How to use the sockethub-schemas.ActivityObject function in sockethub-schemas

const tv4       = require('tv4'),
      debug     = require('debug')('sockethub:bootstrap:init'),
      nconf     = require('nconf');

debug('running init routines');

const packageJSON    = require('./../../package.json');
const junk = require(__dirname + '/config.js')();
const platforms = require(__dirname + '/platforms.js')(Object.keys(packageJSON.dependencies));
const SockethubSchemas = require('sockethub-schemas');

// load sockethub-activity-stream schema and register it with tv4
tv4.addSchema(SockethubSchemas.ActivityStream.id, SockethubSchemas.ActivityStream);
// load sockethub-activity-object schema and register it with tv4
tv4.addSchema(SockethubSchemas.ActivityObject.id, SockethubSchemas.ActivityObject);

function defaultEnvParams(host, port, prop) {
  nconf.set(prop + ':host', host);
  nconf.set(prop + ':port', port);
}

defaultEnvParams(
  process.env.HOST || nconf.get('service:host'),
  process.env.PORT || nconf.get('service:port'),
  'service'
);
defaultEnvParams(
  process.env.REDIS_HOST || nconf.get('redis:host'),
  process.env.REDIS_PORT || nconf.get('redis:port'),
  'redis'
);

import URI from 'urijs';
import ActivityStreams from 'activity-streams';
import * as SockethubSchemas from 'sockethub-schemas';

import init from './bootstrap/init';
import config from './config';

const activity = ActivityStreams(config.get('activity-streams:opts')),
      log = debug('sockethub:validate');

// load sockethub-activity-stream schema and register it with tv4
// http://sockethub.org/schemas/v0/activity-stream#
tv4.addSchema(SockethubSchemas.ActivityStream.id, SockethubSchemas.ActivityStream);
// load sockethub-activity-object schema and register it with tv4
// http://sockethub.org/schemas/v0/activity-object#
tv4.addSchema(SockethubSchemas.ActivityObject.id, SockethubSchemas.ActivityObject);

// educated guess on what the displayName is, if it's not defined
// since we know the @id is a URI, we prioritize by username, then fragment (no case yet for path)
function ensureDisplayName(msg) {
  if ((msg['@id']) && (! msg.displayName)) {
    const uri = new URI(msg['@id']);
    return uri.username() || getUriFragment(uri) || uri.path();
  }
  return msg.displayName;
}

function ensureObject(msg) {
  return !((typeof msg !== 'object') || (Array.isArray(msg)));
}

function errorHandler(type, msg, next) {

function validateActivityObject(msg) {
  return tv4.validate({ object: msg }, SockethubSchemas.ActivityObject);
}