elasticsearch nested aggregate based on attribute and get custom value based on a formula in every bucket -

i have dataset of event actions:

 {"person" : "person1", "event" : "e1", "action" : "like"}  {"person" : "person2", "event" : "e1", "action" : "dislike"}  {"person" : "person1", "event" : "e1", "action" : "share"}  {"person" : "person1", "event" : "e1", "action" : "rating"}  {"person" : "person1", "event" : "e2", "action" : "rating"} 

can aggregate based on event , on bucket, based on weighted metrics on actions single custom value bucket?

i have done nested aggregation:

{  "size": 0,   "aggs": {     "all_events": {       "terms": {         "field": "event.keyword"       },       "aggs": {         "overall_ratings": {           "terms": {             "field": "action.keyword"           }         }       }     }   } 

}

so result:

• e1 -> - 10, dislike: 4, share: 8
• e2 -> - 30, dislike: 0, share: 2

but want apply formula get

• e1 -> (like*5) + (dislike* -3) + (share*2) = (10*5)+(4*-3)+(8*2) = 50-12+16= 54

i want:

• e1 -> 54
• e2 -> 154

yes, possible, can build quite complicated formulas aggregations. use scripted metric aggregations.

in example - data provied - result should be:

e1 -> (1*5) + (1*-3) + (1*2) = 5 - 3 + 2 = 4 e2 -> 0 

the aggregating query have be:

{  "size": 0,   "aggs": {     "all_events": {       "terms": {         "field": "event.keyword"       },       "aggs": {         "overall_ratings": {           "scripted_metric": {             "init_script": "params._agg.transactions = [];",             "map_script": "if (doc.action.value == 'like') params._agg.transactions.add(5); if (doc.action.value == 'dislike') params._agg.transactions.add(-3); if (doc.action.value == 'share') params._agg.transactions.add(2);",             "combine_script" : "int total = 0; (t in params._agg.transactions) { total += t; } return total;",             "reduce_script" : "int total = 0; (a in params._aggs) { total += a; } return total;"           }         }       }     }   } } 

and query gave me following result:

{     "took": 4,     "timed_out": false,     "_shards": {         "total": 5,         "successful": 5,         "failed": 0     },     "hits": {         "total": 5,         "max_score": 0,         "hits": []     },     "aggregations": {         "all_events": {             "doc_count_error_upper_bound": 0,             "sum_other_doc_count": 0,             "buckets": [                 {                     "key": "e1",                     "doc_count": 4,                     "overall_ratings": {                         "value": 4                     }                 },                 {                     "key": "e2",                     "doc_count": 1,                     "overall_ratings": {                         "value": 0                     }                 }             ]         }     } } 

one importanat thing - may necessary have action field set in mapping "fielddata": true:

"action": {     "type": "text",     ...,     "fielddata": true } 

otherwise you'll exception "fielddata disabled on text fields default...."