revert some changes

broker/broker.go

@@ -44,3 +44,27 @@ var (
 func NewBroker(opts ...Option) Broker {
 	return newHttpBroker(opts...)
 }
+
+func Init(opts ...Option) error {
+	return DefaultBroker.Init(opts...)
+}
+
+func Connect() error {
+	return DefaultBroker.Connect()
+}
+
+func Disconnect() error {
+	return DefaultBroker.Disconnect()
+}
+
+func Publish(topic string, msg *Message, opts ...PublishOption) error {
+	return DefaultBroker.Publish(topic, msg, opts...)
+}
+
+func Subscribe(topic string, handler Handler, opts ...SubscribeOption) (Subscriber, error) {
+	return DefaultBroker.Subscribe(topic, handler, opts...)
+}
+
+func String() string {
+	return DefaultBroker.String()
+}