cluster

type CServer struct {
	CSPid        int
	CSPeers      []int
	ChannelIn    chan *Envelope
	ChannelOut   chan *Envelope
	ChannelClose chan bool
	Address      string
}

type Envelope struct {
	// On the sender side, Pid identifies the receiving peer. If instead, Pid is
	// set to cluster.BROADCAST, the message is sent to all peers. On the receiver side, the
	// Id is always set to the original sender. If the Id is not found, the message is silently dropped
	Pid int

	// An id that globally and uniquely identifies the message, meant for duplicate detection at
	// higher levels. It is opaque to this package.
	MsgId int64

	// the actual message.
	Msg interface{}
}

type PidServer struct {
	Pid    int
	Server *CServer
}

type Server interface {
	// Id of this server
	Pid() int

	// array of other servers' ids in the same cluster
	Peers() []int

	// the channel to use to send messages to other peers
	// Note that there are no guarantees of message delivery, and messages
	// are silently dropped
	Outbox() chan *Envelope

	// the channel to receive messages from other peers.
	Inbox() chan *Envelope
}