reference: https://github.com/uber-go/zap/blob/v1.27.0/zapcore/level.go#L34 */.

DPanicLevel logs are particularly important errors.

ErrorLevel logs are high-priority.

FatalLevel logs a message, then calls os.Exit(1).

InfoLevel is the default logging priority.

PanicLevel logs a message, then panics.

WarnLevel logs are more important than Info, but don't need individual human review.