update broker to match go-micro broker, TODO: finish rabbitmq queue fanout

nats.go

@@ -15,13 +15,35 @@ type nbroker struct {
 }
 
 type subscriber struct {
-	s *nats.Subscription
+	s    *nats.Subscription
+	opts broker.SubscribeOptions
+}
+
+type publication struct {
+	t string
+	m *broker.Message
 }
 
 func init() {
 	cmd.Brokers["nats"] = NewBroker
 }
 
+func (n *publication) Topic() string {
+	return n.t
+}
+
+func (n *publication) Message() *broker.Message {
+	return n.m
+}
+
+func (n *publication) Ack() error {
+	return nil
+}
+
+func (n *subscriber) Config() broker.SubscribeOptions {
+	return n.opts
+}
+
 func (n *subscriber) Topic() string {
 	return n.s.Subject
 }
@@ -57,11 +79,11 @@ func (n *nbroker) Disconnect() error {
 	return nil
 }
 
-func (n *nbroker) Init() error {
+func (n *nbroker) Init(opts ...broker.Option) error {
 	return nil
 }
 
-func (n *nbroker) Publish(topic string, msg *broker.Message) error {
+func (n *nbroker) Publish(topic string, msg *broker.Message, opts ...broker.PublishOption) error {
 	b, err := json.Marshal(msg)
 	if err != nil {
 		return err
@@ -69,18 +91,35 @@ func (n *nbroker) Publish(topic string, msg *broker.Message) error {
 	return n.conn.Publish(topic, b)
 }
 
-func (n *nbroker) Subscribe(topic string, handler broker.Handler) (broker.Subscriber, error) {
-	sub, err := n.conn.Subscribe(topic, func(msg *nats.Msg) {
+func (n *nbroker) Subscribe(topic string, handler broker.Handler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
+	opt := broker.SubscribeOptions{
+		AutoAck: true,
+	}
+
+	for _, o := range opts {
+		o(&opt)
+	}
+
+	fn := func(msg *nats.Msg) {
 		var m *broker.Message
 		if err := json.Unmarshal(msg.Data, &m); err != nil {
 			return
 		}
-		handler(m)
-	})
+		handler(&publication{m: m, t: topic})
+	}
+
+	var sub *nats.Subscription
+	var err error
+
+	if len(opt.Queue) > 0 {
+		sub, err = n.conn.QueueSubscribe(topic, opt.Queue, fn)
+	} else {
+		sub, err = n.conn.Subscribe(topic, fn)
+	}
 	if err != nil {
 		return nil, err
 	}
-	return &subscriber{s: sub}, nil
+	return &subscriber{s: sub, opts: opt}, nil
 }
 
 func (n *nbroker) String() string {