Defining Grandparents aggregations, getting a NullPointer

[paolociccarese]

I am using Elasticsearch 1.4.4.
I am defining a parent-child index with three levels (grandparents) following the instructions in the document: https://www.elastic.co/guide/en/elasticsearch/guide/current/grandparents.html
My structure is Continent -> Country -> Region

MAPPING

I create an index with the following mapping:

curl -XPOST 'localhost:9200/geo' -d'
{
  "mappings": {
    "continent": {},
    "country": {
    "_parent": {
      "type": "continent" 
    }
  },
  "region": {
    "_parent": {
     "type": "country" 
  }
}
}
}' 

INDEXING

I index three entities:

curl -XPOST 'localhost:9200/geo/continent/europe' -d'
{
  "name":"Europe"
}'

curl -XPOST 'localhost:9200/geo/country/italy?parent=europe' -d'
{
  "name":"Italy"
}'

curl -XPOST 'localhost:9200/geo/region/lombardy?parent=italy&routing=europe' -d'
{
  "name":"Lombardia"
}'

QUERY THAT WORKS

If I query and aggregate according to the document everything works fine:

curl -XGET 'localhost:9200/geo/continent/_search?pretty=true' -d '
{
"query": {
    "has_child": {
        "type": "country",
        "query": {
            "has_child": {
            "type": "region",
                "query": {
                    "match": {
                        "name": "Lombardia"
                    }
                }
            }
        }
    }
},
"aggs": {
    "country": {
        "terms": { 
            "field": "name"
        },
        "aggs": {
            "countries": {
                "children": {
                    "type": "country"
                },
                "aggs": {
                    "country_names" : {
                        "terms" :  {
                            "field" : "country.name"
                        }
                    }                   
                }
            }
        }
    }
}
}'

QUERY THAT DOES NOT WORK

However, if I try with multi-level aggregations like in:

curl -XGET 'localhost:9200/geo/continent/_search?pretty=true' -d '
{
"query": {
    "has_child": {
        "type": "country",
        "query": {
            "has_child": {
            "type": "region",
                "query": {
                    "match": {
                        "name": "Lombardia"
                    }
                }
            }
        }
    }
},
"aggs": {
    "continent_names": {
        "terms": { 
            "field": "name"
        },
        "aggs": {
            "countries": {
                "children": {
                    "type": "country"
                },                  
                "aggs": {
                    "regions": {
                        "children": {
                            "type": "region"
                        }, 
                        "aggs": {
                            "region_names" : {
                                "terms" :  {
                                    "field" : "region.name"
                                }
                            }
                        }
                    }
                }
            }
        }
    }
}
}'

I get back the following
{

"error" : "SearchPhaseExecutionException[Failed to execute phase [query], all shards failed; shardFailures {[b5CbW5byQdSSW-rIwta0rA][geo][0]: QueryPhaseExecutionException[[geo][0]: query[filtered(child_filtercountry/continent)->cache(_type:continent)],from[0],size[10]: Query Failed [Failed to execute main query]]; nested: NullPointerException; }{[b5CbW5byQdSSW-rIwta0rA][geo][1]: QueryPhaseExecutionException[[geo][1]: query[filtered(child_filtercountry/continent)->cache(_type:continent)],from[0],size[10]: Query Failed [Failed to execute main query]]; nested: NullPointerException; }{[b5CbW5byQdSSW-rIwta0rA][geo][2]: QueryPhaseExecutionException[[geo][2]: query[filtered(child_filtercountry/continent)->cache(_type:continent)],from[0],size[10]: Query Failed [Failed to execute main query]]; nested: NullPointerException; }{[b5CbW5byQdSSW-rIwta0rA][geo][3]: QueryPhaseExecutionException[[geo][3]: query[filtered(child_filtercountry/continent)->cache(_type:continent)],from[0],size[10]: Query Failed [Failed to execute main query]]; nested: NullPointerException; }{[b5CbW5byQdSSW-rIwta0rA][geo][4]: QueryPhaseExecutionException[[geo][4]: query[filtered(child_filtercountry/continent)->cache(_type:continent)],from[0],size[10]: Query Failed [Failed to execute main query]]; nested: NullPointerException; }]",

"status" : 500

}

The 'grandparents' document says: "Querying and aggregating across generations works, as long as you step through each generation."

How do I get the last query and aggregation to work across all three levels of the index?

What am I missing?

Thank you,
Paolo

[javanna]

this seems like a bug, @martijnvg can you have a look please?

[martijnvg]

@paolociccarese @javanna Sorry, I missed this! I opened PR #10263 for this bug.