Improve ActivityPub representations (#3844)

* Improve webfinger templates and make tests more flexible

* Clean up AS2 representation of actor

* Refactor outbox

* Create activities representation

* Add representations of followers/following collections, do not redirect /users/:username route if format is empty

* Remove unused translations

* ActivityPub endpoint for single statuses, add ActivityPub::TagManager for better
URL/URI generation

* Add ActivityPub::TagManager#to

* Represent all attachments as Document instead of Image/Video specifically
(Because for remote ones we may not know for sure)

Add mentions and hashtags representation to AP notes

* Add AP-resolvable hashtag URIs

* Use ActiveModelSerializers for ActivityPub

* Clean up unused translations

* Separate route for object and activity

* Adjust cc/to matrices

* Add to/cc to activities, ensure announce activity embeds target status and
not the wrapper status, add "id" to all collections

1 files changed, 53 insertions, 0 deletions

diff --git a/app/serializers/activitypub/actor_serializer.rb b/app/serializers/activitypub/actor_serializer.rb
new file mode 100644
index 000000000..56806152e
--- /dev/null
+++ b/app/serializers/activitypub/actor_serializer.rb
@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+class ActivityPub::ActorSerializer < ActiveModel::Serializer
+  include RoutingHelper
+
+  attributes :id, :type, :following, :followers,
+             :inbox, :outbox, :preferred_username,
+             :name, :summary, :icon, :image
+
+  def id
+    account_url(object)
+  end
+
+  def type
+    'Person'
+  end
+
+  def following
+    account_following_index_url(object)
+  end
+
+  def followers
+    account_followers_url(object)
+  end
+
+  def inbox
+    nil
+  end
+
+  def outbox
+    account_outbox_url(object)
+  end
+
+  def preferred_username
+    object.username
+  end
+
+  def name
+    object.display_name
+  end
+
+  def summary
+    Formatter.instance.simplified_format(object)
+  end
+
+  def icon
+    full_asset_url(object.avatar.url(:original))
+  end
+
+  def image
+    full_asset_url(object.header.url(:original))
+  end
+end