Add this entries to /etc/hosts:

test1.local 127.0.0.1
test2.local 127.0.0.1
test3.local 127.0.0.1

Open 3 terminals:

Terminal One:

cd hrt-reverse-proxy
cargo run
....
LISTEN on 127.0.0.1:13900

Terminal Two:

# test1.local
cd hrt-reverse-proxy/html
php -S localhost:13901

Terminal Three:

curl -L -X GET http://test1.local:13900

And you will see that the request will be redirected according to your host.

Go to config/config.json and change your configuration to your needs. You can redirect request by host header or by path. There are no other options for now. You can change the bind address and port to your needs. If port is 80, it must be run as root. For example, if you want to redirect mysite.com to localhost:8080, you will write this in config/config.json:

{
    "bind_to_host": "127.0.0.1",
    "bind_to_port": "80",
    "routes": [
        {
            "match": "mysite.com",
            "type": {
                "what": "header"
            },
            "forward_to": "http://localhost:8080"
        }
    ]
}

cargo build --release