Wait Until Up

Install npm i -g wuu

Then you can use this in shell scripts, like so

# /bin/bash
wuu --port 5672 --host rabbitmq --timeout 60 --retry 2
wuu --port 5432 --host postgres --timeout 60 --retry 2

# ok rabbit and postgres running
node ./server.js

Or use in a node script:

const wuu = require('wuu')
wuu(port, host, retry, timeout).then(() => {
	// that thing is listening
})