tailfile

Documentation

Overview

Package tailfile provides helper functions to read the nth lines of any ReadSeeker.

Index

• Variables
• func NewTailReader(ctx context.Context, r SizeReaderAt, reqLines int) (*io.SectionReader, int, error)
• func NewTailReaderWithDelimiter(ctx context.Context, r SizeReaderAt, reqLines int, delimiter []byte) (*io.SectionReader, int, error)
• func TailFile(f *os.File, n int) ([][]byte, error)
• type SizeReaderAt

Variables

var ErrNonPositiveLinesNumber = errors.New("The number of lines to extract from the file must be positive")

ErrNonPositiveLinesNumber is an error returned if the lines number was negative.

Functions

func NewTailReader

func NewTailReader(ctx context.Context, r SizeReaderAt, reqLines int) (*io.SectionReader, int, error)

NewTailReader scopes the passed in reader to just the last N lines passed in

func NewTailReaderWithDelimiter

func NewTailReaderWithDelimiter(ctx context.Context, r SizeReaderAt, reqLines int, delimiter []byte) (*io.SectionReader, int, error)

NewTailReaderWithDelimiter scopes the passed in reader to just the last N lines passed in In this case a "line" is defined by the passed in delimiter.

Delimiter lengths should be generally small, no more than 12 bytes

func TailFile

func TailFile(f *os.File, n int) ([][]byte, error)

TailFile returns last n lines of the passed in file.

Types

type SizeReaderAt

type SizeReaderAt interface {
	io.ReaderAt
	Size() int64
}

SizeReaderAt is an interface used to get a ReaderAt as well as the size of the underlying reader. Note that the size of the underlying reader should not change when using this interface.