Full Text Index with Lucene on Entire Record?

Is it possible to index an entire schema-less record (i.e. the JSON representation) using a Lucene index? If not, is it possible to index an embedded field so that it is possible to query the JSON stored in that field in a “property:value aware” way?

My use-case is that I need to be able to search for arbitrary “fields”, so I won’t be able to create indexes on individual fields because I won’t know what they are in advance (and they will change on a per record basis). I know I can index simple text in a field with Lucene and get a full text index on the contents, but just indexing a JSON document doesn’t allow me to differentiate between property names and values during a search.