[Rspamd-Users] Problems figuring out syntax for "settings_id"

[Ed W]

Hi, new user, very impressed with rspamd, but, I'm not able to figure 
out how to use "settings_id" in a milter rspamd-proxy to select a 
different set of "settings"?

My requirement is that from Postfix I need to choose between two 
scanning scenarios, the extra scenario is dkim signing only. I cannot 
see a way to pass a settings_id from postfix (perhaps there is something 
I overlooked?), so instead I tried to setup a second rspamd_proxy 
listening on a different port and then I have postfix talk to the other 
port as necessary (via milter). rspamd version is 1.8.3


Config:

#local.d/settings:

dkim {
     priority = high;
     id = "dkim";

     apply {
         symbols_enabled = ["DKIM_SIGNED"];
         flags = ["skip_process"]; # To skip message processing
     }
}


# rspamd.conf.local (created a new worker process)

# Worker setup for DKIM only processing
worker "rspamd_proxy" {
     bind_socket = "*:11331";
     .include "$CONFDIR/worker-proxy.inc"

     upstream "local" {
         self_scan = yes; # Enable self-scan
         # Override settings.conf and apply "dkim_only" settings section
         settings_id = "dkim";
     }
}


This seems to work as expected if I use (through another worker, not via 
milter)

     rspamc --header="settings-id=dkim"


But sending via my milter I see no evidence that the settings takes 
effect, eg no mention of "applying settings id dkim" change in the logs, 
the scan logs for the email include extra symbols, etc.

I am reasonably sure the postfix side is setup correctly (eg disabling 
the extra worker gives "cannot connect" type errors. Likewise the 
settings seem to behave as expected when I pass the header via rpamc. So 
I think that I have something wrong with my syntax in the worder file?

I'm following the documentation linked below. There it's not clear what 
should used for the settings_id? It uses a number in the examples(?), 
but looking at the code implies it should be the same text I use with 
--header?

https://rspamd.com/doc/faq.html#how-to-distinguish-inbound-and-outbound-traffic-for-rspamd-instance


Any tips on what I'm doing wrong?

Thanks

Ed W