test m4 change 3

Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.23.3
+FROM alpine:3.23.2
 
 LABEL Maintainer="Wolfgang Hottgenroth <woho@hottis.de>"
 LABEL ImageName="quay.io/wollud1969/exim-docker"

exim.conf.m4

@@ -8,11 +8,6 @@ define(`RELAYNETS', esyscmd(`echo -n $RELAYNETS'))dnl
 define(`WHITELISTED_RECIPIENTS', esyscmd(`echo -n $WHITELISTED_RECIPIENTS'))dnl
 
 
-ifelse(SMARTHOST, `', `
-errprint(`Error: SMARTHOST not set')
-m4exit(1)
-')
-
 ifelse(HOSTNAME, `', `
 errprint(`Error: HOSTNAME not set')
 m4exit(1)
@@ -28,6 +23,20 @@ acl_smtp_rcpt = acl_check_rcpt
 
 tls_advertise_hosts =
 
+ifelse(SMARTHOST, `', `dnl
+# without smarthost
+begin routers
+dnslookup:
+  driver = dnslookup
+  domains = *
+  transport = remote_smtp
+
+begin transports
+remote_smtp:
+  driver = smtp
+
+', `dnl
+# with smarthost
 begin routers
 smarthost_route:
   driver = manualroute
@@ -56,6 +65,7 @@ login:
   public_name = LOGIN
   client_send = : SMARTHOST_USER : SMARTHOST_PASS
 ')
+')
 
 begin acl
 acl_check_rcpt:

readme.md

@@ -15,6 +15,8 @@ Four environment variables are used to configure the container:
 * `WHITELISTED_RECIPIENT`: Colon-separated list of whitelisted recipient domains, if empty no recipient restrictions will be applied
 
 
+If `SMARTHOST` is not given, mail delivery will be done directly via MX lookup instead of using a smarthost.
+
 ## Deployment
 
 Typically, don't expose the smtp port of this container to the default network of your Docker installation, otherwise it conflicts with a local MTA on the machine and it would be visible outside of the machine. Create a dedicated docker network, use that one as the default network for this container and connect other containers to that network. Afterwards, you can use the name of this container as smarthost address in the other containers.