mapper

Documentation

Index

• Variables
• func WithTransition(status Status, transition TransitionFunc) func(*FSM)
• type Config
• type FSM
  • func NewFSM(state *State, options ...func(*FSM)) *FSM
  • func (f *FSM) Run() error
  • func (f *FSM) Stop() error
• type Feeder
• type Forest
• type Loader
• type Option
  • func WithBootstrapState(bootstrap bool) Option
  • func WithSkipRegisters(skip bool) Option
  • func WithWaitInterval(interval time.Duration) Option
• type State
  • func EmptyState(forest Forest) *State
• type Status
  • func (s Status) String() string
• type TransitionFunc
• type Transitions
  • func NewTransitions(log zerolog.Logger, load Loader, chain dps.Chain, feed Feeder, read dps.Reader, ...) *Transitions
  • func (t *Transitions) BootstrapState(s *State) error
  • func (t *Transitions) CollectRegisters(s *State) error
  • func (t *Transitions) ForwardHeight(s *State) error
  • func (t *Transitions) IndexChain(s *State) error
  • func (t *Transitions) InitializeMapper(s *State) error
  • func (t *Transitions) MapRegisters(s *State) error
  • func (t *Transitions) ResumeIndexing(s *State) error
  • func (t *Transitions) UpdateTree(s *State) error

Variables

var DefaultConfig = Config{
	BootstrapState: false,
	SkipRegisters:  false,
	WaitInterval:   100 * time.Millisecond,
}

DefaultConfig is the default configuration for the Mapper.

Functions

func WithTransition

func WithTransition(status Status, transition TransitionFunc) func(*FSM)

WithTransition specifies which TransitionFunc should be used when the state machine has the given status.

Types

type Config

type Config struct {
	BootstrapState bool
	SkipRegisters  bool
	WaitInterval   time.Duration
}

Config contains optional parameters for the Mapper.

type FSM

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

FSM is a finite state machine which is used to map block data from multiple sources into the DPS index.

func NewFSM

func NewFSM(state *State, options ...func(*FSM)) *FSM

NewFSM returns a new FSM using the given state and options.

func (*FSM) Run

func (f *FSM) Run() error

Run starts the state machine.

func (*FSM) Stop

func (f *FSM) Stop() error

Stop gracefully stops the state machine.

type Feeder

type Feeder interface {
	Update() (*ledger.TrieUpdate, error)
}

Feeder represents something that can be consumed to get trie updates in chronological order.

type Forest

type Forest interface {
	Save(tree *trie.MTrie, paths []ledger.Path, parent flow.StateCommitment)
	Has(commit flow.StateCommitment) bool
	Tree(commit flow.StateCommitment) (*trie.MTrie, bool)
	Paths(commit flow.StateCommitment) ([]ledger.Path, bool)
	Parent(commit flow.StateCommitment) (flow.StateCommitment, bool)
	Reset(finalized flow.StateCommitment)
}

Forest represents a multitude of trees which are mapped by their state commitment hash.

type Loader

type Loader interface {
	Trie() (*trie.MTrie, error)
}

Loader represents something that loads its checkpoint and builds it into a trie.

type Option

type Option func(*Config)

Option is an option that can be given to the mapper to configure optional parameters on initialization.

func WithBootstrapState

func WithBootstrapState(bootstrap bool) Option

WithBootstrapState makes the mapper bootstrap the state from a root checkpoint. If not set, it will resume indexing from a previous trie.

func WithSkipRegisters

func WithSkipRegisters(skip bool) Option

WithSkipRegisters makes the mapper skip indexing of all ledger registers, which speeds up the run significantly and can be used for debugging purposes.

func WithWaitInterval

func WithWaitInterval(interval time.Duration) Option

WithWaitInterval sets the wait interval that we will wait before retrying to retrieve a trie update when it wasn't available.

type State

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

State is the state machine's state.

func EmptyState

func EmptyState(forest Forest) *State

EmptyState returns a new empty state that uses the given forest.

type Status

type Status uint8

Status is a representation of the state machine's status.

const (
	StatusInitialize Status = iota + 1
	StatusBootstrap
	StatusResume
	StatusIndex
	StatusUpdate
	StatusCollect
	StatusMap
	StatusForward
)

The following is an enumeration of all possible statuses the state machine can have.

func (Status) String

func (s Status) String() string

String implements the Stringer interface.

type TransitionFunc

type TransitionFunc func(*State) error

TransitionFunc is a function that is applied onto the state machine's state.

type Transitions

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

Transitions is what applies transitions to the state of an FSM.

func NewTransitions

func NewTransitions(log zerolog.Logger, load Loader, chain dps.Chain, feed Feeder, read dps.Reader, write dps.Writer, options ...Option) *Transitions

NewTransitions returns a Transitions component using the given dependencies and using the given options

func (*Transitions) BootstrapState

func (t *Transitions) BootstrapState(s *State) error

BootstrapState bootstraps the state by loading the checkpoint if there is one and initializing the elements subsequently used by the FSM.

func (*Transitions) CollectRegisters

func (t *Transitions) CollectRegisters(s *State) error

CollectRegisters reads the payloads for the next block to be indexed from the state's forest, unless payload indexing is disabled.

func (*Transitions) ForwardHeight

func (t *Transitions) ForwardHeight(s *State) error

ForwardHeight increments the height at which the mapping operates, and updates the last indexed height.

func (*Transitions) IndexChain

func (t *Transitions) IndexChain(s *State) error

IndexChain indexes chain data for the current height.

func (*Transitions) InitializeMapper

func (t *Transitions) InitializeMapper(s *State) error

InitializeMapper initializes the mapper by either going into bootstrapping or into resuming, depending on the configuration.

func (*Transitions) MapRegisters

func (t *Transitions) MapRegisters(s *State) error

MapRegisters maps the collected registers to the current block.

func (*Transitions) ResumeIndexing

func (t *Transitions) ResumeIndexing(s *State) error

ResumeIndexing resumes indexing the data from a previous run.

func (*Transitions) UpdateTree

func (t *Transitions) UpdateTree(s *State) error

UpdateTree updates the state's tree. If the state's forest already matches with the next block's state commitment, it immediately returns and sets the state's status to StatusMatched.