Improve bus (#3)

* Improve bus
* Add ticket log

bus/request.go

@@ -0,0 +1,36 @@
+package bus
+
+import (
+	"encoding/json"
+	"log"
+
+	"github.com/arangodb/go-driver"
+	emitter "github.com/emitter-io/go/v2"
+)
+
+const ChannelRequest = "request"
+
+type RequestMsg struct {
+	IDs      []driver.DocumentID `json:"ids"`
+	Function string              `json:"function"`
+	User     string              `json:"user"`
+}
+
+func (b *Bus) PublishRequest(user, f string, ids []driver.DocumentID) error {
+	return b.jsonPublish(&RequestMsg{
+		User:     user,
+		Function: f,
+		IDs:      ids,
+	}, ChannelRequest, b.config.requestKey)
+}
+
+func (b *Bus) SubscribeRequest(f func(msg *RequestMsg)) error {
+	return b.safeSubscribe(b.config.requestKey, ChannelRequest, func(c *emitter.Client, m emitter.Message) {
+		var msg RequestMsg
+		if err := json.Unmarshal(m.Payload(), &msg); err != nil {
+			log.Println(err)
+			return
+		}
+		go f(&msg)
+	})
+}