try refactoring && decomposition subsribe && update deps

event.go

@@ -48,3 +48,10 @@ var eventPool = sync.Pool{
 		return &event{msg: &broker.Message{}}
 	},
 }
+
+func (p *event) reset() {
+	clear(p.msg.Header)
+	p.msg.Body = p.msg.Body[:0]
+	p.err = nil
+	p.ack = false
+}