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Log Events

A log event (modelled by LogEvent) contains information at a point in time and the state of a running system.

Important properties of an event are:

TimestampThe point in time when the event occurred, with microsecond or finer resolution.
LoggerName of the logger that sent the event (e.g. a fully-qualified class name).
LevelAn indication of the severity of the event.
HostName of the host where the event originated: important in distributed systems.
ContextContext where the event occurred, typically thread / coroutine name.
MessageA string message summarising what happened, that might be constructed from a template.
Stack traceDetails about an exception or error, if one is associated with the event.
ItemsA map of useful information current at the time of the event.

Each event also has a unique ID that is printed by the internal logger for diagnostic purposes.