Elasticsearch query: combine nested array of objects into one array - arrays

Question

Using Elasticsearch I am trying to combine a nested array of objects into one array.
This is what my data looks like:
GET invoices/_search
{
"hits": [
{
"_index": "invoices",
"_id": "1234",
"_score": 1.0,
"_source": {
"id": 1234,
"status": "unpaid",
"total": 15.35,
"payments": [
{
"id": 1981,
"amount": 10,
"date": "2022-02-09T13:00:00+01:00"
},
{
"id": 1982,
"amount": 5.35,
"date": "2022-02-09T13:35:00+01:00"
}
]
}
},
# ... More hits
]
}
I want to only get the payments array of each hit combined into one array, so that it returns something like this:
{
"payments": [
{
"id": 1981,
"amount": 10,
"date": "2022-02-09T13:00:00+01:00"
},
{
"id": 1982,
"amount": 5.35,
"date": "2022-02-09T13:35:00+01:00"
},
{
"id": 5658,
"amount": 3,
"date": "2021-12-19T13:00:00+01:00"
}
]
}
I tried to get this result using nested queries but could not figure it out, the query I used is:
# Query I used:
GET invoices/_search
{
"_source": ["payments"],
"query": {
"nested": {
"path": "payments",
"query": {
"bool": {
"must": [
{
"exists": {
"field": "payments.id"
}
}
]
}
}
}
}
}
# Result:
{
"hits": [
{
"_index": "invoices",
"_id": "545960",
"_score": 1.0,
"_source": {
"payments": [
{
"date": "2022-01-22T15:38:15+01:00",
"amount": 374.5,
"id": 320320
},
{
"date": "2022-01-22T15:30:03+01:00",
"amount": 160.5,
"id": 320316
}
]
}
},
{
"_index": "invoices",
"_id": "545961",
"_score": 1.0,
"_source": {
"payments": [
{
"date": "2022-01-22T15:38:15+01:00",
"amount": 12,
"id": 320350
},
{
"date": "2022-01-22T15:30:03+01:00",
"amount": 60.65,
"id": 320379
}
]
}
}
]
}
The result returns only the payments array but divided over multiple hits. How can I combine those arrays?