diff --git a/bot/handler/callback.go b/bot/handler/callback.go
new file mode 100644
index 0000000..d2619fc
--- /dev/null
+++ b/bot/handler/callback.go
@@ -0,0 +1,53 @@
+package handler
+
+import (
+	"errors"
+	"log"
+	"net/http"
+
+	"github.com/claustra01/calendeye/linebot"
+	"github.com/claustra01/calendeye/webhook"
+)
+
+func Callback(w http.ResponseWriter, req *http.Request, bot *linebot.LineBot, channelSecret string) {
+	log.Println("/callback called...")
+
+	cb, err := webhook.ParseRequest(channelSecret, req)
+	if err != nil {
+		log.Printf("Cannot parse request: %+v\n", err)
+		if errors.Is(err, webhook.ErrInvalidSignature) {
+			w.WriteHeader(http.StatusBadRequest)
+		} else {
+			w.WriteHeader(http.StatusInternalServerError)
+		}
+		return
+	}
+
+	log.Println("Handling events...")
+	for _, event := range cb.Events {
+		log.Printf("/callback called%+v...\n", event)
+
+		switch e := event.(type) {
+		case webhook.MessageEvent:
+			switch message := e.Message.(type) {
+			case webhook.TextMessageContent:
+				if _, err = bot.ReplyMessage(
+					&linebot.ReplyMessageRequest{
+						ReplyToken: e.ReplyToken,
+						Messages: []linebot.MessageInterface{
+							linebot.NewTextMessage(message.Text),
+						},
+					},
+				); err != nil {
+					log.Print(err)
+				} else {
+					log.Println("Sent text reply.")
+				}
+			default:
+				log.Printf("Unsupported message content: %T\n", e.Message)
+			}
+		default:
+			log.Printf("Unsupported message: %T\n", event)
+		}
+	}
+}
diff --git a/bot/server.go b/bot/server.go
index 90f08c5..ecec89b 100644
--- a/bot/server.go
+++ b/bot/server.go
@@ -1,13 +1,12 @@
 package main
 
 import (
-	"errors"
 	"log"
 	"net/http"
 	"os"
 
+	"github.com/claustra01/calendeye/handler"
 	"github.com/claustra01/calendeye/linebot"
-	"github.com/claustra01/calendeye/webhook"
 	"github.com/joho/godotenv"
 )
 
@@ -32,46 +31,7 @@ func main() {
 
 	// Setup HTTP Server for receiving requests from LINE platform
 	http.HandleFunc("/callback", func(w http.ResponseWriter, req *http.Request) {
-		log.Println("/callback called...")
-
-		cb, err := webhook.ParseRequest(channelSecret, req)
-		if err != nil {
-			log.Printf("Cannot parse request: %+v\n", err)
-			if errors.Is(err, webhook.ErrInvalidSignature) {
-				w.WriteHeader(http.StatusBadRequest)
-			} else {
-				w.WriteHeader(http.StatusInternalServerError)
-			}
-			return
-		}
-
-		log.Println("Handling events...")
-		for _, event := range cb.Events {
-			log.Printf("/callback called%+v...\n", event)
-
-			switch e := event.(type) {
-			case webhook.MessageEvent:
-				switch message := e.Message.(type) {
-				case webhook.TextMessageContent:
-					if _, err = bot.ReplyMessage(
-						&linebot.ReplyMessageRequest{
-							ReplyToken: e.ReplyToken,
-							Messages: []linebot.MessageInterface{
-								linebot.NewTextMessage(message.Text),
-							},
-						},
-					); err != nil {
-						log.Print(err)
-					} else {
-						log.Println("Sent text reply.")
-					}
-				default:
-					log.Printf("Unsupported message content: %T\n", e.Message)
-				}
-			default:
-				log.Printf("Unsupported message: %T\n", event)
-			}
-		}
+		handler.Callback(w, req, bot, channelSecret)
 	})
 
 	// This is just sample code.