Monitoring kibana stats fails with illegal_argument_exception

[rudolf]

On the 7.12 branch I see the following failures and no kibana stats:

│ proc [kibana] [{"index":{"_type":"kibana_stats"}},{"kibana":{"uuid":"5b2de169-2785-441b-ae8c-186a1936b17d","name":"rudolf-elastic-mbp.lan","index":".kibana","host":"localhost","transport_address":"localhost:5620","version":"7.12.1","snapshot":false,"status":"green"},"os":{"platform":"darwin","platformRelease":"darwin-20.3.0","load":{"1m":13.26806640625,"5m":11.8037109375,"15m":10.20751953125},"memory":{"total_in_bytes":34359738368,"free_in_bytes":732053504,"used_in_bytes":33627684864},"uptime_in_millis":13819000},"response_times":{"average":0,"max":0},"concurrent_connections":0,"process":{"memory":{"heap":{"total_in_bytes":743845888,"used_in_bytes":601313984,"size_limit":4345298944},"resident_set_size_in_bytes":940933120},"event_loop_delay":135.89827999845147,"uptime_in_millis":55719.543128},"requests":{"disconnects":0,"total":0},"timestamp":"2021-04-13T11:14:25.630Z"},{"index":{"_type":"kibana_settings"}},{"kibana":{"uuid":"5b2de169-2785-441b-ae8c-186a1936b17d","name":"rudolf-elastic-mbp.lan","index":".kibana","host":"localhost","locale":"en","port":"5620","transport_address":"localhost:5620","version":"7.12.1","snapshot":false,"status":"green"},"xpack":{"default_admin_email":"test@example.com"}}] [illegal_argument_exception]: The bulk request must be terminated by a newline [\n]
     │ proc [kibana]   log   [13:14:25.893] [warning][kibana-monitoring][monitoring][monitoring][plugins] ResponseError: illegal_argument_exception

Caused by elastic/elasticsearch#71629

[elasticmachine]

Pinging @elastic/kibana-core (Team:Core)

[rudolf]

Seems like this is an upstream bug in elasticsearch-js because of a bug in the Api spec from Elasticsearch

[afharo]

Closing this issue as solved via elasticsearch-js client update.