app.js

   1 const app = new Vue({
   2     el: '#app',
   3     data: {
   4         config: null,
   5         offline: false,
   6         filter: '',
   7     },
   8     created: function () {
   9         let that = this;
  10
  11         this.checkOffline();
  12         that.getConfig().then(function (config) {
  13             that.config = config;
  14         }).catch(function () {
  15             that.offline = true;
  16         });
  17
  18         document.addEventListener('visibilitychange', function () {
  19             if (document.visibilityState == "visible") {
  20                 that.checkOffline();
  21             }
  22         }, false);
  23     },
  24     methods: {
  25         checkOffline: function () {
  26             let that = this;
  27             return fetch(window.location.href + "?alive", {
  28                 method: 'HEAD',
  29                 cache: 'no-store'
  30             }).then(function () {
  31                 that.offline = false;
  32             }).catch(function () {
  33                 that.offline = true;
  34             });
  35         },
  36         getConfig: function (event) {
  37             return fetch('config.yml').then(function (response) {
  38                 if (response.status != 200) {
  39                     return
  40                 }
  41                 return response.text().then(function (body) {
  42                     return jsyaml.load(body);
  43                 });
  44             });
  45         },
  46     }
  47 });
  48
  49 if ('serviceWorker' in navigator) {
  50     window.addEventListener('load', function () {
  51         navigator.serviceWorker.register('/worker.js');
  52     });
  53 }