logrotation

Documentation

Overview

Package logrotation provides a writer that automatically rotates logfiles if the set maximum size is reached or exceeded. Compression is enabled by default, but can be disabled if required.

Index

• Constants
• type CompressorFunc
• type Rotor
  • func NewRotor(path string, opts ...uint8) *Rotor
  • func (r *Rotor) Close() error
  • func (r *Rotor) Open() error
  • func (r *Rotor) Rotate() (err error)
  • func (r *Rotor) SetCompressor(cf CompressorFunc, ext string)
  • func (r *Rotor) Write(bts []byte) (n int, err error)

Constants

const (
	// OptionReportErrors enables the error reporting channel that informs
	// about errors that happen in the background and are otherwise ignored
	OptionReportErrors = iota
	// OptionNoCompression disabled the compression of Archived logs.
	OptionNoCompression
	// OptionGZip enables compression using gzip
	OptionGZip
	// OptionZlib enables compression using zip
	OptionZlib
	// OptionNoSync disables the synchronous flag when opening logfiles this
	// can yield double speed but may lead to data loss if the system is
	// turned off before a flush to disk happened
	OptionNoSync
	// OptionMaxCompression sets the compression level to maximum, thereby
	// taking longer but achieving better compression
	OptionMaxCompression
	// OptionMinCompression sets the compression level to minimum, thereby
	// speeding up compression drastically while also increasing the rotated
	// filesize substantially
	OptionMinCompression
)

Types

type CompressorFunc

type CompressorFunc func(io.Writer, io.Reader) error

CompressorFunc specifies the layout required to set custom compressors for the logfiles.

type Rotor

type Rotor struct {

	// Permissions indicate unix file permissions to apply. By default it's
	// 0o600
	Permissions os.FileMode

	// MaxFileSize is after what time the file is truncated. Default: 4 MiB
	MaxFileSize uint64
	// Retention is how many "old" logs are kept. Default: 2. This means you
	// have 3 files in total: file.log, file.log.1.gz, file.log.2.gz
	Retention int
	// KeptPercent is how many % (of lines) are kept when using flowing-mode
	// This value is only used if retention is 0 or below. The last x% of
	// lines are kept and mark the starting point of the new log. Default: 5
	//
	// Please note that this is an approximation. The percent-position will
	// sought and everything _after_ the next '\n' will be kept for the
	// rotated file.
	KeptPercent int

	// Errors is an unbuffered channel to get notified of errors while
	// rotating. It is only enabled when the Rotor was created with
	// OptionReportErrors
	Errors chan error
	// contains filtered or unexported fields
}

Rotor is the struct containing all Settings, file handlers, and functions required for logrotation.

func NewRotor

func NewRotor(path string, opts ...uint8) *Rotor

NewRotor generates a new Rotor with the given options overwriting the defaults. The defaults are: Permissions: 600, MaxFileSize: 4 MiB, Retention: 2, KeptPercent: 5, Compression: gzip (Default Compression)

func (*Rotor) Close

func (r *Rotor) Close() error

Close closes the underlying filedescriptor

func (*Rotor) Open

func (r *Rotor) Open() error

Open opens (or creates) the logfile specified when setting up the Rotor. Closing this file is the responsibility of the user.

func (*Rotor) Rotate

func (r *Rotor) Rotate() (err error)

Rotate triggers a rotation, independent of whether the limit size is reached or not.

func (*Rotor) SetCompressor

func (r *Rotor) SetCompressor(cf CompressorFunc, ext string)

SetCompressor allows setting a custom compression method for use when rotating

func (*Rotor) Write

func (r *Rotor) Write(bts []byte) (n int, err error)