server

type Authenticator interface {
	// Authenticate based on the given login and passcode, either of which might be nil.
	// Returns true if authentication is successful, false otherwise.
	Authenticate(login, passcode string) bool
}

type QueueStorage interface {
	// Enqueue adds a MESSAGE frame to the end of the queue.
	Enqueue(queue string, frame *frame.Frame) error

	// Requeue adds a MESSAGE frame to the head of the queue.
	// This will happen if a client fails to acknowledge receipt.
	Requeue(queue string, frame *frame.Frame) error

	// Dequeue removes a frame from the head of the queue.
	// Returns nil if no frame is available.
	Dequeue(queue string) (*frame.Frame, error)

	// Start is called at server startup. Allows the queue storage
	// to perform any initialization.
	Start()

	// Stop is called prior to server shutdown. Allows the queue storage
	// to perform any cleanup, such as flushing to disk.
	Stop()
}

type Server struct {
	Addr          string        // TCP address to listen on, DefaultAddr if empty
	Authenticator Authenticator // Authenticates login/passcodes. If nil no authentication is performed
	QueueStorage  QueueStorage  // Implementation of queue storage. If nil, in-memory queues are used.
	HeartBeat     time.Duration // Preferred value for heart-beat read/write timeout, if zero, then DefaultHeartBeat.
}