Bug fix: Save fingerprint.

Bug fix: Show error whey device isn't plugged.

public/app.js

@@ -34,6 +34,12 @@ var app = new Vue({
 
         this.socket.on("connect", () => { })
 
+        this.socket.on("fprint-enroll-error", (data) => {
+            console.log({ event: 'enroll-error', data });
+            swal("Oops!", `Operation failed. ${data}.`, "error");
+            this.busy.login = false;
+        });
+
         this.socket.on("fprint-enroll-done", (data) => {
             console.log({ event: 'enroll-done', data});
             if (data.ok) {
@@ -102,10 +108,10 @@ var app = new Vue({
         saveFingerPrint: async function () {
             this.busy.login = true;
             try {
-                var fingerprints = Object.keys(this.fingerprints).map(finger => {
+                var fingerprints = Object.keys(this.fingerDetails).map(finger => {
                     return {
                         finger,
-                        fingerprint: this.fingerprints[finger]
+                        fingerprint: this.fingerDetails[finger]
                     }
                 });
                 var { data } = await axios.post(