scripts: new log (#2493)

* added new `_log` function

With `_log`, the `_notify` method wa rendered obsolete. `_notify` was
not completely removed due to test failures in `check-for-changes.sh`.

The new `_log` function properly uses log levels such as `trace`,
`debug`, `info`, `warn` and `error`. It provides a cleaner solution
and renders `DMS_DEBUG` obsolete too (as only `_notify` depends on it).

* converted all helper script to new `_log` function

* converted all startup stacks to new `log` function

* `start-mailserver.sh` now uses new `_log` function

* final test and misc small script adjustments

* updated documentation

target/scripts/startup/daemons-stack.sh

@@ -2,7 +2,7 @@
 
 function start_daemons
 {
-  _notify 'tasklog' 'Starting daemons & mail server'
+  _log 'info' 'Starting daemons & mail server'
   for FUNC in "${DAEMONS_START[@]}"
   do
     ${FUNC}
@@ -11,25 +11,25 @@ function start_daemons
 
 function _start_daemons_cron
 {
-  _notify 'task' 'Starting cron'
+  _log 'debug' 'Starting cron'
   supervisorctl start cron || dms_panic__fail_init 'cron'
 }
 
 function _start_daemons_rsyslog
 {
-  _notify 'task' 'Starting rsyslog'
+  _log 'debug' 'Starting rsyslog'
   supervisorctl start rsyslog || dms_panic__fail_init 'rsyslog'
 }
 
 function _start_daemons_saslauthd
 {
-  _notify 'task' 'Starting saslauthd'
+  _log 'debug' 'Starting saslauthd'
   supervisorctl start "saslauthd_${SASLAUTHD_MECHANISMS}" || dms_panic__fail_init 'saslauthd'
 }
 
 function _start_daemons_fail2ban
 {
-  _notify 'task' 'Starting Fail2ban'
+  _log 'debug' 'Starting Fail2ban'
   touch /var/log/auth.log
 
   # delete fail2ban.sock that probably was left here after container restart
@@ -43,35 +43,35 @@ function _start_daemons_fail2ban
 
 function _start_daemons_opendkim
 {
-  _notify 'task' 'Starting opendkim'
+  _log 'debug' 'Starting opendkim'
   supervisorctl start opendkim || dms_panic__fail_init 'opendkim'
 }
 
 function _start_daemons_opendmarc
 {
-  _notify 'task' 'Starting opendmarc'
+  _log 'debug' 'Starting opendmarc'
   supervisorctl start opendmarc || dms_panic__fail_init 'opendmarc'
 }
 
 function _start_daemons_postsrsd
 {
-  _notify 'task' 'Starting postsrsd'
+  _log 'debug' 'Starting postsrsd'
   supervisorctl start postsrsd || dms_panic__fail_init 'postsrsd'
 }
 
 function _start_daemons_postfix
 {
-  _notify 'task' 'Starting postfix'
+  _log 'debug' 'Starting postfix'
   supervisorctl start postfix || dms_panic__fail_init 'postfix'
 }
 
 function _start_daemons_dovecot
 {
-  _notify 'task' 'Starting dovecot services'
+  _log 'debug' 'Starting dovecot services'
 
   if [[ ${ENABLE_POP3} -eq 1 ]]
   then
-    _notify 'task' 'Starting pop3 services'
+    _log 'debug' 'Starting pop3 services'
     mv /etc/dovecot/protocols.d/pop3d.protocol.disab \
       /etc/dovecot/protocols.d/pop3d.protocol
   fi
@@ -86,7 +86,7 @@ function _start_daemons_dovecot
 
 function _start_daemons_fetchmail
 {
-  _notify 'task' 'Preparing fetchmail config'
+  _log 'debug' 'Preparing fetchmail config'
   /usr/local/bin/setup-fetchmail
 
   if [[ ${FETCHMAIL_PARALLEL} -eq 1 ]]
@@ -119,42 +119,42 @@ EOF
     for _ in /etc/fetchmailrc.d/fetchmail-*.rc
     do
       COUNTER=$(( COUNTER + 1 ))
-      _notify 'task' "Starting fetchmail instance ${COUNTER}"
+      _log 'debug' "Starting fetchmail instance ${COUNTER}"
       supervisorctl start "fetchmail-${COUNTER}" || _panic__fail_init "fetchmail-${COUNTER}"
     done
   else
-    _notify 'task' 'Starting fetchmail'
+    _log 'debug' 'Starting fetchmail'
     supervisorctl start fetchmail || dms_panic__fail_init 'fetchmail'
   fi
 }
 
 function _start_daemons_clamav
 {
-  _notify 'task' 'Starting ClamAV'
+  _log 'debug' 'Starting ClamAV'
   supervisorctl start clamav || dms_panic__fail_init 'ClamAV'
 }
 
 function _start_daemons_postgrey
 {
-  _notify 'task' 'Starting postgrey'
+  _log 'debug' 'Starting postgrey'
   rm -f /var/run/postgrey/postgrey.pid
   supervisorctl start postgrey || dms_panic__fail_init 'postgrey'
 }
 
 function _start_daemons_amavis
 {
-  _notify 'task' 'Starting amavis'
+  _log 'debug' 'Starting amavis'
   supervisorctl start amavis || dms_panic__fail_init 'amavis'
 }
 
 function _start_changedetector
 {
-  _notify 'task' 'Starting changedetector'
+  _log 'debug' 'Starting changedetector'
   supervisorctl start changedetector || dms_panic__fail_init 'changedetector'
 }
 
 function _start_daemons_update_check
 {
-  _notify 'task' 'Starting update-check'
+  _log 'debug' 'Starting update-check'
   supervisorctl start update-check || dms_panic__fail_init 'update-check'
 }