docs: def _replication_request(command, host=None, core_name=None, params=None):
      '''
      PRIVATE METHOD
      Performs the requested replication command and returns a dictionary with
      success, errors and data as keys. The data object will contain the JSON
      response.
  
      command : str
          The replication command to execute.
      host : str (None)
          The solr host to query. __opts__['host'] is default
      core_name: str (None)
          The name of the solr core if using cores. Leave this blank if you are
          not using cores or if you want to check all cores.
      params : list<str> ([])
          Any additional parameters you want to send. Should be a lsit of
          strings in name=value format. e.g. ['name=value']
  
      Return: dict<str, obj>::
  
          {'success':boolean, 'data':dict, 'errors':list, 'warnings':list}
      '''
      params = [] if params is None else params
      extra = ["command={0}".format(command)] + params
      url = _format_url('replication', host=host, core_name=core_name,
                        extra=extra)
      return _http_request(url)