Add SysLogger for new implementation. (#17171)

This PR introduces the SysLogger to address an issue where the original Logger.py could override the SYSLOG_IDENTIFIER if a new Logger instance is created.

- Why I did it?
This change was made because the SysLog was displaying NOTICE pmon#CCmisApi: instead of NOTICE pmon#ycable:. This discrepancy led to confusion during debugging and incorrect component identification in log analysis.

- How I did it
I implemented an instance-level syslog using the logging.handlers module to prevent the SYSLOG_IDENTIFIER from being overridden.

src/sonic-py-common/sonic_py_common/daemon_base.py

@@ -1,9 +1,12 @@
+import logging
 import signal
 import sys
+import syslog
 
 from . import device_info
 from .general import load_module_from_source
 from .logger import Logger
+from .syslogger import SysLogger
 
 #
 # Constants ====================================================================
@@ -32,12 +35,16 @@ def db_connect(db_name, namespace=EMPTY_NAMESPACE):
 
 
 class DaemonBase(Logger):
-    def __init__(self, log_identifier):
-        super(DaemonBase, self).__init__(
-            log_identifier=log_identifier,
-            log_facility=Logger.LOG_FACILITY_DAEMON,
-            log_option=(Logger.LOG_OPTION_NDELAY | Logger.LOG_OPTION_PID)
-        )
+    def __init__(self, log_identifier, use_syslogger=True):
+        super().__init__()
+        if use_syslogger:
+            self.logger_instance = SysLogger(log_identifier)
+        else:
+            self.logger_instance = Logger(
+                log_identifier=log_identifier,
+                log_facility=Logger.LOG_FACILITY_DAEMON,
+                log_option=(Logger.LOG_OPTION_NDELAY | Logger.LOG_OPTION_PID)
+            )
 
         # Register our default signal handlers, unless the signal already has a
         # handler registered, most likely from a subclass implementation
@@ -48,6 +55,25 @@ def __init__(self, log_identifier):
         if not signal.getsignal(signal.SIGTERM):
             signal.signal(signal.SIGTERM, self.signal_handler)
 
+    def log(self, priority, message, also_print_to_console=False):
+        self.logger_instance.log(priority, message, also_print_to_console)
+
+    def log_error(self, message, also_print_to_console=False):
+        self.logger_instance.log_error(message, also_print_to_console)
+
+    def log_warning(self, message, also_print_to_console=False):
+        self.logger_instance.log_warning(message, also_print_to_console)
+
+    def log_notice(self, message, also_print_to_console=False):
+        self.logger_instance.log_notice(message, also_print_to_console)
+
+    def log_info(self, message, also_print_to_console=False):
+        self.logger_instance.log_info(message, also_print_to_console)
+
+    def log_debug(self, message, also_print_to_console=False):
+        self.logger_instance.log_debug(message, also_print_to_console)
+
+
     # Default signal handler; can be overridden by subclass
     def signal_handler(self, sig, frame):
         if sig == signal.SIGHUP:

src/sonic-py-common/sonic_py_common/syslogger.py

@@ -0,0 +1,62 @@
+import logging
+from logging.handlers import SysLogHandler
+import os
+import socket
+import sys
+
+class SysLogger:
+    """
+    SysLogger class for Python applications using SysLogHandler
+    """
+
+    DEFAULT_LOG_FACILITY = SysLogHandler.LOG_USER
+    DEFAULT_LOG_LEVEL = SysLogHandler.LOG_NOTICE
+
+    def __init__(self, log_identifier=None, log_facility=DEFAULT_LOG_FACILITY, log_level=DEFAULT_LOG_LEVEL):
+        if log_identifier is None:
+            log_identifier = os.path.basename(sys.argv[0])
+
+        # Initialize SysLogger
+        self.logger = logging.getLogger(log_identifier)
+
+        # Reset all existing handlers
+        for handler in self.logger.handlers[:]:
+            self.logger.removeHandler(handler)
+
+        handler = SysLogHandler(address="/dev/log", facility=log_facility, socktype=socket.SOCK_DGRAM)
+        formatter = logging.Formatter('%(name)s[%(process)d]: %(message)s')
+        handler.setFormatter(formatter)
+        self.logger.addHandler(handler)
+
+        self.set_min_log_priority(log_level)
+
+    def set_min_log_priority(self, priority):
+        """
+        Sets the minimum log priority level. All log messages
+        with a priority lower than this will not be logged
+        """
+        self._min_log_level = priority
+        self.logger.setLevel(priority)
+
+    # Methods for logging messages
+    def log(self, priority, msg, also_print_to_console=False):
+        self.logger.log(priority, msg)
+
+        if also_print_to_console:
+            print(msg)
+
+    # Convenience methods
+    def log_error(self, msg, also_print_to_console=False):
+        self.log(logging.ERROR, msg, also_print_to_console)
+
+    def log_warning(self, msg, also_print_to_console=False):
+        self.log(logging.WARNING, msg, also_print_to_console)
+
+    def log_notice(self, msg, also_print_to_console=False):
+        self.log(logging.INFO, msg, also_print_to_console)
+
+    def log_info(self, msg, also_print_to_console=False):
+        self.log(logging.INFO, msg, also_print_to_console)
+
+    def log_debug(self, msg, also_print_to_console=False):
+        self.log(logging.DEBUG, msg, also_print_to_console)

src/system-health/tests/test_system_health.py

@@ -46,9 +46,12 @@
 snmp-subagent               EXITED    Oct 19 01:53 AM
 """
 device_info.get_platform = MagicMock(return_value='unittest')
-
+ 
 device_runtime_metadata = {"DEVICE_RUNTIME_METADATA": {"ETHERNET_PORTS_PRESENT":True}}
 
+def no_op(*args, **kwargs):
+    pass  # This function does nothing
+
 def setup():
     if os.path.exists(ServiceChecker.CRITICAL_PROCESS_CACHE):
         os.remove(ServiceChecker.CRITICAL_PROCESS_CACHE)
@@ -875,7 +878,9 @@ def test_get_service_from_feature_table():
 
 
 @patch('healthd.time.time')
-def test_healthd_check_interval(mock_time):
+@patch('healthd.HealthDaemon.log_notice', side_effect=lambda *args, **kwargs: None)
+@patch('healthd.HealthDaemon.log_warning', side_effect=lambda *args, **kwargs: None)
+def test_healthd_check_interval(mock_log_warning, mock_log_notice, mock_time):
     daemon = HealthDaemon()
     manager = MagicMock()
     manager.check = MagicMock()
@@ -888,6 +893,8 @@ def test_healthd_check_interval(mock_time):
     daemon.stop_event.wait.return_value = False
     manager.config.interval = 60
     mock_time.side_effect = [0, 3, 0, 61, 0, 1]
+    mock_log_notice.side_effect = no_op
+    mock_log_warning.side_effect = no_op
     assert daemon._run_checker(manager, chassis)
     daemon.stop_event.wait.assert_called_with(57)
     assert daemon._run_checker(manager, chassis)