Put HTTPSignatures, WebFinger and ActivityStream alongside with ActivityPub

lib/federation/activity_stream/converter/tombstone.ex

@@ -0,0 +1,41 @@
+defmodule Mobilizon.Federation.ActivityStream.Converter.Tombstone do
+  @moduledoc """
+  Comment converter.
+
+  This module allows to convert Tombstone models to ActivityStreams data
+  """
+
+  alias Mobilizon.Tombstone, as: TombstoneModel
+
+  alias Mobilizon.Federation.ActivityStream.{Converter, Convertible}
+
+  require Logger
+
+  @behaviour Converter
+
+  defimpl Convertible, for: TombstoneModel do
+    alias Mobilizon.Federation.ActivityStream.Converter.Tombstone, as: TombstoneConverter
+
+    defdelegate model_to_as(comment), to: TombstoneConverter
+  end
+
+  @doc """
+  Make an AS tombstone object from an existing `Tombstone` structure.
+  """
+  @impl Converter
+  @spec model_to_as(TombstoneModel.t()) :: map
+  def model_to_as(%TombstoneModel{} = tombstone) do
+    %{
+      "type" => "Tombstone",
+      "id" => tombstone.uri,
+      "deleted" => tombstone.inserted_at
+    }
+  end
+
+  @doc """
+  Converting an Tombstone to an object makes no sense, nevertheless…
+  """
+  @impl Converter
+  @spec as_to_model_data(map) :: map
+  def as_to_model_data(object), do: object
+end