Generic redirect from api.site.com/service/{domain} to other servers

Help!
1

We have nginx server that redirect service requests by server name using proxy pass to upstream:

nginx conf:

server {
server_name requestsproxy-rest.us.example.com;
…
location / {
…
proxy_pass http://Requestsproxy-Rest;

and the upstream file:

least_conn;
server 10.1.1.1:29257 max_fails=4 fail_timeout=1s weight=1;

server 10.1.1.2:21591 max_fails=4 fail_timeout=1s weight=1;

}

We want to create haproxy that service(service) to be able to be accessed via “test.example.com/service/{service}” and the haproxy will forward/redirect the request to different address by the {service} to the nginx.

how do you think we can manage it via haproxy configurations?

Thanks in advanced.