pullsync

Documentation

Overview

Package pullsync contains protocol that is used to ensure that there is correct chunk replication in the neighborhood of the node.

The protocol is used to exchange information about what chunks are stored on other nodes and if necessary pull any chunks it needs. It also takes care that chunks are not synced twice.

The pullsync protocol uses Protobuf messages for encoding. It then exposes several functions which use those messages to start the exchange of other node cursors using `GetCursors` function, after which node can schedule syncing of chunks using `SyncInterval` function, and in the case of any errors or timed-out operations cancel syncing using `CancelRuid`.

Package pullsync provides the pullsync protocol implementation.

Index

• Constants
• Variables
• type Interface
• type Syncer
  • func New(streamer p2p.Streamer, storage pullstorage.Storer, unwrap func(swarm.Chunk), ...) *Syncer
  • func (s *Syncer) CancelRuid(ctx context.Context, peer swarm.Address, ruid uint32) (err error)
  • func (s *Syncer) Close() error
  • func (s *Syncer) GetCursors(ctx context.Context, peer swarm.Address) (retr []uint64, err error)
  • func (s *Syncer) Metrics() []prometheus.Collector
  • func (s *Syncer) Protocol() p2p.ProtocolSpec
  • func (s *Syncer) Rate() float64
  • func (s *Syncer) SyncInterval(ctx context.Context, peer swarm.Address, bin uint8, from, to uint64) (topmost uint64, ruid uint32, err error)

Constants

const MaxCursor = math.MaxUint64

Variables

var (
	ErrUnsolicitedChunk = errors.New("peer sent unsolicited chunk")
)

Types

type Interface

type Interface interface {
	// SyncInterval syncs a requested interval from the given peer.
	// It returns the BinID of highest chunk that was synced from the given
	// interval. If the requested interval is too large, the downstream peer
	// has the liberty to provide less chunks than requested.
	SyncInterval(ctx context.Context, peer swarm.Address, bin uint8, from, to uint64) (topmost uint64, ruid uint32, err error)
	// GetCursors retrieves all cursors from a downstream peer.
	GetCursors(ctx context.Context, peer swarm.Address) ([]uint64, error)
	// CancelRuid cancels active pullsync operation identified by ruid on
	// a downstream peer.
	CancelRuid(ctx context.Context, peer swarm.Address, ruid uint32) error
}

Interface is the PullSync interface.

type Syncer

type Syncer struct {
	Interface
	io.Closer
	// contains filtered or unexported fields
}

func New

func New(streamer p2p.Streamer, storage pullstorage.Storer, unwrap func(swarm.Chunk), validStamp postage.ValidStampFn, logger log.Logger) *Syncer

func (*Syncer) CancelRuid

func (s *Syncer) CancelRuid(ctx context.Context, peer swarm.Address, ruid uint32) (err error)

func (*Syncer) Close

func (s *Syncer) Close() error

func (*Syncer) GetCursors

func (s *Syncer) GetCursors(ctx context.Context, peer swarm.Address) (retr []uint64, err error)

func (*Syncer) Metrics

func (s *Syncer) Metrics() []prometheus.Collector

func (*Syncer) Protocol

func (s *Syncer) Protocol() p2p.ProtocolSpec

func (*Syncer) Rate

func (s *Syncer) Rate() float64

func (*Syncer) SyncInterval

func (s *Syncer) SyncInterval(ctx context.Context, peer swarm.Address, bin uint8, from, to uint64) (topmost uint64, ruid uint32, err error)

SyncInterval syncs a requested interval from the given peer. It returns the BinID of highest chunk that was synced from the given interval. If the requested interval is too large, the downstream peer has the liberty to provide less chunks than requested.