma.Constants
 
   alias Pleroma.Web.ActivityPub.MRF.Utils
 
-  @moduledoc "Reject or Word-Replace activities with a keyword or regex"
 
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+  use Pleroma.Web.ActivityPub.MRF.Policy
 
   defp string_matches?(string, pattern) when is_binary(pattern) do
     String.contains?(string, pattern)

lib/pleroma/web/activity_pub/mrf/media_proxy_warming_policy.ex

@@ -6,6 +6,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.MediaProxyWarmingPolicy do
   @moduledoc "Preloads any attachments in the MediaProxy cache by prefetching them"
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   alias Pleroma.HTTP
   alias Pleroma.Web.MediaProxy
 

lib/pleroma/web/activity_pub/mrf/mention_policy.ex

@@ -4,9 +4,10 @@
 
 defmodule Pleroma.Web.ActivityPub.MRF.MentionPolicy do
   @moduledoc "Block activities which mention a user"
-
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   @impl true
   def filter(%{"type" => "Create"} = activity) do
     reject_actors = Pleroma.Config.get([:mrf_mention, :actors], [])

lib/pleroma/web/activity_pub/mrf/no_empty_policy.ex

@@ -6,6 +6,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.NoEmptyPolicy do
   @moduledoc "Filter local activities which have no content"
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   alias Pleroma.Web.Endpoint
 
   @impl true

lib/pleroma/web/activity_pub/mrf/no_op_policy.ex

@@ -6,6 +6,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.NoOpPolicy do
   @moduledoc "Does nothing (lets the messages go through unmodified)"
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   @impl true
   def filter(activity) do
     {:ok, activity}

lib/pleroma/web/activity_pub/mrf/no_placeholder_text_policy.ex

@@ -6,6 +6,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.NoPlaceholderTextPolicy do
   @moduledoc "Ensure no content placeholder is present (such as the dot from mastodon)"
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   @impl true
   def history_awareness, do: :auto
 

lib/pleroma/web/activity_pub/mrf/normalize_markup.ex

@@ -4,9 +4,11 @@
 
 defmodule Pleroma.Web.ActivityPub.MRF.NormalizeMarkup do
   @moduledoc "Scrub configured hypertext markup"
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   alias Pleroma.HTML
 
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+  use Pleroma.Web.ActivityPub.MRF.Policy
 
   @impl true
   def history_awareness, do: :auto

lib/pleroma/web/activity_pub/mrf/nsfw_api_policy.ex

@@ -38,6 +38,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.NsfwApiPolicy do
   - `unlist`: Unlist all detected NSFW content? Default: `false`
   - `reject`: Reject all detected NSFW content (takes precedence)? Default: `false`
   """
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   alias Pleroma.Config
   alias Pleroma.Constants
   alias Pleroma.HTTP
@@ -46,7 +48,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.NsfwApiPolicy do
   require Logger
   require Pleroma.Constants
 
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   @policy :mrf_nsfw_api
 
   def build_request_url(url) do

lib/pleroma/web/activity_pub/mrf/object_age_policy.ex

@@ -3,13 +3,15 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.ObjectAgePolicy do
+  @moduledoc "Filter activities depending on their age"
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   alias Pleroma.Config
   alias Pleroma.User
 
   require Pleroma.Constants
 
-  @moduledoc "Filter activities depending on their age"
+  use Pleroma.Web.ActivityPub.MRF.Policy
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
   defp check_date(%{"object" => %{"published" => published}} = activity) do
     with %DateTime{} = now <- DateTime.utc_now(),

lib/pleroma/web/activity_pub/mrf/policy.ex

@@ -15,4 +15,12 @@ defmodule Pleroma.Web.ActivityPub.MRF.Policy do
             }
   @callback history_awareness() :: :auto | :manual
   @optional_callbacks config_description: 0, history_awareness: 0, id_filter: 1
+
+  defmacro __using__(_) do
+    quote do
+      # Otherwise Pleroma.Docs.Generator.list_behaviour_implementations fails
+      # since the Elixir compiler doesn't automatically load the module since v1.19.
+      @compile {:autoload, true}
+    end
+  end
 end

lib/pleroma/web/activity_pub/mrf/quiet_reply.ex

@@ -6,11 +6,13 @@ defmodule Pleroma.Web.ActivityPub.MRF.QuietReply do
   @moduledoc """
   QuietReply alters the scope of activities from local users when replying by enforcing them to be "Unlisted" or "Quiet Public". This delivers the activity to all the expected recipients and instances, but it will not be published in the Federated / The Whole Known Network timelines. It will still be published to the Home timelines of the user's followers and visible to anyone who opens the thread.
   """
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   require Pleroma.Constants
 
   alias Pleroma.User
 
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+  use Pleroma.Web.ActivityPub.MRF.Policy
 
