How can application on S3 can connect to internal load balancer on private subnet

Question

My application js (SPA) hosted to S3 with public access, and setup EC2 in private subnet with internal load balancer on AWS (can't access by public).

Question: How can application on S3 can connect to internal load balancer on private subnet?

Answer 1

I can say: it's impossible.

Your SPA is client side (browser) running. So, you need kind of public endpoint.

Answer 2

I agree with @Tuan VA, It's impossible what you are asking.

if you want a public website

you need a public load balancer for your EC2

if you want to make your website internal and available only via VPN or direct connect to your on-premise employees.

you can make sure website private as described below:

1. Set up the static website as normal,
2. Add a VPC endpoint for S3,
3. Use a bucket policy to deny all but traffic from your VPC