ledger

type Factory interface {
	// GetOrCreate gets an existing ledger (if it exists)
	// or creates it if it does not
	GetOrCreate(chainID string) (ReadWriter, error)

	// ChainIDs returns the chain IDs the Factory is aware of
	ChainIDs() []string

	// Close releases all resources acquired by the factory
	Close()
}

type Iterator interface {
	// Next blocks until there is a new block available, or returns an error if
	// the next block is no longer retrievable
	Next() (*cb.Block, cb.Status)
	// ReadyChan supplies a channel which will block until Next will not block
	ReadyChan() <-chan struct{}
}

type NotFoundErrorIterator struct{}

type ReadWriter interface {
	Reader
	Writer
}

type Reader interface {
	// Iterator returns an Iterator, as specified by a cb.SeekInfo message, and
	// its starting block number
	Iterator(startType *ab.SeekPosition) (Iterator, uint64)
	// Height returns the number of blocks on the ledger
	Height() uint64
}

type Writer interface {
	// Append a new block to the ledger
	Append(block *cb.Block) error
}