# Functions
NewBlockchainReactor creates a new reactor instance.
NopMetrics returns no-op Metrics.
PrometheusMetrics returns metrics for in and out events, errors, etc.
# Constants
BlockchainChannel is a channel for blocks and status updates (`BlockStore` height).
MetricsSubsystem is a subsystem shared by all metrics exposed by this package.
# Structs
BlockchainReactor handles fast sync protocol.
Metrics contains metrics exposed by this package.
Routine is a structure that models a finite state machine as serialized stream of events processed by a handle function.