logger.go

// SPDX-License-Identifier: BSD-3-Clause
//
// Authors: Alexander Jung <alex@unikraft.io>
//
// Copyright (c) 2022, Unikraft GmbH.  All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
// 1. Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright
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//    this software without specific prior written permission.
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// SOFTWARE.

package log

import "io"

const Format = "2006-01-02 15:04:05"

type Logger interface {
	Trace(a ...interface{})
	Tracef(format string, a ...interface{})
	Debug(a ...interface{})
	Debugf(format string, a ...interface{})
	Info(a ...interface{})
	Infof(format string, a ...interface{})
	Warn(a ...interface{})
	Warnf(format string, a ...interface{})
	Warning(a ...interface{})
	Warningf(format string, a ...interface{})
	Error(a ...interface{})
	Errorf(format string, a ...interface{})
	Fatal(a ...interface{})
	Fatalf(format string, a ...interface{})
	SetOutput(w io.Writer)

	// Clone provides a semantic copy of the current instance of the Logger such
	// that it can be used independently but with the same configuration.  This
	// may useful for sub-processes.
	Clone() Logger

	// Output returns the io.Writer used in the Logger's underlying implementation
	Output() io.Writer

	// Level returns the current log level
	Level() string
}