APOC Elasticsearch query format - elasticsearch

Question

I am using Neo4j 4.0.3, Elasticsearch 6.8.3 and APOC.
I want to run an Elasticsearch aggregation query through Neo4J using the APOC Elasticsearch procedure.
The query is defined in the request body and works on Elasticsearch but I'm not sure how to construct the query parameter through the procedure. In Elasticsearch I can pass the request body as a source parameter (with a source content type of JSON).
To demonstrate, I've tried to get a simple query working.
This works in Elasticsearch:
GET http://localhost:9200/trends/trend/_search?source={"query": {"match" : {"type" : "ENTITY"}}}&source_content_type=application/json
but when I try this through the ES procedure:
CALL apoc.es.query('elasticsearch:9200', 'trends', 'trend', 'source={"query":{"match":{"type":"ENTITY"}}}&source_content_type=application/json', null)
Neo4J gives the following error:
Failed to invoke procedure `apoc.es.query`: Caused by: java.net.URISyntaxException: Illegal character in query at index 54: http://elasticsearch:9200/trends/trend/_search?source={"query":{"match":{"type":%22ENTITY%22%7D%7D%7D````
What do I need to do to pass the query correctly?

Answer 1

Got it to work, I overlooked the payload parameter. So the APOC call was this:
CALL apoc.es.query('elasticsearch:9200', 'trends', 'trend', null, '{"query":{"match":{"type":"ENTITY"}}}')
Alternatively I could have passed the query as a Map
CALL apoc.es.query('elasticsearch:9200', 'trends', 'trend', apoc.map.fromPairs([
["source_content_type", "application/json"],
["source", '{"query":{"match":{"type":"ENTITY"}}}']
]), null)

Answer 2

If you want to use a scroll ID and also a payload to specify the query, something like this works:
CALL apoc.es.query('localhost','indexName','doc','scroll=1m','{
"query":{
"query_string":{
"query": "name:somebody AND date:[now-30d TO now]"
}
},
"size":"1000"
}') yield value
with value._scroll_id as scrollId, value.hits.hits as hits
// Do something with hits
UNWIND hits as hit
return hit
This format makes editing the query easier: I've found inconsistent results and URL escaping rules when putting the query in a string in the fourth parameter position.
See https://www.elastic.co/guide/en/elasticsearch/reference/current/search-request-body.html and https://neo4j.com/docs/labs/apoc/4.0/database-integration/elasticsearch/