sync

Documentation

Index

• type Option
  • func WithBlockTime(duration time.Duration) Option
  • func WithMetrics() Option
  • func WithParams(new Parameters) Option
  • func WithRecencyThreshold(threshold time.Duration) Option
  • func WithTrustingPeriod(duration time.Duration) Option
• type Parameters
  • func DefaultParameters() Parameters
  • func (p *Parameters) Validate() error
• type State
  • func (s State) Duration() time.Duration
  • func (s State) Finished() bool
• type Syncer
  • func NewSyncer[H header.Header[H]](getter header.Getter[H], store header.Store[H], sub header.Subscriber[H], ...) (*Syncer[H], error)
  • func (s *Syncer[H]) Head(ctx context.Context, _ ...header.HeadOption[H]) (H, error)
  • func (s *Syncer[H]) Start(ctx context.Context) error
  • func (s *Syncer[H]) State() State
  • func (s *Syncer[H]) Stop(context.Context) error
  • func (s *Syncer[H]) SyncWait(ctx context.Context) error

Types

type Option

type Option func(*Parameters)

Option is the functional option that is applied to the Syner instance to configure its parameters.

func WithBlockTime

func WithBlockTime(duration time.Duration) Option

WithBlockTime is a functional option that configures the `blockTime` parameter.

func WithMetrics

func WithMetrics() Option

WithMetrics enables Metrics on Syncer.

func WithParams

func WithParams(new Parameters) Option

WithParams is a functional option that overrides Parameters.

func WithRecencyThreshold

func WithRecencyThreshold(threshold time.Duration) Option

WithRecencyThreshold is a functional option that configures the `recencyThreshold` parameter.

func WithTrustingPeriod

func WithTrustingPeriod(duration time.Duration) Option

WithTrustingPeriod is a functional option that configures the `TrustingPeriod` parameter.

type Parameters

type Parameters struct {
	// TrustingPeriod is period through which we can trust a header's validators set.
	//
	// Should be significantly less than the unbonding period (e.g. unbonding
	// period = 3 weeks, trusting period = 2 weeks).
	//
	// More specifically, trusting period + time needed to check headers + time
	// needed to report and punish misbehavior should be less than the unbonding
	// period.
	TrustingPeriod time.Duration
	// contains filtered or unexported fields
}

Parameters is the set of parameters that must be configured for the syncer.

func DefaultParameters

func DefaultParameters() Parameters

DefaultParameters returns the default params to configure the syncer.

func (*Parameters) Validate

func (p *Parameters) Validate() error

type State

type State struct {
	ID         uint64      `json:"id"`          // incrementing ID of a sync
	Height     uint64      `json:"height"`      // height at the moment when State is requested for a sync
	FromHeight uint64      `json:"from_height"` // the starting point of a sync
	ToHeight   uint64      `json:"to_height"`   // the ending point of a sync
	FromHash   header.Hash `json:"from_hash"`
	ToHash     header.Hash `json:"to_hash"`
	Start      time.Time   `json:"start"`
	End        time.Time   `json:"end"`
	Error      string      `json:"error,omitempty"` // the error that might happen within a sync
}

State collects all the information about a sync.

func (State) Duration

func (s State) Duration() time.Duration

Duration returns the duration of the sync.

func (State) Finished

func (s State) Finished() bool

Finished returns true if sync is done, false otherwise.

type Syncer

type Syncer[H header.Header[H]] struct {
	Params *Parameters
	// contains filtered or unexported fields
}

Syncer implements efficient synchronization for headers.

Subjective Head - the latest known local valid header and a sync target. Network Head - the latest valid network-wide header. Becomes subjective once applied locally.

There are two main processes running in Syncer: - Main syncing loop(s.syncLoop)

• Performs syncing from the latest stored header up to the latest known Subjective Head
• Syncs by requesting missing headers from Exchange or
• By accessing cache of pending headers

- Receives every new Network Head from PubSub gossip subnetwork (s.incomingNetworkHead)

• Validates against the latest known Subjective Head, is so
• Sets as the new Subjective Head, which
• if there is a gap between the previous and the new Subjective Head
• Triggers s.syncLoop and saves the Subjective Head in the pending so s.syncLoop can access it

func NewSyncer

func NewSyncer[H header.Header[H]](
	getter header.Getter[H],
	store header.Store[H],
	sub header.Subscriber[H],
	opts ...Option,
) (*Syncer[H], error)

NewSyncer creates a new instance of Syncer.

func (*Syncer[H]) Head

func (s *Syncer[H]) Head(ctx context.Context, _ ...header.HeadOption[H]) (H, error)

Head returns the Network Head.

Known subjective head is considered network head if it is recent enough(now-timestamp<=blocktime) Otherwise, we attempt to request recent network head from a trusted peer and set as the new subjective head, assuming that trusted peer is always fully synced.

The request is limited with 2 seconds and otherwise potentially unrecent header is returned.

func (*Syncer[H]) Start

func (s *Syncer[H]) Start(ctx context.Context) error

Start starts the syncing routine.

func (*Syncer[H]) State

func (s *Syncer[H]) State() State

State reports state of the current (if in progress), or last sync (if finished). Note that throughout the whole Syncer lifetime there might an initial sync and multiple catch-ups. All of them are treated as different syncs with different state IDs and other information.

func (*Syncer[H]) Stop

func (s *Syncer[H]) Stop(context.Context) error

Stop stops Syncer.

func (*Syncer[H]) SyncWait

func (s *Syncer[H]) SyncWait(ctx context.Context) error

SyncWait blocks until ongoing sync is done.