logger

Documentation

Overview

Package logger implements a multi-output leveled logger.

Other packages use tagged logger to send log messages to shared (process-wide) logging engine. The shared logging engine dispatches to multiple log systems. The log level can be set separately per log system.

Logging is asynchronous and does not block the caller. Message formatting is performed by the caller goroutine to avoid incorrect logging of mutable state.

Index

• func AddLogSystem(sys LogSystem)
• func Flush()
• func Reset()
• type LogLevel
• type LogSystem
  • func NewStdLogSystem(writer io.Writer, flags int, level LogLevel) LogSystem
• type Logger
  • func NewLogger(tag string) *Logger
  • func (logger *Logger) DebugDetailf(format string, v ...interface{})
  • func (logger *Logger) DebugDetailln(v ...interface{})
  • func (logger *Logger) Debugf(format string, v ...interface{})
  • func (logger *Logger) Debugln(v ...interface{})
  • func (logger *Logger) Errorf(format string, v ...interface{})
  • func (logger *Logger) Errorln(v ...interface{})
  • func (logger *Logger) Fatalf(format string, v ...interface{})
  • func (logger *Logger) Fatalln(v ...interface{})
  • func (logger *Logger) Infof(format string, v ...interface{})
  • func (logger *Logger) Infoln(v ...interface{})
  • func (logger *Logger) Warnf(format string, v ...interface{})
  • func (logger *Logger) Warnln(v ...interface{})

Examples

• LogSystem
• Logger

Functions

func AddLogSystem

func AddLogSystem(sys LogSystem)

AddLogSystem starts printing messages to the given LogSystem.

func Flush

func Flush()

Flush waits until all current log messages have been dispatched to the active log systems.

func Reset

func Reset()

Reset removes all active log systems. It blocks until all current messages have been delivered.

Types

type LogLevel

type LogLevel uint8

const (
	// Standard log levels
	Silence LogLevel = iota
	ErrorLevel
	WarnLevel
	InfoLevel
	DebugLevel
	DebugDetailLevel
)

type LogSystem

type LogSystem interface {
	GetLogLevel() LogLevel
	SetLogLevel(i LogLevel)
	LogPrint(LogLevel, string)
}

LogSystem is implemented by log output devices. All methods can be called concurrently from multiple goroutines.

Example

filename := "test.log"
file, _ := os.OpenFile(filename, os.O_RDWR|os.O_CREATE, os.ModePerm)
fileLog := NewStdLogSystem(file, 0, WarnLevel)
AddLogSystem(fileLog)

stdoutLog := NewStdLogSystem(os.Stdout, 0, WarnLevel)
AddLogSystem(stdoutLog)

NewLogger("TAG").Warnln("reactor meltdown") // writes to both logs

func NewStdLogSystem

func NewStdLogSystem(writer io.Writer, flags int, level LogLevel) LogSystem

NewStdLogSystem creates a LogSystem that prints to the given writer. The flag values are defined package log.

type Logger

type Logger struct {
	// contains filtered or unexported fields
}

A Logger prints messages prefixed by a given tag. It provides named Printf and Println style methods for all loglevels. Each ethereum component should have its own logger with a unique prefix.

Example

logger := NewLogger("TAG")
logger.Infoln("so awesome")            // prints [TAG] so awesome
logger.Infof("this %q is raw", "coin") // prints [TAG] this "coin" is raw

func NewLogger

func NewLogger(tag string) *Logger

func (*Logger) DebugDetailf

func (logger *Logger) DebugDetailf(format string, v ...interface{})

DebugDetailf writes a message with DebugDetailLevel.

func (*Logger) DebugDetailln

func (logger *Logger) DebugDetailln(v ...interface{})

DebugDetailln writes a message with DebugDetailLevel.

func (*Logger) Debugf

func (logger *Logger) Debugf(format string, v ...interface{})

Debugf writes a message with DebugLevel.

func (*Logger) Debugln

func (logger *Logger) Debugln(v ...interface{})

Debugln writes a message with DebugLevel.

func (*Logger) Errorf

func (logger *Logger) Errorf(format string, v ...interface{})

Errorf writes a message with ErrorLevel.

func (*Logger) Errorln

func (logger *Logger) Errorln(v ...interface{})

Errorln writes a message with ErrorLevel.

func (*Logger) Fatalf

func (logger *Logger) Fatalf(format string, v ...interface{})

Fatalf writes a message with ErrorLevel and exits the program.

func (*Logger) Fatalln

func (logger *Logger) Fatalln(v ...interface{})

Fatalln writes a message with ErrorLevel and exits the program.

func (*Logger) Infof

func (logger *Logger) Infof(format string, v ...interface{})

Infof writes a message with InfoLevel.

func (*Logger) Infoln

func (logger *Logger) Infoln(v ...interface{})

Infoln writes a message with InfoLevel.

func (*Logger) Warnf

func (logger *Logger) Warnf(format string, v ...interface{})

Warnf writes a message with WarnLevel.

func (*Logger) Warnln

func (logger *Logger) Warnln(v ...interface{})

Warnln writes a message with WarnLevel.