This is a small application that illustrates how to use CORS, Manta signed URLs and Ajax in order to upload files directly to Manta. Doing this allows you to bypass your own servers to save on bandwidth.
The only dependency this application has is manta:
npm install manta
Then
npm start
Will get you going. Point your browser at http://127.0.0.1:1234.
There are really two parts to this: the server and "webapp". In this particular example, the webapp is a very simple single page, that does rely on JQuery. The code is all commented, but the basic gist is:
BSD, I guess, because that's the npm default. Honestly, I don't really care. Do whatever you want with this.