mdssvc: fix filtering by share path prefix and restrict default fields
This addresses two issues in mdssvc:
- The client Spotlight search is per share and mdssvc maps this to a specific Elasticsearch filter based on the absolute path prefix of the smb.conf share. The way this is currently implemented has two flaws: the filter is not anchored at the beginning at the string and it doesn't correctly differentiate between /foo/bar and /foo/bar2 as the filter used is /foo/bar which matches both. To get filter behaviour similar to a regex "^" anchor, we have to use a prefix filter and ensure the filter path has a trailing slash.
- mdssvc maps the Spotlight wildcard attribute match query ("*") to also search in all attributes in ES which might run into an ES limit if more attributes are available then a configurable maximum. As a better sensible default when mapping from Spotlight "*", we now use a confiruble list of fields which defaults to
["file.filename", "content"].
Edited by Ralph Böhme