def sync_beacons(saltenv=None, refresh=True, extmod_whitelist=None, extmod_blacklist=None):
    '''
    .. versionadded:: 2015.5.1

    Sync beacons from ``salt://_beacons`` to the minion

    saltenv
        The fileserver environment from which to sync. To sync from more than
        one environment, pass a comma-separated list.

        If not passed, then all environments configured in the :ref:`top files
        <states-top>` will be checked for beacons to sync. If no top files are
        found, then the ``base`` environment will be synced.

    refresh : True
        If ``True``, refresh the available beacons on the minion. This refresh
        will be performed even if no new beacons are synced. Set to ``False``
        to prevent this refresh.

    extmod_whitelist : None
        comma-seperated list of modules to sync

    extmod_blacklist : None
        comma-seperated list of modules to blacklist based on type

    CLI Example:

    .. code-block:: bash

        salt '*' saltutil.sync_beacons
        salt '*' saltutil.sync_beacons saltenv=dev
        salt '*' saltutil.sync_beacons saltenv=base,dev
    '''
    ret = _sync('beacons', saltenv, extmod_whitelist, extmod_blacklist)
    if refresh:
        refresh_beacons()
    return ret