I am looking for a quick way to spin up a very simple REST api, for testing purposes.
Specifically I want to be able to handle CORS preflight requests (i.e need ability to handle the OPTIONS verb)
E.g: A service that spins up a temporary node instance with express and allows me to add request handlers and gives me a temporary url. Or the equivalent in another language (java, ruby, etc)
Maybe try https://code.runnable.com it allows you to quickly build and run whole express apps and it allows multiple different languages not just node.js.
Edit: this website has been sunset, https://replit.com is a decent place now to sandbox/playground with different languages.