Python with the Flask framework is great, very easy to do the API endpoints. The whole app can fit in one .py file of about four lines plus 3 per endpoint, see the sample at http://flask.pocoo.org/.

You can host it on Heroku in their free tier of service if it's just for testing. That includes a PostgreSQL instance if you want one.

I don't know much Javascript but with the Flask framework, all HTML/JS/CSS files are static templates that sit in a folder with your app's code. You can deploy with Git or even with Dropbox if you want it on super easy mode.