Order by "_term" in elasticsearch query is deprecated in version 6.0.0

[calixteman]

I made a query with an order inside an aggregation:
'order': { '_key': 'desc' }
and the result was empty.
After reading the docs: https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations-bucket-terms-aggregation.html
I replaced '_key' by '_term' and it's ok, but according to this doc '_term' is deprecated in 6.0.0.
So when your ES will be updated, my query could silently failed and so you should probably add a warning field in the result to explain the deprecation or return an error when keywords are not correct.

[leplatrem]

Thanks for reporting this! I took track of this in kinto-elasticsearch, where we catch ES error and return an empty response...