add actors specific properties

src/Model/BaseObject.php

@@ -40,4 +40,16 @@ class BaseObject extends Base
             'duration' => null,
         ];
     }
+
+
+    public function asActor() {
+      foreach(['inbox', 'outbox', 'following', 'followers', 'liked',
+               'streams', 'preferredUsername', 'endpoints', 'proxyUrl',
+               'oautAuthorizationEndpoint', 'oauthTokenEndpoint',
+               'provideClientKey', 'signClientKey',
+               'sharedInbox'] as $attrib)
+        $this->_attribs[$attrib] = null;
+
+      return $this;
+    }
 }