Boost issue

index metadata

# note that the properties are empty

{
  state: open,
  settings: {
    index.number_of_replicas: 0,
    index.number_of_shards: 1,
    index.version.created: 200051
  },
  mappings: {
    test: {
      _boost: {
        null_value: 1,
        name: Boost
      },
      properties: {
        
      }
    }
  },
  aliases: [
    
  ]
}

index populataion

curl -XPOST localhost:9200/test -d '{
    "settings" : {
        "number_of_shards" : 1,  	
	      "number_of_replicas" : 0
    },
    "mappings" : {
        "test" : {
            "_boost": {"name": "Boost", "null_value": 1.0},
            "properties" : {
                "Boost" : { "type" : "float", "index": "not_analyzed" }
            }
        }
    }
}'

curl -XPUT http://localhost:9200/test/test/1 -d '{
    "Boost": "25.0"
}'

curl -XPUT http://localhost:9200/test/test/2 -d '{
    "Boost": "0.5"
}'

curl -XPUT http://localhost:9200/test/test/3 -d '{
    "Boost": "0.5"
}'

curl -XPUT http://localhost:9200/test/test/4 -d '{
    "Boost": "14.1"
}'

search

curl -XGET http://localhost:9200/test/test/_search?pretty=true -d '
{
  "from" : 0,
  "size" : 10,
  "query" : {
    "match_all" : { }
  },
  "sort" : [ {  
  "Boost" : {
      "order" : "desc"
    }
  } ]
}
'

search response

{
  "took" : 2,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "failed" : 0
  },
  "hits" : {
    "total" : 4,
    "max_score" : null,
    "hits" : [ {
      "_index" : "test",
      "_type" : "test",
      "_id" : "1",
      "_score" : null, "_source" : {
    "Boost": "25.0"
},
      "sort" : [ 0.0 ]
    }, {
      "_index" : "test",
      "_type" : "test",
      "_id" : "2",
      "_score" : null, "_source" : {
    "Boost": "0.5"
},
      "sort" : [ 0.0 ]
    }, {
      "_index" : "test",
      "_type" : "test",
      "_id" : "3",
      "_score" : null, "_source" : {
    "Boost": "0.5"
},
      "sort" : [ 0.0 ]
    }, {
      "_index" : "test",
      "_type" : "test",
      "_id" : "4",
      "_score" : null, "_source" : {
    "Boost": "14.1"
},
      "sort" : [ 0.0 ]
    } ]
  }
}