make `SearchResult`, `Document` and `AggregationResult` classes more developer friendly

[tgrall]

• SearchResult
• Document
• AggregationResult

We should improve the SearchResult and Document class more developer friendly, it could simply be a different serialization of the document.

Using proper name/value object/map, instead of a list of k/v.

Note: this is just capture as a possible improvement, more thinking is needed, but the idea would be to reduce the code when processing the result.

For example a SearchResult should be represented by a JSON class like this one:

{
   "totalResults":2,
   "docs":[
      {
         "meta":{
            "score":1,
            "id":"movie:1141"
         },
         "body":{
            "ibmdb_id":"tt0113277",
            "plot":"A group of professional ... heist.",
            "genre":"Drama",
            "release_year":"1995",
            "rating":"8.2",
            "votes":"560687",
            "title":"Heat",
            "poster":"https://m..._.jpg"
         }
      },
      {
         "meta":{
            "score":1,
            "id":"movie:818"
         },
         "body":{
            "ibmdb_id":"tt0112617",
            "plot":"A lifeguard bets he can be true to just one woman.",
            "genre":"Comedy",
            "release_year":"1995",
            "rating":"5.4",
            "votes":"32",
            "title":"California Heat",
            "poster":"N/A"
         }
      }
   ]
}

Instead of:

{
   "totalResults":2,
   "docs":[
      {
         "id":"movie:1141",
         "score":1,
         "payload":null,
         "properties":[
            {
               "ibmdb_id":"tt0113277"
            },
            {
               "plot":"A group of professional...heist."
            },
            {
               "genre":"Drama"
            },
            {
               "release_year":"1995"
            },
            {
               "rating":"8.2"
            },
            {
               "votes":"560687"
            },
            {
               "title":"Heat"
            },
            {
               "poster":"https://m.med..._.jpg"
            }
         ]
      },
      {
         "id":"movie:818",
         "score":1,
         "payload":null,
         "properties":[
            {
               "ibmdb_id":"tt0112617"
            },
            {
               "plot":"A lifeguard bets he can be true to just one woman."
            },
            {
               "genre":"Comedy"
            },
            {
               "release_year":"1995"
            },
            {
               "rating":"5.4"
            },
            {
               "votes":"32"
            },
            {
               "title":"California Heat"
            },
            {
               "poster":"N/A"
            }
         ]
      }
   ]
}

Possible solution:

        List<Map<String, Object>> docsToReturn = new ArrayList<>();
        List<Document> docs =  queryResult.docs;

        for (Document doc :docs) {

            Map<String,Object> props = new HashMap<>();
            Map<String,Object> meta = new HashMap<>();
            meta.put("id", doc.getId());
            meta.put("score", doc.getScore());
            doc.getProperties().forEach( e -> {
                props.put( e.getKey(), e.getValue() );
            });

            Map<String,Object> docMeta = new HashMap<>();
            docMeta.put("meta",meta);
            docMeta.put("body",props);
            docsToReturn.add(docMeta);
        }