Elasticsearch: When doing an "inner_hit" on nested documents, return all fields of matched offset in the hierarchy - elasticsearch

Question

Mapping for document:
{
"mappings": {
"properties": {
"client_classes": {
"type": "nested",
"properties": {
"members": {
"type": "nested",
"properties": {
"phone_nos": {
"type": "nested"
}
}
}
}
}
}
}
}
Data in Document:
{
"client_name":"client1",
"client_classes":[
{
"class_name":"class1",
"members":[
{
"name":"name1",
"phone_nos":[
{
"ext":"91",
"number":"99119XXXX"
},
{
"ext":"04",
"number":"99885XXXX"
}
]
},
{
"name":"name2",
"phone_nos":[
{
"ext":"03",
"number":"99887XXXX"
}
]
}
]
}
]
}
I query for "number" with value "99119XXXX"
{
"query":{
"nested":{
"path":"client_classes.members.phone_nos",
"query":{
"match":{
"client_classes.members.phone_nos.number":"99119XXXX"
}
},
"inner_hits":{}
}
}
}
Result from inner hits:
"inner_hits":{
"client_classes.members.phone_nos":{
"hits":{
"total":{
"value":1,
"relation":"eq"
},
"max_score":0.9808291,
"hits":[
{
"_index":"clients",
"_type":"_doc",
"_id":"1",
"_nested":{
"field":"client_classes",
"offset":0,
"_nested":{
"field":"members",
"offset":0,
"_nested":{
"field":"phone_nos",
"offset":0
}
}
},
"_score":0.9808291,
"_source":{
"ext":"91",
"number":"99119XXXX"
}
}
]
}
}
}
I get the desired matched result hierarchy of all the nested objects, in the inner hit, but I only receive the "offset" value and "field" from these objects. I need the full object of the corresponding offset.
Something like this:
{
"client_name":"client1",
"client_classes":[
{
"class_name":"class1",
"members":[
{
"name":"name1",
"phone_nos":[
{
"ext":"91",
"number":"99119XXXX"
}
]
}
]
}
]
}
I understand that with inner_hit I also get the complete root document, from where I can use the offset values from the innerhit object. But fetching the entire root document could be expensive for our memory, so I only need the result I have shared above.
Is there any such possibility as of now?
I am using elasticsearch 7.7
UPDATE: Added Mapping, result and a slight fix in document

Answer 1

Yes, just add "_source": false at the top-level and you'll only get the nested inner hits
{
"_source": false, <--- add this
"query":{
"nested":{
"path":"client_classes.members.phone_nos",
"query":{
"match":{
"client_classes.members.phone_nos.number":"99119XXXX"
}
},
"inner_hits":{}
}
}
}