{
  "size": 0,
  "query": {
    "bool": {
      "filter": {
        "bool": {
           "must": [
            {"exists": {"field": "from_geo_city_id"}},
            {"exists": {"field": "to_geo_city_id"}},
            {"exists": {"field": "from_country"}},
            {"exists": {"field": "to_country"}},
            {"term": {"type": "route"}}
          ]
        }
      }
    }
  },
  "aggs": {
    "orders_count": {
      "terms": {
        "field": "city_from_to",
        "order": {
          "_count": "desc"
        }
      },
      "aggs": {
        "order_data": {
          "top_hits": {
            "size": 1,
            "_source": {
              "include": [
                "data"
              ]
            }
          }
        }
      }
    }
  }
}