Cleanup does something windup for logger, like closing, flushing, etc.

CreateLoggerAsLocalFile setups the logger by local file path.

Debugf logs messages at DEBUG level.

Error prints err if it's not nil.

Errorf logs messages at ERROR level.

Fatalf logs messages at FATAL level.

GetDefaultLogger returns the default logger.

Infof logs messages at INFO level.

LogLevel tells what the default logging level is.

Warnf logs messages at WARN level.

DebugLevel logs are typically voluminous, and are usually disabled in production.

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.

Logger is used for logging formatted messages.

Level is the alias of zapcore.Level.