BlocksDeliverer defines interface which actually helps to abstract the AtomicBroadcast_DeliverClient with only required method for blocks provider. This also decouples the production implementation of the gRPC stream from the code in order for the code to be more modular and testable.
type BlocksDeliverer interface {
// Recv retrieves a response from the ordering service
Recv() (*orderer.DeliverResponse, error)
// Send sends an envelope to the ordering service
Send(*common.Envelope) error
}
BlocksProvider used to read blocks from the ordering service for specified chain it subscribed to
type BlocksProvider interface {
// DeliverBlocks starts delivering and disseminating blocks
DeliverBlocks()
// Stop shutdowns blocks provider and stops delivering new blocks
Stop()
}
func NewBlocksProvider(chainID string, client StreamClient, gossip GossipServiceAdapter, mcs api.MessageCryptoService) BlocksProvider
NewBlocksProvider constructor function to create blocks deliverer instance
GossipServiceAdapter serves to provide basic functionality required from gossip service by delivery service
type GossipServiceAdapter interface {
// PeersOfChannel returns slice with members of specified channel
PeersOfChannel(gossipcommon.ChainID) []discovery.NetworkMember
// AddPayload adds payload to the local state sync buffer
AddPayload(chainID string, payload *gossip_proto.Payload) error
// Gossip the message across the peers
Gossip(msg *gossip_proto.GossipMessage)
}
LedgerInfo an adapter to provide the interface to query the ledger committer for current ledger height
type LedgerInfo interface {
// LedgerHeight returns current local ledger height
LedgerHeight() (uint64, error)
}
type StreamClient interface {
BlocksDeliverer
// Close closes the stream and its underlying connection
Close()
// Disconnect disconnects from the remote node.
Disconnect()
// Update the client on the last valid block number
UpdateReceived(blockNumber uint64)
}