log

type Level int

type NamedLogger interface {
	// Log is a generic method that will write
	// to named logger and can accept custom
	// logging levels
	Log(lvl Level, msg ...interface{})
	// Logf is just like Log, but with formatting
	Logf(lvl Level, format string, a ...interface{})

	// Debug is a logging method that will write
	// to named logger with DEBUG level
	Debug(msg ...interface{})
	// Debugf is just like Debug, but with formatting
	Debugf(format string, a ...interface{})

	// Info is a logging method that will write
	// to named logger with INFO level
	Info(msg ...interface{})
	// Infof is just like Info, but with formatting
	Infof(format string, a ...interface{})

	// Warn is a logging method that will write
	// to named logger with WARNING level
	Warn(msg ...interface{})
	// Warnf is just like Warn, but with formatting
	Warnf(format string, a ...interface{})

	// Error is a logging method that will write
	// to named logger with ERROR level
	Error(msg ...interface{})
	// Errorf is just like Error, but with formatting
	Errorf(format string, a ...interface{})

	// Fatal is a logging method that will write
	// to named logger with FATAL level and
	// terminate program with exit code 1
	Fatal(msg ...interface{})
	// Fatalf is just like Fatal, but with formatting
	Fatalf(format string, a ...interface{})

	// SetFormat sets logging format for named logger.
	// It takes a string that is processed by text/template
	// with required values in template:
	//
	// {{.Timestamp}} is a Timestamp format for which is set via SetTimeFormat
	// {{.Namespace}} is a namespace of logger, default logger namespace is "main"
	// {{.Level}} is a logging Level for current record
	// {{.Message}} is actual Message contents
	//
	// If passed format cannot be parsed the function panics.
	SetFormat(format string) NamedLogger

	// SetTimeFormat is a method to set timestamp formatting for
	// named logger separately from other loggers.
	// Returns itself for easy chaining.
	SetTimeFormat(format string) NamedLogger

	// SetTimeFormat is a method to set output for
	// named logger separately from other loggers.
	// Returns itself for easy chaining.
	SetOutput(w io.Writer) NamedLogger
}