Sort parent type based on one field within an array of nested Object in elasticsearch - elasticsearch

Question

I have below mapping in my index:
{
"testIndex": {
"mappings": {
"type1": {
"properties": {
"text": {
"type": "string"
},
"time_views": {
"properties": {
"timestamp": {
"type": "long"
},
"views": {
"type": "integer"
}
}
}
}
}
}
}
}
"time_views" actually is an array, but inner attributes not array.
I want to sort my type1 records based on maximum value of "views" attribute of each type1 record. I read elasticsearch sort documentation, it's have solution for use cases that sorting is based on field (single or array) of single nested object. but what I want is different. I want pick maximum value of "views" for each document and sort the documents based on these values
I made this json query
{
"size": 10,
"query": {
"range": {
"timeStamp": {
"gte": 1468852617347,
"lte": 1468939017347
}
}
},
"from": 0,
"sort": [
{
"time_views.views": {
"mode": "max",
"nested_path": "time_views",
"order": "desc"
}
}
]
}
but I got this error
{
"error": {
"phase": "query",
"failed_shards": [
{
"node": "n4rxRCOuSBaGT5xZoa0bHQ",
"reason": {
"reason": "[nested] nested object under path [time_views] is not of nested type",
"col": 136,
"line": 1,
"index": "data",
"type": "query_parsing_exception"
},
"index": "data",
"shard": 0
}
],
"reason": "all shards failed",
"grouped": true,
"type": "search_phase_execution_exception",
"root_cause": [
{
"reason": "[nested] nested object under path [time_views] is not of nested type",
"col": 136,
"line": 1,
"index": "data",
"type": "query_parsing_exception"
}
]
},
"status": 400
}
as I mentioned above time_views is an array and I guess this error is because of that.
even I can't use sorting based on array field feature, because "time_views" is not a primitive type.
I think my last chance is write a custom sorting by scripting, but I don't know how.
please tell me my mistake if it's possible to achieve to what I'm want, otherwise give me a simple script sample.
tnx :)

Answer 1

The error message does a lot to explain what is wrong with the query. Actually, the problem is with the mapping. And I think you intended on using nested fields, since you are using nested queries.
You just need to make your time_views field as nested:
"mappings": {
"type1": {
"properties": {
"text": {
"type": "string"
},
"time_views": {
"type": "nested",
"properties": {
"timestamp": {
"type": "long"
},
"views": {
"type": "integer"
}
}
}
}
}
}