/*
$params['index'] = (list) A comma-separated list of index names to search; use `_all` or empty string to perform the operation on all indices (Required)
$params['type'] = DEPRECATED (list) A comma-separated list of document types to search; leave empty to perform the operation on all types
$params['routing'] = (string) Specific routing value
$params['timeout'] = (time) Explicit operation timeout
$params['body'] = (array) Graph Query DSL
*/