shadowsocks_pbf

README

shadowsocks-pbf

Persistent bloom filter for shadowsocks.

It is mainly with reference to the mechanism of AOF (Append Only File) of redis.

However, there is still the problem of occupying memory. Visit disk-bloom-filter for another solution.

Thanks

• This project was born after discussed with rprx.
• Bloom filter is from go-shadowsocks2 and go-bloom.

Documentation

Index

• Constants
• Variables
• type AppendFsync
• type PBF
  • func New(path string, fsync AppendFsync, lengthIV uint8, slot int, capacity int, ...) (*PBF, error)
  • func NewFromFile(path string, fsync AppendFsync) (*PBF, error)
  • func (p *PBF) Add(b []byte) (err error)
  • func (p *PBF) Close() error
  • func (p *PBF) Snapshot() (err error)
  • func (p *PBF) Test(b []byte) bool

Constants

const (
	DefaultSFCapacity = 1e6
	// FalsePositiveRate
	DefaultSFFPR  = 1e-6
	DefaultSFSlot = 10
)

Those suggest value are all set according to https://github.com/shadowsocks/shadowsocks-org/issues/44#issuecomment-281021054 Due to this package contains various internal implementation so const named with DefaultBR prefix

Variables

var (
	SnapshotIsPerformingError = errors.New("another snapshot is performing")
	DamagedSnapshotError      = errors.New("the snapshot is damaged")
)

Types

type AppendFsync

type AppendFsync int

const (
	AppendFsyncAlways AppendFsync = iota
	AppendFsyncEverySec
	AppendFsyncNo
)

type PBF

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

PBF is mainly with reference to the mechanism of AOF (Append Only File) of redis.

func New

func New(path string, fsync AppendFsync, lengthIV uint8, slot int, capacity int, falsePositiveRate float64) (*PBF, error)

func NewFromFile

func NewFromFile(path string, fsync AppendFsync) (*PBF, error)

NewFromFile will try recovering from file

func (*PBF) Add

func (p *PBF) Add(b []byte) (err error)

func (*PBF) Close

func (p *PBF) Close() error

func (*PBF) Snapshot

func (p *PBF) Snapshot() (err error)

Snapshot save current binary value to the file. It is like the AOF rewrite, but the result of rewrite is binary of bloomRing to save more storage and speed up the loading.

func (*PBF) Test

func (p *PBF) Test(b []byte) bool