logging

Documentation

Overview

Package logging implements the logger for the pack CLI.

Package logging defines the minimal interface that loggers must support to be used by client.

Index

• Constants
• func GetWriterForLevel(logger Logger, level Level) io.Writer
• func IsQuiet(logger Logger) bool
• func ScanLinesKeepNewLine(data []byte, atEOF bool) (advance int, token []byte, err error)
• func Tip(l Logger, format string, v ...interface{})
• func WithClock(clock func() time.Time) func(writers *LogWithWriters)
• func WithVerbose() func(writers *LogWithWriters)
• type Level
• type LogWithWriters
  • func NewLogWithWriters(stdout, stderr io.Writer, opts ...func(*LogWithWriters)) *LogWithWriters
  • func (lw *LogWithWriters) HandleLog(e *log.Entry) error
  • func (lw *LogWithWriters) IsVerbose() bool
  • func (lw *LogWithWriters) WantQuiet(f bool)
  • func (lw *LogWithWriters) WantTime(f bool)
  • func (lw *LogWithWriters) WantVerbose(f bool)
  • func (lw *LogWithWriters) Writer() io.Writer
  • func (lw *LogWithWriters) WriterForLevel(level Level) io.Writer
• type Logger
  • func NewSimpleLogger(w io.Writer) Logger
• type PrefixWriter
  • func NewPrefixWriter(w io.Writer, prefix string, opts ...PrefixWriterOption) *PrefixWriter
  • func (w *PrefixWriter) Close() error
  • func (w *PrefixWriter) Write(data []byte) (int, error)
• type PrefixWriterOption
  • func WithReaderFactory(factory func(data []byte) io.Reader) PrefixWriterOption

Constants

const (

	// InvalidFileDescriptor based on https://golang.org/src/os/file_unix.go?s=2183:2210#L57
	InvalidFileDescriptor = ^(uintptr(0))
)

Functions

func GetWriterForLevel

func GetWriterForLevel(logger Logger, level Level) io.Writer

GetWriterForLevel retrieves the appropriate Writer for the log level provided.

See isSelectableWriter

func IsQuiet

func IsQuiet(logger Logger) bool

IsQuiet defines whether a pack logger is set to quiet mode

func ScanLinesKeepNewLine

func ScanLinesKeepNewLine(data []byte, atEOF bool) (advance int, token []byte, err error)

A customized implementation of bufio.ScanLines that preserves new line characters.

func Tip

func Tip(l Logger, format string, v ...interface{})

Tip logs a tip.

func WithClock

func WithClock(clock func() time.Time) func(writers *LogWithWriters)

WithClock is an option used to initialize a LogWithWriters with a given clock function

func WithVerbose

func WithVerbose() func(writers *LogWithWriters)

WithVerbose is an option used to initialize a LogWithWriters with Verbose turned on

Types

type Level

type Level int

const (
	DebugLevel Level = iota
	InfoLevel
	WarnLevel
	ErrorLevel
)

type LogWithWriters

type LogWithWriters struct {
	sync.Mutex
	log.Logger
	// contains filtered or unexported fields
}

LogWithWriters is a logger used with the pack CLI, allowing users to print logs for various levels, including Info, Debug and Error

func NewLogWithWriters

func NewLogWithWriters(stdout, stderr io.Writer, opts ...func(*LogWithWriters)) *LogWithWriters

NewLogWithWriters creates a logger to be used with pack CLI.

func (*LogWithWriters) HandleLog

func (lw *LogWithWriters) HandleLog(e *log.Entry) error

HandleLog handles log events, printing entries appropriately

func (*LogWithWriters) IsVerbose

func (lw *LogWithWriters) IsVerbose() bool

IsVerbose returns whether verbose logging is on

func (*LogWithWriters) WantQuiet

func (lw *LogWithWriters) WantQuiet(f bool)

WantQuiet reduces the number of logs returned

func (*LogWithWriters) WantTime

func (lw *LogWithWriters) WantTime(f bool)

WantTime turns timestamps on in log entries

func (*LogWithWriters) WantVerbose

func (lw *LogWithWriters) WantVerbose(f bool)

WantVerbose increases the number of logs returned

func (*LogWithWriters) Writer

func (lw *LogWithWriters) Writer() io.Writer

Writer returns the base Writer for the LogWithWriters

func (*LogWithWriters) WriterForLevel

func (lw *LogWithWriters) WriterForLevel(level Level) io.Writer

WriterForLevel returns a Writer for the given Level

type Logger

type Logger interface {
	Debug(msg string)
	Debugf(fmt string, v ...interface{})

	Info(msg string)
	Infof(fmt string, v ...interface{})

	Warn(msg string)
	Warnf(fmt string, v ...interface{})

	Error(msg string)
	Errorf(fmt string, v ...interface{})

	Writer() io.Writer

	IsVerbose() bool
}

Logger defines behavior required by a logging package used by pack libraries

func NewSimpleLogger

func NewSimpleLogger(w io.Writer) Logger

NewSimpleLogger creates a simple logger for the pack library.

type PrefixWriter

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

PrefixWriter is a buffering writer that prefixes each new line. Close should be called to properly flush the buffer.

func NewPrefixWriter

func NewPrefixWriter(w io.Writer, prefix string, opts ...PrefixWriterOption) *PrefixWriter

NewPrefixWriter writes by w will be prefixed

func (*PrefixWriter) Close

func (w *PrefixWriter) Close() error

Close writes any pending data in the buffer

func (*PrefixWriter) Write

func (w *PrefixWriter) Write(data []byte) (int, error)

Write writes bytes to the embedded log function

type PrefixWriterOption

type PrefixWriterOption func(c *PrefixWriter)

func WithReaderFactory

func WithReaderFactory(factory func(data []byte) io.Reader) PrefixWriterOption