defaults: T6989: provide single source of systemd services

Some systemd services are re-used over multiple configuration files. Keep a
single source of the real systemd names and only reference them by dictionary
keys.

python/vyos/defaults.py

@@ -1,4 +1,4 @@
-# Copyright 2018-2024 VyOS maintainers and contributors <[email protected]>
+# Copyright 2018-2025 VyOS maintainers and contributors <[email protected]>
 #
 # This library is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -40,6 +40,11 @@
   'ca_certificates' : '/usr/local/share/ca-certificates/vyos'
 }
 
+systemd_services = {
+    'rsyslog' : 'rsyslog.service',
+    'snmpd' : 'snmpd.service',
+}
+
 config_status = '/tmp/vyos-config-status'
 api_config_state = '/run/http-api-state'
 frr_debug_enable = '/tmp/vyos.frr.debug'

src/conf_mode/service_snmp.py

@@ -22,6 +22,7 @@
 from vyos.config import Config
 from vyos.configdict import dict_merge
 from vyos.configverify import verify_vrf
+from vyos.defaults import systemd_services
 from vyos.snmpv3_hashgen import plaintext_to_md5
 from vyos.snmpv3_hashgen import plaintext_to_sha1
 from vyos.snmpv3_hashgen import random
@@ -43,7 +44,7 @@
 config_file_user    = r'/var/lib/snmp/snmpd.conf'
 default_script_dir  = r'/config/user-data/'
 systemd_override    = r'/run/systemd/system/snmpd.service.d/override.conf'
-systemd_service     = 'snmpd.service'
+systemd_service     = systemd_services['snmpd']
 
 def get_config(config=None):
     if config:

src/conf_mode/system_host-name.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 #
-# Copyright (C) 2018-2024 VyOS maintainers and contributors
+# Copyright (C) 2018-2025 VyOS maintainers and contributors
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 2 or later as
@@ -23,6 +23,7 @@
 from vyos.base import Warning
 from vyos.config import Config
 from vyos.configdict import leaf_node_changed
+from vyos.defaults import systemd_services
 from vyos.ifconfig import Section
 from vyos.template import is_ip
 from vyos.utils.process import cmd
@@ -174,11 +175,13 @@ def apply(config):
 
     # Restart services that use the hostname
     if hostname_new != hostname_old:
-        call("systemctl restart rsyslog.service")
+        tmp = systemd_services['rsyslog']
+        call(f'systemctl restart {tmp}')
 
     # If SNMP is running, restart it too
     if process_named_running('snmpd') and config['snmpd_restart_reqired']:
-        call('systemctl restart snmpd.service')
+        tmp = systemd_services['snmpd']
+        call(f'systemctl restart {tmp}')
 
     return None
 

src/conf_mode/system_syslog.py

@@ -22,6 +22,7 @@
 from vyos.config import Config
 from vyos.configdict import is_node_changed
 from vyos.configverify import verify_vrf
+from vyos.defaults import systemd_services
 from vyos.utils.network import is_addr_assigned
 from vyos.utils.process import call
 from vyos.template import render
@@ -34,6 +35,9 @@
 rsyslog_conf = '/run/rsyslog/rsyslog.conf'
 logrotate_conf = '/etc/logrotate.d/vyos-rsyslog'
 
+systemd_socket = 'syslog.socket'
+systemd_service = systemd_services['rsyslog']
+
 def get_config(config=None):
     if config:
         conf = config
@@ -111,8 +115,6 @@ def generate(syslog):
     return None
 
 def apply(syslog):
-    systemd_socket = 'syslog.socket'
-    systemd_service = 'syslog.service'
     if not syslog:
         call(f'systemctl stop {systemd_service} {systemd_socket}')
         return None