listener

Documentation

Overview

Package listener is the listener used to pull in chain events

Index

• Variables
• type ContractListener
  • func NewChainListener(omnirpcClient client.EVM, store listenerDB.ChainListenerDB, ...) (ContractListener, error)
• type HandleLog
• type NewBlockHandler
• type Option
  • func WithNewBlockHandler(handler NewBlockHandler) Option
  • func WithPollInterval(interval time.Duration) Option

Variables

var (

	// ErrNoLatestBlockForChainID is returned when no block exists for the chain.
	ErrNoLatestBlockForChainID = listenerDB.ErrNoLatestBlockForChainID
)

Types

type ContractListener

type ContractListener interface {
	// Listen starts the listener and call HandleLog for each event
	Listen(ctx context.Context, handler HandleLog) error
	// LatestBlock gets the last recorded latest block from the rpc.
	// this is NOT last indexed. It is provided as a helper for checking confirmation count
	LatestBlock() uint64
	// Address gets the address of the contract this listener is listening to
	Address() common.Address
}

ContractListener listens for chain events and calls HandleLog.

func NewChainListener

func NewChainListener(omnirpcClient client.EVM, store listenerDB.ChainListenerDB, address common.Address, initialBlock uint64, handler metrics.Handler, options ...Option) (ContractListener, error)

NewChainListener creates a new chain listener.

type HandleLog

type HandleLog func(ctx context.Context, log types.Log) error

HandleLog is the handler for a log event in the event this errors, the range will be reparsed.

type NewBlockHandler

type NewBlockHandler func(ctx context.Context, block uint64) error

NewBlockHandler is a function that is called when a new block is detected.

type Option

type Option func(*chainListener)

Option is a functional option for chainListener.

func WithNewBlockHandler

func WithNewBlockHandler(handler NewBlockHandler) Option

WithNewBlockHandler sets the new block handler.

func WithPollInterval

func WithPollInterval(interval time.Duration) Option

WithPollInterval sets the poll interval.