Add E2EE API (#13820)

app/serializers/activitypub/one_time_key_serializer.rb

@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+class ActivityPub::OneTimeKeySerializer < ActivityPub::Serializer
+  context :security
+
+  context_extensions :olm
+
+  class SignatureSerializer < ActivityPub::Serializer
+    attributes :type, :signature_value
+
+    def type
+      'Ed25519Signature'
+    end
+
+    def signature_value
+      object.signature
+    end
+  end
+
+  attributes :key_id, :type, :public_key_base64
+
+  has_one :signature, serializer: SignatureSerializer
+
+  def type
+    'Curve25519Key'
+  end
+
+  def public_key_base64
+    object.key
+  end
+
+  def signature
+    object
+  end
+end