haproxy context based routing

http://192.168.0.228:8080/app1 => http://192.168.0.228:8081
http://192.168.0.228:8080/app2 => http://192.168.0.228:8082

haproxy.cfg

global
    daemon
    maxconn 256

defaults
    timeout connect 10s
    timeout client 30s
    timeout server 30s
    mode http
    maxconn 3000

frontend http_in
    bind *:8080
    use_backend app1_backend if { path /app1 }
    use_backend app2_backend if { path /app2 }

backend app1_backend
    http-request set-path %[path,regsub(^/app1/?,/)]
    server server1 192.168.0.228:8081

backend app2_backend
    http-request set-path %[path,regsub(^/app2/?,/)]
    server server1 192.168.0.228:8082

more : https://grafana.com/tutorials/run-grafana-behind-a-proxy/#configure-haproxy