From 9546c98ce8f5d2dc2ab6b676b49dde4d44e9f759 Mon Sep 17 00:00:00 2001
From: peterstone2017 <12449837+YunchuWang@users.noreply.github.com>
Date: Mon, 23 Sep 2024 15:48:56 -0700
Subject: [PATCH 1/3] feat: add sigterm handler to gracefully shutdown worker
 and log

---
 azure_functions_worker/logging.py |  3 +++
 azure_functions_worker/main.py    | 44 +++++++++++++++++++++++++++++++
 2 files changed, 47 insertions(+)

diff --git a/azure_functions_worker/logging.py b/azure_functions_worker/logging.py
index adb5ff294..7a0bbea0c 100644
--- a/azure_functions_worker/logging.py
+++ b/azure_functions_worker/logging.py
@@ -91,6 +91,9 @@ def enable_console_logging() -> None:
     if logger and handler:
         logger.addHandler(handler)
 
+def flush_logger(logger: logging.Logger):
+    for handler in logger.handlers:
+        handler.flush()
 
 def is_system_log_category(ctg: str) -> bool:
     """Check if the logging namespace belongs to system logs. Category starts
diff --git a/azure_functions_worker/main.py b/azure_functions_worker/main.py
index 130e0e9ea..eff874aa9 100644
--- a/azure_functions_worker/main.py
+++ b/azure_functions_worker/main.py
@@ -47,12 +47,16 @@ def main():
 
     import asyncio
 
+
     from . import logging
     from .logging import error_logger, format_exception, logger
 
     args = parse_args()
     logging.setup(log_level=args.log_level, log_destination=args.log_to)
 
+    # register sigterm handler
+    register_sigterm_handler()
+
     logger.info('Starting Azure Functions Python Worker.')
     logger.info('Worker ID: %s, Request ID: %s, Host Address: %s:%s',
                 args.worker_id, args.request_id, args.host, args.port)
@@ -66,6 +70,46 @@ def main():
                 format_exception(ex)))
         raise
 
+def register_sigterm_handler():
+    import signal
+    """
+    Registers a custom handler for the SIGTERM signal.
+
+    This function will set up a signal handler to intercept the SIGTERM signal,
+    which is typically sent to gracefully terminate a process. When SIGTERM is
+    received, the program will log the signal and perform a graceful shutdown
+    by calling sys.exit().
+
+    Windows Python Function is not supported and Windows does not support
+    SIGTERM.
+    """
+
+    def handle_sigterm(signum, frame):
+        from . import dispatcher
+        import sys
+        from .logging import logger, flush_logger
+        import traceback
+        from azure_functions_worker.dispatcher import DispatcherMeta
+        from azure_functions_worker import loader
+        # Log the received signal
+        logger.info(f"SIGTERM received (signal: {signum}). "
+                    "Shutting down gracefully...")
+        
+        # Log the frame details to see whats executed when the signal was received
+        logger.info("Frame details at signal receipt:"
+                     f"\n{''.join(traceback.format_stack(frame))}")
+
+        DispatcherMeta.__current_dispatcher__ = None
+
+        loader.uninstall()
+
+        flush_logger()
+
+        dispatcher.Dispatcher.stop()
+        sys.exit(0)  # Exit the program gracefully
+
+    signal.signal(signal.SIGTERM, handle_sigterm)
+
 
 async def start_async(host, port, worker_id, request_id):
     from . import dispatcher

From c31581043fc7914bac44b28b5799122c101355a7 Mon Sep 17 00:00:00 2001
From: peterstone2017 <12449837+YunchuWang@users.noreply.github.com>
Date: Mon, 23 Sep 2024 15:50:13 -0700
Subject: [PATCH 2/3] fix: flush_logger

---
 azure_functions_worker/main.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/azure_functions_worker/main.py b/azure_functions_worker/main.py
index eff874aa9..1738d6d24 100644
--- a/azure_functions_worker/main.py
+++ b/azure_functions_worker/main.py
@@ -103,7 +103,7 @@ def handle_sigterm(signum, frame):
 
         loader.uninstall()
 
-        flush_logger()
+        flush_logger(logger)
 
         dispatcher.Dispatcher.stop()
         sys.exit(0)  # Exit the program gracefully

From 98f6ac13d23db0919aaec43f59bb53f5ce03265b Mon Sep 17 00:00:00 2001
From: wangbill <12449837+YunchuWang@users.noreply.github.com>
Date: Tue, 24 Sep 2024 09:29:46 -0700
Subject: [PATCH 3/3] fix: linting

---
 azure_functions_worker/logging.py | 2 ++
 azure_functions_worker/main.py    | 6 +++---
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/azure_functions_worker/logging.py b/azure_functions_worker/logging.py
index 7a0bbea0c..a7aaae9c3 100644
--- a/azure_functions_worker/logging.py
+++ b/azure_functions_worker/logging.py
@@ -91,10 +91,12 @@ def enable_console_logging() -> None:
     if logger and handler:
         logger.addHandler(handler)
 
+
 def flush_logger(logger: logging.Logger):
     for handler in logger.handlers:
         handler.flush()
 
+
 def is_system_log_category(ctg: str) -> bool:
     """Check if the logging namespace belongs to system logs. Category starts
     with the following name will be treated as system logs.
diff --git a/azure_functions_worker/main.py b/azure_functions_worker/main.py
index 1738d6d24..b2a7d237d 100644
--- a/azure_functions_worker/main.py
+++ b/azure_functions_worker/main.py
@@ -47,7 +47,6 @@ def main():
 
     import asyncio
 
-
     from . import logging
     from .logging import error_logger, format_exception, logger
 
@@ -70,6 +69,7 @@ def main():
                 format_exception(ex)))
         raise
 
+
 def register_sigterm_handler():
     import signal
     """
@@ -94,10 +94,10 @@ def handle_sigterm(signum, frame):
         # Log the received signal
         logger.info(f"SIGTERM received (signal: {signum}). "
                     "Shutting down gracefully...")
-        
+
         # Log the frame details to see whats executed when the signal was received
         logger.info("Frame details at signal receipt:"
-                     f"\n{''.join(traceback.format_stack(frame))}")
+                    f"\n{''.join(traceback.format_stack(frame))}")
 
         DispatcherMeta.__current_dispatcher__ = None