akkoma/lib/pleroma/web/activity_pub/mrf/no_empty_policy.ex
2023-01-02 20:38:50 +00:00

70 lines
1.7 KiB
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Web.ActivityPub.MRF.NoEmptyPolicy do
@moduledoc "Filter local activities which have no content"
@behaviour Pleroma.Web.ActivityPub.MRF.Policy
alias Pleroma.Web.Endpoint
@impl true
def filter(%{"actor" => actor} = object) do
with true <- is_local?(actor),
true <- is_eligible_type?(object),
true <- is_note?(object),
false <- has_attachment?(object),
true <- only_mentions?(object) do
{:reject, "[NoEmptyPolicy]"}
else
_ ->
{:ok, object}
end
end
def filter(object), do: {:ok, object}
defp is_local?(actor) do
if actor |> String.starts_with?("#{Endpoint.url()}") do
true
else
false
end
end
defp has_attachment?(%{
"object" => %{"type" => "Note", "attachment" => attachments}
})
when length(attachments) > 0,
do: true
defp has_attachment?(_), do: false
defp only_mentions?(%{"object" => %{"type" => "Note", "source" => source}}) do
source =
case source do
%{"content" => text} -> text
_ -> source
end
non_mentions =
source |> String.split() |> Enum.filter(&(not String.starts_with?(&1, "@"))) |> length
if non_mentions > 0 do
false
else
true
end
end
defp only_mentions?(_), do: false
defp is_note?(%{"object" => %{"type" => "Note"}}), do: true
defp is_note?(_), do: false
defp is_eligible_type?(%{"type" => type}) when type in ["Create", "Update"], do: true
defp is_eligible_type?(_), do: false
@impl true
def describe, do: {:ok, %{}}
end