   @impl true
   def history_awareness, do: :auto

lib/pleroma/web/activity_pub/mrf/quote_to_link_tag_policy.ex

@@ -6,6 +6,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.QuoteToLinkTagPolicy do
   @moduledoc "Force a Link tag for posts quoting another post. (may break outgoing federation of quote posts with older Pleroma versions)"
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   alias Pleroma.Web.ActivityPub.ObjectValidators.CommonFixes
 
   require Pleroma.Constants

lib/pleroma/web/activity_pub/mrf/reject_non_public.ex

@@ -4,11 +4,12 @@
 
 defmodule Pleroma.Web.ActivityPub.MRF.RejectNonPublic do
   @moduledoc "Rejects non-public (followers-only, direct) activities"
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
   alias Pleroma.Config
   alias Pleroma.User
 
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+  use Pleroma.Web.ActivityPub.MRF.Policy
 
   require Pleroma.Constants
 

lib/pleroma/web/activity_pub/mrf/remote_report_policy.ex

@@ -2,6 +2,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.RemoteReportPolicy do
   @moduledoc "Drop remote reports if they don't contain enough information."
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   alias Pleroma.Config
 
   @impl true

lib/pleroma/web/activity_pub/mrf/simple_policy.ex

@@ -6,6 +6,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.SimplePolicy do
   @moduledoc "Filter activities depending on their origin instance"
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   alias Pleroma.Config
   alias Pleroma.FollowingRelationship
   alias Pleroma.User

lib/pleroma/web/activity_pub/mrf/steal_emoji_policy.ex

@@ -3,12 +3,14 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.StealEmojiPolicy do
+  @moduledoc "Detect new emojis by their shortcode and steals them"
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   require Logger
 
   alias Pleroma.Config
 
-  @moduledoc "Detect new emojis by their shortcode and steals them"
+  use Pleroma.Web.ActivityPub.MRF.Policy
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
   defp accept_host?(host), do: host in Config.get([:mrf_steal_emoji, :hosts], [])
 

lib/pleroma/web/activity_pub/mrf/subchain_policy.ex

@@ -3,12 +3,14 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.SubchainPolicy do
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
   alias Pleroma.Config
   alias Pleroma.Web.ActivityPub.MRF
 
   require Logger
 
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+  use Pleroma.Web.ActivityPub.MRF.Policy
 
   defp lookup_subchain(actor) do
     with matches <- Config.get([:mrf_subchain, :match_actor]),

lib/pleroma/web/activity_pub/mrf/tag_policy.ex

@@ -3,8 +3,6 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.TagPolicy do
-  alias Pleroma.User
-  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
   @moduledoc """
      Apply policies based on user tags
 
@@ -18,6 +16,11 @@ defmodule Pleroma.Web.ActivityPub.MRF.TagPolicy do
      - `mrf_tag:disable-remote-subscription`: Reject non-local follow requests
      - `mrf_tag:disable-any-subscription`: Reject any follow requests
   """
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
+  alias Pleroma.User
+
+  use Pleroma.Web.ActivityPub.MRF.Policy
 
   require Pleroma.Constants
 

lib/pleroma/web/activity_pub/mrf/user_allow_list_policy.ex

@@ -3,11 +3,13 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF.UserAllowListPolicy do
-  alias Pleroma.Config
-
   @moduledoc "Accept-list of users from specified instances"
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  alias Pleroma.Config
+
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   defp filter_by_list(activity, []), do: {:ok, activity}
 
   defp filter_by_list(%{"actor" => actor} = activity, allow_list) do

lib/pleroma/web/activity_pub/mrf/vocabulary_policy.ex

@@ -4,9 +4,10 @@
 
 defmodule Pleroma.Web.ActivityPub.MRF.VocabularyPolicy do
   @moduledoc "Filter activities which belong to certain activity vocabularies"
-
   @behaviour Pleroma.Web.ActivityPub.MRF.Policy
 
+  use Pleroma.Web.ActivityPub.MRF.Policy
+
   @impl true
   def filter(%{"type" => "Undo", "object" => object} = activity) do
     with {:ok, _} <- filter(object) do