Monitor rsyslog feature flag change and update rsyslog config by restart rsyslog-config service

scripts/hostcfgd

@@ -1423,6 +1423,7 @@ class DeviceMetaCfg(object):
     def __init__(self):
         self.hostname = ''
         self.timezone = None
+        self.syslog_with_osversion = None
 
     def load(self, dev_meta={}):
         # Get hostname initial
@@ -1431,6 +1432,7 @@ class DeviceMetaCfg(object):
 
         # Load appropriate config
         self.timezone = dev_meta.get('localhost', {}).get('timezone')
+        self.syslog_with_osversion = dev_meta.get('localhost', {}).get('syslog_with_osversion')
 
     def hostname_update(self, data):
         """
@@ -1491,6 +1493,32 @@ class DeviceMetaCfg(object):
         syslog.syslog(syslog.LOG_INFO, 'DeviceMetaCfg: Restart rsyslog after '
                       'changing timezone')
 
+    def rsyslog_config(self, data):
+        """
+        Apply syslog_with_osversion feature flag.
+        Run the following command in Linux: sudo systemctl restart rsyslog-config
+        Args:
+            data: Read table's key's data.
+        """
+        new_syslog_with_osversion = data.get('syslog_with_osversion')
+        syslog.syslog(syslog.LOG_DEBUG,
+                      f'DeviceMetaCfg: syslog with os version: {new_syslog_with_osversion}')
+
+        if new_syslog_with_osversion is None:
+            syslog.syslog(syslog.LOG_DEBUG,
+                          f'DeviceMetaCfg: syslog with os version feature disabled')
+            return
+
+        if new_syslog_with_osversion == self.syslog_with_osversion:
+            syslog.syslog(syslog.LOG_DEBUG,
+                          f'DeviceMetaCfg: syslog with os version feature flag does not change')
+            return
+
+        run_cmd(['systemctl', 'restart', 'rsyslog-config'], True, False)
+        syslog.syslog(syslog.LOG_INFO, 'DeviceMetaCfg: Restart rsyslog-config after '
+                                        'feature flag change to {}'.format(new_syslog_with_osversion))
+
+
 class MgmtIfaceCfg(object):
     """
     MgmtIfaceCfg Config Daemon
@@ -2281,6 +2309,7 @@ class HostConfigDaemon:
         syslog.syslog(syslog.LOG_INFO, 'DeviceMeta handler...')
         self.devmetacfg.hostname_update(data)
         self.devmetacfg.timezone_update(data)
+        self.devmetacfg.rsyslog_config(data)
 
     def rsyslog_handler(self):
         rsyslog_config = self.config_db.get_table(

tests/hostcfgd/hostcfgd_test.py

@@ -247,6 +247,7 @@ def test_devicemeta_event(self):
         Test handling DEVICE_METADATA events.
         1) Hostname reload
         1) Timezone reload
+        1) syslog_with_osversion flag change
         """
         MockConfigDb.set_config_db(HOSTCFG_DAEMON_CFG_DB)
         MockConfigDb.event_queue = [(swsscommon.CFG_DEVICE_METADATA_TABLE_NAME,
@@ -306,6 +307,22 @@ def test_devicemeta_event(self):
                 ]
                 mocked_syslog.syslog.assert_has_calls(expected)
 
+        daemon.devmetacfg.syslog_with_osversion = "false"
+        HOSTCFG_DAEMON_CFG_DB["DEVICE_METADATA"]["localhost"]["syslog_with_osversion"] = 'true'
+        MockConfigDb.set_config_db(HOSTCFG_DAEMON_CFG_DB)
+        with mock.patch('hostcfgd.syslog') as mocked_syslog:
+            with mock.patch('hostcfgd.subprocess') as mocked_subprocess:
+                mocked_syslog.LOG_INFO = original_syslog.LOG_INFO
+                try:
+                    daemon.start()
+                except TimeoutError:
+                    pass
+
+                expected = [
+                    call(original_syslog.LOG_INFO, 'DeviceMetaCfg: Restart rsyslog-config after feature flag change to true')
+                ]
+                mocked_syslog.syslog.assert_has_calls(expected)
+
     def test_mgmtiface_event(self):
         """
         Test handling mgmt events.