Druid generates alerts on getting into unexpected situations.
Alerts are emitted as JSON objects to a runtime log file or over HTTP (to a service such as Apache Kafka). Alert emission is disabled by default.
All Druid alerts share a common set of fields:
timestamp- the time the alert was created
service- the service name that emitted the alert
host- the host name that emitted the alert
severity- severity of the alert e.g. anomaly, component-failure, service-failure etc.
description- a description of the alert
data- if there was an exception then a JSON object with fields