Ngrok Spring Boot Starter makes establishing a tunnel towards your developer machine as easy as adding a dependency to your Spring Boot project.
Ngrok is a tool for creating a secure tunnel from the public web to a machine behind a NAT or a firewall. It is considered the gold standard. Specifically it is used for exposing your local developer machine to the public net in order to test your projects or benchmark them. This is especially useful for quick prototypes, proof of concept or demonstration purposes. Also a type of tools, for instance Pingdom Website Testing, need to access your web project only over a public Internet addresses. So one such a way is to open a channel between your localhost and a public Internet address so that it can be accessed by all those services.
But since you are developer who is reading this, there's a very good chance that you own a VPS on Digital Ocean or Linode or elsewhere and can set up a reverse proxy on your local machine without needing ngrok at all. This setup is possible but you have to manually configure:
full article on i-programmer: