Query parents and count children

count_children.sh

#cleanup first
curl -XDELETE localhost:9200/test/
echo

#create index
curl -XPUT localhost:9200/test
echo

#create parent type
curl -XPUT localhost:9200/test/test_parent
echo

#put a couple of parents
curl -XPUT localhost:9200/test/test_parent/1 -d '{"foo": "bar"}'
curl -XPUT localhost:9200/test/test_parent/2 -d '{"foo": "baz"}'
curl -XPUT localhost:9200/test/test_parent/3 -d '{"foo": "bar baz"}'
echo

#put the child mapping
curl -XPUT localhost:9200/test/test_child/_mapping -d '{
    "test_child" : {
        "_parent" : {
            "type" : "test_parent"
        }
    }
}'
echo

#put a few children for each parent
for i in {1..3}; do
    curl -XPOST localhost:9200/test/test_child?parent=1 -d '{"foo-child": "bar child"}'
    echo
done
for i in {1..5}; do
    curl -XPOST localhost:9200/test/test_child?parent=2 -d '{"foo-child": "bar child2"}'
    echo
done
for i in {1..8}; do
    curl -XPOST localhost:9200/test/test_child?parent=3 -d '{"foo-child": "bar child3"}'
    echo
done

#refresh
curl -XPOST localhost:9200/test/_refresh
echo

#look for parents that contain "bar"
#and return their number of children
curl -XPOST localhost:9200/test/test_child/_search?pretty=true -d '{
    "query": {
        "has_parent": {
            "parent_type": "test_parent",
            "query": {
                "term": {
                    "foo": "bar"
                }
            }
        }
    },
    "facets": {
        "test_facet": {
            "terms": {
                "field": "_parent"
            }
        }
    }
}'
echo