chainindexer

Documentation

Index

• type BloomIndexer
  • func (b *BloomIndexer) Commit() error
  • func (b *BloomIndexer) Process(header *block.Header)
  • func (b *BloomIndexer) Reset(section uint64, lastSectionHead types.Hash) error
• type ChainIndexer
  • func NewBloomIndexer(db database.IDatabase, size uint64) *ChainIndexer
  • func NewChainIndexer(chainDb, indexDb database.IDatabase, backend ChainIndexerBackend, ...) *ChainIndexer
  • func (c *ChainIndexer) AddChildIndexer(indexer *ChainIndexer)
  • func (c *ChainIndexer) AddKnownSectionHead(section uint64, shead types.Hash)
  • func (c *ChainIndexer) Close() error
  • func (c *ChainIndexer) SectionHead(section uint64) types.Hash
  • func (c *ChainIndexer) Sections() (uint64, uint64, types.Hash)
  • func (c *ChainIndexer) Start(chain ChainIndexerChain)
• type ChainIndexerBackend
• type ChainIndexerChain

Types

type BloomIndexer

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

BloomIndexer implements a core.ChainIndexer, building up a rotated bloom bits index for the bchain header bloom filters, permitting blazing fast filtering.

func (*BloomIndexer) Commit

func (b *BloomIndexer) Commit() error

Commit implements core.ChainIndexerBackend, finalizing the bloom section and writing it out into the database.

func (*BloomIndexer) Process

func (b *BloomIndexer) Process(header *block.Header)

Process implements core.ChainIndexerBackend, adding a new header's bloom into the index.

func (*BloomIndexer) Reset

func (b *BloomIndexer) Reset(section uint64, lastSectionHead types.Hash) error

Reset implements core.ChainIndexerBackend, starting a new bloombits index section.

type ChainIndexer

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

ChainIndexer does a post-processing job for equally sized sections of the canonical chain (like BlooomBits and CHT structures). A ChainIndexer is connected to the blockchain through the event system by starting a ChainEventLoop in a goroutine.

Further child ChainIndexers can be added which use the output of the parent section indexer. These child indexers receive new head notifications only after an entire section has been finished or in case of rollbacks that might affect already finished sections.

func NewBloomIndexer

func NewBloomIndexer(db database.IDatabase, size uint64) *ChainIndexer

NewBloomIndexer returns a chain indexer that generates bloom bits data for the canonical chain for fast logs filtering.

func NewChainIndexer

func NewChainIndexer(chainDb, indexDb database.IDatabase, backend ChainIndexerBackend, section, confirm uint64, throttling time.Duration, kind string) *ChainIndexer

NewChainIndexer creates a new chain indexer to do background processing on chain segments of a given size after certain number of confirmations passed. The throttling parameter might be used to prevent database thrashing.

func (*ChainIndexer) AddChildIndexer

func (c *ChainIndexer) AddChildIndexer(indexer *ChainIndexer)

AddChildIndexer adds a child ChainIndexer that can use the output of this one

func (*ChainIndexer) AddKnownSectionHead

func (c *ChainIndexer) AddKnownSectionHead(section uint64, shead types.Hash)

AddKnownSectionHead marks a new section head as known/processed if it is newer than the already known best section head

func (*ChainIndexer) Close

func (c *ChainIndexer) Close() error

Close tears down all goroutines belonging to the indexer and returns any error that might have occurred internally.

func (*ChainIndexer) SectionHead

func (c *ChainIndexer) SectionHead(section uint64) types.Hash

SectionHead retrieves the last block hash of a processed section from the index database.

func (*ChainIndexer) Sections

func (c *ChainIndexer) Sections() (uint64, uint64, types.Hash)

Sections returns the number of processed sections maintained by the indexer and also the information about the last header indexed for potential canonical verifications.

func (*ChainIndexer) Start

func (c *ChainIndexer) Start(chain ChainIndexerChain)

Start creates a goroutine to feed chain head events into the indexer for cascading background processing. Children do not need to be started, they are notified about new events by their parents.

type ChainIndexerBackend

type ChainIndexerBackend interface {
	// Reset initiates the processing of a new chain segment, potentially terminating
	// any partially completed operations (in case of a reorg).
	Reset(section uint64, prevHead types.Hash) error

	// Process crunches through the next header in the chain segment. The caller
	// will ensure a sequential order of headers.
	Process(header *block.Header)

	// Commit finalizes the section metadata and stores it into the database.
	Commit() error
}

ChainIndexerBackend defines the methods needed to process chain segments in the background and write the segment results into the database. These can be used to create filter blooms or CHTs.

type ChainIndexerChain

type ChainIndexerChain interface {
	// CurrentHeader retrieves the latest locally known header.
	CurrentHeader() *block.Header

	// SubscribeChainEvent subscribes to new head header notifications.
	SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription
}

ChainIndexerChain interface is used for connecting the indexer to a blockchain