gistfile1.txt

curl -XGET "http://localhost:9200/installs/install/_search?search_type=count&pretty=1" -d'
{
    "aggs": {
        "last_day" : {
            "filter" : { 
                "range" : { 
                    "_timestamp" : {
                        "gt" : "now-1d"
                    }
                }
            },
            "aggs" : {
                "instanceId_count" : {
                    "cardinality" : { "field" : "instanceId" }
                }
            }
        }
    }
}'