pubsub

type MsgHandler func(context.Context, []byte)

type Pub interface {
	// Publish publishes data to the channel ch
	Publish(ctx context.Context, ch string, data []byte) error
}

type PubSub interface {
	Pub
	Sub

	// Start does the initialisation work to bootstrap a PubSub adapter.
	// For example, this function may open a connection, start an event loop, etc.
	Start(ctx context.Context) error
	// Drain signals to the pubsub client/server that inbound messages should
	// no longer be accepted, but outbound messages can still be delivered.
	Drain()
	// Close closes the client/server for both inbound/outbound messages
	Close() error
}

type Sub interface {
	// Subscribe subscribes the message handler h to the channel ch.
	// All subscriptions with the same q will form a queue group.
	// Each message will be delivered to only one subscriber per queue group.
	Subscribe(q, ch string, h MsgHandler) error
}