Monitoring the custom provisioning process of a droplet

I’m setting up a service that requires automatically creating droplets and running a fairly lengthy provisioning process, supplied as a bash script in the user data parameter. I’ve found that this process can vary significantly, taking as little as three or as many as ten minutes. To be able to show users that progress is being made and to detect problems, I’d like to be able to monitor the provisioning and know what step it’s at.

A large component of my service is Nginx which is just functioning as a reverse proxy so I can use SSL/TLS. This is currently in the middle of the script, but I could easily move it to the front so almost immediately I’d have a way of responding to HTTP requests. Then, I could just configure a route to serve the contents of a txt file, which my script could echo messages into as it goes through the provisioning steps.

This is one way that might work but I haven’t attempted it yet, so I wanted to post here to see if there are better ways to do this sort of thing.