# Functions
NewHeartbeatHandler instantiates a HeartbeatHandler instance.
NewInMemTestServer creates a test server in memory.
NewServer creates a new server TODO clean up config, make root config contains network, dispatch and chainservice.
StartServer starts a node server.
# Structs
HeartbeatHandler is the handler to periodically log the system key metrics.
Server is the iotex server instance containing all components.