NewReporter creates a new reporter with provided set of Backends.

EventSubTypeConfig is an event indicating application config related event.

EventSubTypeFailed is an event type indicating application is failed.

EventSubTypeInProgress is an event type indicating application is in progress.

EventSubTypeRunning is an event indicating application running related event.

EventSubTypeStarting is an event type indicating application is starting.

EventSubTypeStopped is an event type indicating application is stopped.

EventSubTypeStopping is an event type indicating application is stopping.

EventSubTypeUpdating is an event type indicating update process in progress.

EventTypeActionResult is an record type describing applications result of an action.

EventTypeError is an record type describing application error.

EventTypeState is an record type describing application state change.

Reporter uses multiple backends which needs to be non-blocking to report various events.

Backend defines a actual implementation of reporting.

Event is a reported event.