Split Federation as separate context

lib/federation/activity_pub/activity_stream/converter/follower.ex

@@ -0,0 +1,37 @@
+defmodule Mobilizon.Federation.ActivityPub.ActivityStream.Converter.Follower do
+  @moduledoc """
+  Participant converter.
+
+  This module allows to convert followers from ActivityStream format to our own
+  internal one, and back.
+  """
+
+  alias Mobilizon.Actors.Actor
+  alias Mobilizon.Actors.Follower, as: FollowerModel
+
+  alias Mobilizon.Federation.ActivityPub.ActivityStream.Convertible
+
+  defimpl Convertible, for: FollowerModel do
+    alias Mobilizon.Federation.ActivityPub.ActivityStream.Converter.Follower,
+      as: FollowerConverter
+
+    defdelegate model_to_as(follower), to: FollowerConverter
+  end
+
+  @doc """
+  Convert an follow struct to an ActivityStream representation.
+  """
+  @spec model_to_as(FollowerModel.t()) :: map
+  def model_to_as(
+        %FollowerModel{actor: %Actor{} = actor, target_actor: %Actor{} = target_actor} = follower
+      ) do
+    %{
+      "type" => "Follow",
+      "actor" => actor.url,
+      "to" => [target_actor.url],
+      "cc" => ["https://www.w3.org/ns/activitystreams#Public"],
+      "object" => target_actor.url,
+      "id" => follower.url
+    }
+  end
+end