Create new stream event type: emoji_reaction

app/serializers/activitypub/undo_emoji_reaction_serializer.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+class ActivityPub::UndoEmojiReactionSerializer < ActivityPub::Serializer
+  attributes :id, :type, :actor, :content
+
+  has_one :object, serializer: ActivityPub::EmojiReactionSerializer
+
+  def id
+    [ActivityPub::TagManager.instance.uri_for(object.account), '#emoji_reactions/', object.id, '/undo'].join
+  end
+
+  def type
+    'Undo'
+  end
+
+  def actor
+    ActivityPub::TagManager.instance.uri_for(object.account)
+  end
+
+  def content
+    object.custom_emoji.nil? ? object.name : ":#{object.name}:"
+  end
+end