ELASTICSEARCH - Ordering aggregation by date on nested field - elasticsearch

Question

I am developing a query where I count how many unique "cp" the most recent document contains.
The json is made up of several nested fields.
I am having trouble showing only the json value with the most recent date when I add to a json with nested fields.
I have done nested aggregations, and finally I have used top_hits filter to sort in descending order, and it returns me the last one through the size.
But still it is returning all the documents with different dates.
JSON:
"data" : [
{
"addresses" : [
{
"cp" : "33.33.33",
"services" : [
{
"field1" : "true",
"field2" : "1234",
}
]
}
],
}
],
"created_at" : "2020-09-03 14:39:01",
"#timestamp" : "2020-09-04T05:53:22.341661Z",
}
},
QUERY:
{"size": 0,
"aggs": {
"nested": {
"nested": {
"path": "data.addresses"
},
"aggs": {
"nested": {
"nested": {
"path": "data.addresses.services"
},
"aggs": {
"filter": {
"filter": {
"term": {
"data.addresses.services.field1.keyword": "true"
}
},
"aggs": {
"unique": {
"cardinality": {
"field": "data.addresses.services.field2.keyword"
}
},
"range":{
"top_hits": {
"size": 1,
"sort": [
{"created_at.keyword": {"order": "desc"}}]
}
}
}
}
}
}
}
}
}
I have tried sorting by the predefined field "created_at" or with #timestamp, but the result is the same.
Any advice that can help me to solve my problem?

Answer 1

For this case the solution is to add
"order": {
"_key": "desc":
instead of top_hits.
QUERY
{"size": 0,
"aggs": {
"filtrofecha": {
"terms": {
"field": "created_at.keyword",
"order": {
"_key": "desc"
},
"size": 1
},
"aggs": {
"nested": {
"nested": {
"path": "data.addresses"
},
"aggs": {
"nested": {
"nested": {
"path": "data.addresses.services"
},
"aggs": {
"filter": {
"filter": {
"term": {
"data.addresses.services.field1.keyword": "true"
}
},
"aggs": {
"unique": {
"cardinality": {
"field": "data.addresses.services.field2.keyword"
}
}
}
}
}
}
}
}
}
}
}