forward

Documentation

Overview

Package forward is used for creating a data forwarder for the map UDF vertex.

Package forward does the Read (fromBufferPartition) -> Process (map UDF) -> Forward (toBuffers) -> Ack (fromBufferPartition) loop.

Index

• func DefaultOptions() *options
• type GoWhere
  • func (gw GoWhere) WhereTo(ks []string, ts []string) ([]VertexBuffer, error)
• type InterStepDataForward
  • func NewInterStepDataForward(vertexInstance *dfv1.VertexInstance, fromStep isb.BufferReader, ...) (*InterStepDataForward, error)
  • func (isdf *InterStepDataForward) ForceStop()
  • func (isdf *InterStepDataForward) IsShuttingDown() (bool, error)
  • func (isdf *InterStepDataForward) Start() <-chan struct{}
  • func (isdf *InterStepDataForward) Stop()
• type Option
  • func WithLogger(l *zap.SugaredLogger) Option
  • func WithReadBatchSize(f int64) Option
  • func WithRetryInterval(f time.Duration) Option
  • func WithUDFConcurrency(f int) Option
  • func WithUDFStreaming(f bool) Option
• type Shutdown
  • func (s *Shutdown) String() string
• type StarterStopper
• type ToWhichStepDecider
• type VertexBuffer

Functions

func DefaultOptions

func DefaultOptions() *options

Types

type GoWhere

type GoWhere func([]string, []string) ([]VertexBuffer, error)

GoWhere is the step decider on where it needs to go

func (GoWhere) WhereTo

func (gw GoWhere) WhereTo(ks []string, ts []string) ([]VertexBuffer, error)

WhereTo decides where the data goes to.

type InterStepDataForward

type InterStepDataForward struct {
	FSD ToWhichStepDecider

	Shutdown
	// contains filtered or unexported fields
}

InterStepDataForward forwards the data from previous step to the current step via inter-step buffer.

func NewInterStepDataForward

func NewInterStepDataForward(
	vertexInstance *dfv1.VertexInstance,
	fromStep isb.BufferReader,
	toSteps map[string][]isb.BufferWriter,
	fsd ToWhichStepDecider,
	applyUDF applier.MapApplier,
	applyUDFStream applier.MapStreamApplier,
	fetchWatermark fetch.Fetcher,
	publishWatermark map[string]publish.Publisher,
	idleManager wmb.IdleManager,
	opts ...Option) (*InterStepDataForward, error)

NewInterStepDataForward creates an inter-step forwarder.

func (*InterStepDataForward) ForceStop

func (isdf *InterStepDataForward) ForceStop()

ForceStop sets up the force shutdown flag.

func (*InterStepDataForward) IsShuttingDown

func (isdf *InterStepDataForward) IsShuttingDown() (bool, error)

IsShuttingDown returns whether we can stop processing.

func (*InterStepDataForward) Start

func (isdf *InterStepDataForward) Start() <-chan struct{}

Start starts reading the buffer and forwards to the next buffers. Call `Stop` to stop.

func (*InterStepDataForward) Stop

func (isdf *InterStepDataForward) Stop()

Stop stops the processing.

type Option

type Option func(*options) error

func WithLogger

func WithLogger(l *zap.SugaredLogger) Option

WithLogger is used to return logger information

func WithReadBatchSize

func WithReadBatchSize(f int64) Option

WithReadBatchSize sets the read batch size

func WithRetryInterval

func WithRetryInterval(f time.Duration) Option

WithRetryInterval sets the retry interval

func WithUDFConcurrency

func WithUDFConcurrency(f int) Option

WithUDFConcurrency sets concurrency for map UDF processing

func WithUDFStreaming

func WithUDFStreaming(f bool) Option

WithUDFStreaming sets streaming for map UDF processing

type Shutdown

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

Shutdown tracks and enforces the shutdown activity.

func (*Shutdown) String

func (s *Shutdown) String() string

type StarterStopper

type StarterStopper interface {
	Start() <-chan struct{}
	Stop()
	ForceStop()
}

StarterStopper starts/stops the forwarding.

type ToWhichStepDecider

type ToWhichStepDecider interface {
	// WhereTo decides where to forward the result to based on the name of the step it returns.
	// It supports 2 addition keywords which need not be a step name. They are "ALL" and "DROP"
	// where former means, forward to all the neighbouring steps and latter means do not forward anywhere.
	WhereTo([]string, []string) ([]VertexBuffer, error)
}

ToWhichStepDecider decides which step to forward after applying the WhereTo function.

type VertexBuffer

type VertexBuffer struct {
	ToVertexName         string
	ToVertexPartitionIdx int32
}

VertexBuffer points to the partition of a buffer owned by the vertex.