The cuba-file-field component allows you to to upload files to the server.
The example below is a stub and doesn’t upload any files, so you can safely test it.
Source code:
index.html
<html>
<head>
<link rel="import" href="src/cuba/file/file-upload-app.html">
<script src="bower_components/webcomponentsjs/webcomponents-loader.js"></script>
</head>
<body>
<file-upload-app></file-upload-app>
</body>
</html>src/cuba/file/file-upload-app.html
link:../../../source/polymer-build/src/cuba/file/file-upload-app.html[role=include]