Nested filter returns 0 doc_count - elasticsearch

Question

For this index and sample data:
PUT job_offers
{
"mappings": {
"properties": {
"location": {
"properties": {
"slug": {
"type": "keyword"
},
"name": {
"type": "keyword"
}
},
"type": "nested"
},
"experience": {
"properties": {
"slug": {
"type": "keyword"
},
"name": {
"type": "keyword"
}
},
"type": "nested"
}
}
}
}
POST job_offers/_doc
{
"title": "Junior Ruby on Rails Developer",
"location": [
{
"slug": "new-york",
"name": "New York"
},
{
"slug": "atlanta",
"name": "Atlanta"
},
{
"slug": "remote",
"name": "Remote"
}
],
"experience": [
{
"slug": "junior",
"name": "Junior"
}
]
}
POST job_offers/_doc
{
"title": "Ruby on Rails Developer",
"location": [
{
"slug": "chicago",
"name": "Chicago"
},
{
"slug": "atlanta",
"name": "Atlanta"
}
],
"experience": [
{
"slug": "senior",
"name": "Senior"
}
]
}
I try to run filter on experience.slug:
GET job_offers/_search
{
"query": {
"nested": {
"path": "location",
"query": {
"terms": {
"location.slug": [
"remote",
"new-york"
]
}
}
}
},
"aggs": {
"filtered_job_offers": {
"global": {},
"aggs": {
"filtered_location": {
"filter": {
"bool": {
"must": [
{
"terms": {
"experience.slug": [
"junior"
]
}
}
]
}
}
}
}
}
}
}
Response for this:
"aggregations" : {
"filtered_job_offers" : {
"doc_count" : 2,
"filtered_location" : {
"doc_count" : 0
}
}
}
Why do I get doc_count: 0 for filtered_location instead of 1? How can I make it work?

Answer 1

You were pretty close! Gotta use a nested query in the aggregations:
...
"aggs": {
"filtered_job_offers": {
"global": {},
"aggs": {
"filtered_location": {
"filter": {
"bool": {
"must": [
{
"nested": { <-----
"path": "experience",
"query": {
"terms": {
"experience.slug": [
"junior"
]
}
}
}
}
]
}
}
}
}
}
}