Frontend is using the backend URL as OMR_SERVICE_URI=https://example.com/mat/api/v1.
We are constructing a ALB on AWS to expose only the web endpoint. We specified Registered target as AWS EC2 instance in which the backend service is running.
We also passed the Listner rules with /mat/* by using Security Groups so that access to the backend service endpoint is successful.
We are aware that OMR_SERVICE_URI is opened, and the URL can be accessed from internet.
How can we prevent access to the backend service from internet, when the web application is accessed via ALB.