haproxy: set timeout if <condition> - haproxy

Question

The question seems to be quite straight and easy, however I have not been able to find a proper answer.
In haproxy I have 1 backend, say:
backend-1
and 2 frontends, say:
frontend-1
frontend-2
In the backend stanza I want to set a "timeout server" parameter, but, only if the connection comes from frontend-1.
As I didn't find anything I tried to figure it out myself:
backend backend-1
bind *:80
option <blahblah_option>
timeout server 1d if frontend frontend-1
This syntax does not work, and I am mentioning it to let understand what I am trying to achieve.

Answer 1

This is not doable yet in HAProxy.
Later, you will be able to set timeouts using tcp-request and http-request rules.
What we usually do to workaround this for now, is that we setup 2 backends using the same parameters, but different timeout servers.
This is useful when a few urls only deserve a long server timeout.
Edit followup your comment about multiple health checks:
Well, that's why the server's 'track' directive exists:
backend my_app
server srv1 10.0.0.1:80 check
backend my_app_longtime
server srv1 10.0.0.1:80 track my_app/srv1
In the conf above, the server in my_app_longtime backend won't be checked. That said, it will follow up the same state than srv1 in the backend my_app.
Baptiste
Baptiste

Answer 2

I did it like this and it worked. It made it possible to extend timeout on specific app urls, which are more time consuming. Used that trace health check - thanks Babtiste.
frontend www-http
bind 10.0.0.1:80
default_backend app
acl long_url path_beg -i /long_url
use_backend app-extended if long_url
backend app
server web-1 10.0.0.2:80 check
backend app-extended
server web-1 10.0.0.2:80 trace app/web-1
timeout server 10m