Disable Node.js integration

See https://www.electronjs.org/docs/tutorial/security#2-do-not-enable-nodejs-integration-for-remote-content

Author: hidakatsuya

app/handlers.js

@@ -99,4 +99,4 @@ handlers.exportAs = (callback, type, content) => {
   callback.onSuccess();
 }
 
-module.exports = handlers;
+window.handlers = handlers;

app/index.js

@@ -15,7 +15,7 @@
 
 var App = {};
 
-App.handlers = require('./handlers');
+App.handlers = window.handlers;
 
 /**
  * @type {string}

app/main.js

@@ -7,13 +7,14 @@ process.env.NODE_ENV = process.env.NODE_ENV || 'production'
 let win
 
 function createWindow () {
+  console.log(app.getAppPath());
   win = new BrowserWindow({
     width: 1000,
     height: 700,
     icon: path.join(__dirname, 'assets/images/app-icon.png'),
     webPreferences: {
-      nodeIntegration: true,
-      enableRemoteModule: true
+      enableRemoteModule: true,
+      preload: path.join(__dirname, 'handlers.js')
     }
   })