How to do multiplication on a field like sum function do?

[DeeeFOX]

As title said, how to do multiplication on a field like sum function do like:

POST tsdb_alias/_search?routing=metric_name1
{
  "query": {
    "bool": {
      "filter": [
        {
          "term": {
            "metric": "metric_name1"
          }
        },
        {
          "term": {
            "t.key1": "val1"
          }
        },
        {
          "range": {
            "@timestamp": {
              "gte": "2020-01-01",
              "lte": "2020-01-02"
            }
          }
        }
      ]
    }
  },
  "aggs": {
    "ts": {
      "date_histogram": {
        "field": "@timestamp",
        "interval": "1h"
      },
      "aggs": {
        "res": {
          "multiplier": {
            "field": "f.name1"
          }
        }
      }
    }
  },
  "size": 0
}

In our use case, we use es as tsdb that described in

my other topic

and data we store are look like:

{
	"metric": "metric_name",
	"@timestamp": "2020-01-01T01:01:01",
	"t": {
		"key1": "val1",
		"key2": "val2"
	},
	"f": {
		"name1": 1.2,
		"name2": 2.3
	}
}