Display server started notification on first client

app/i18n/en.json

@@ -118,5 +118,6 @@
   "MANDATORY_SECURITY_QUESTION": "Please select a security question.",
   "MANDATORY_SECURITY_ANSWER": "Please provide an answer to your security question.",
   "FORGOT_PASSWORD": "Forgot your password?",
-  "TITLE_FORGOT_PASSWORD": "Forgot Password"
+  "TITLE_FORGOT_PASSWORD": "Forgot Password",
+  "NOTIFICATION_SERVER_STARTED": "The server has been restarted! Your hacking progress has been restored automatically."
 }

app/index.template.html

@@ -142,6 +142,12 @@
 
 <h1 class="hidden" ng-bind="applicationName"></h1><!-- for SEO -->
 
+<div class="container" ng-controller="ServerStartedNotificationController">
+    <div uib-alert ng-show="serverStartedMessage" ng-class="'alert alert-warning'" close="closeNotification()">
+        {{serverStartedMessage}}
+    </div>
+</div>
+
 <div class="container" ng-controller="ChallengeSolvedNotificationController">
     <div uib-alert ng-repeat="notification in notifications" ng-class="'alert alert-success'" close="closeNotification($index)">
         {{notification.message}}<br>

app/js/controllers/ServerStartedNotificationController.js

@@ -0,0 +1,30 @@
+angular.module('juiceShop').controller('ServerStartedNotificationController', [
+  '$scope',
+  '$translate',
+  '$cookies',
+  'ChallengeService',
+  'socket',
+  function ($scope, $translate, $cookies, challengeService, socket) {
+    'use strict'
+
+    $scope.closeNotification = function () {
+      $scope.serverStartedMessage = null
+    }
+
+    socket.on('server started', function () {
+      var continueCode = $cookies.get('continueCode')
+      console.log(continueCode)
+      if (continueCode) {
+        challengeService.restoreProgress(encodeURIComponent(continueCode)).then(function () {
+          $cookies.remove('continueCode')
+          $translate('NOTIFICATION_SERVER_STARTED').then(function (notificationServerStarted) {
+            $scope.serverStartedMessage = notificationServerStarted
+          }, function (translationId) {
+            $scope.serverStartedMessage = translationId
+          })
+        }).catch(function (error) {
+          console.log(error)
+        })
+      }
+    })
+  } ])

server.js

@@ -50,6 +50,7 @@ var io = require('socket.io')(server)
 var replace = require('replace')
 var appConfiguration = require('./routes/appConfiguration')
 const config = require('config')
+var firstConnectedSocket = null
 
 global.io = io
 errorhandler.title = 'Juice Shop (Express ' + utils.version('express') + ')'
@@ -188,6 +189,12 @@ app.use(verify.errorHandlingChallenge())
 app.use(errorhandler())
 
 io.on('connection', function (socket) {
+  // notify only first client to connect about server start
+  if (firstConnectedSocket === null) {
+    socket.emit('server started')
+    firstConnectedSocket = socket.id
+  }
+
   // send all outstanding notifications on (re)connect
   notifications.forEach(function (notification) {
     socket.emit('challenge solved', notification)