From 87efdddf0c2e1390e81732d6ed8bcc817a84fa42 Mon Sep 17 00:00:00 2001
From: Dylan Russell <dylanrus@gmail.com>
Date: Fri, 13 Jun 2025 19:54:12 +0000
Subject: [PATCH 01/13] Fix deadlock bug

---
 .../sdk/_logs/_internal/__init__.py           |  4 ++-
 opentelemetry-sdk/tests/logs/test_handler.py  | 28 +++++++++++++++++++
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py
index 8c0be234508..11a2c7fd64e 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py
@@ -489,6 +489,7 @@ def __init__(
     ) -> None:
         super().__init__(level=level)
         self._logger_provider = logger_provider or get_logger_provider()
+        # self.flushOnClose = False
 
     @staticmethod
     def _get_attributes(record: logging.LogRecord) -> _ExtendedAttributes:
@@ -584,7 +585,8 @@ def flush(self) -> None:
         if hasattr(self._logger_provider, "force_flush") and callable(
             self._logger_provider.force_flush
         ):
-            self._logger_provider.force_flush()
+            thread = threading.Thread(target=self._logger_provider.force_flush)
+            thread.start()
 
 
 class Logger(APILogger):
diff --git a/opentelemetry-sdk/tests/logs/test_handler.py b/opentelemetry-sdk/tests/logs/test_handler.py
index 3817c440258..157dde649dd 100644
--- a/opentelemetry-sdk/tests/logs/test_handler.py
+++ b/opentelemetry-sdk/tests/logs/test_handler.py
@@ -59,6 +59,34 @@ def test_handler_custom_log_level(self):
             logger.critical("No Time For Caution")
         self.assertEqual(processor.emit_count(), 2)
 
+    def test_handler_calling_flush_does_not_cause_deadlock(self):
+        class LogProcessorThatAccessesLockOnFlush(LogRecordProcessor):
+            def emit(self, log_data: LogData):
+                pass
+
+            def shutdown(self):
+                pass
+
+            def force_flush(self, timeout_millis: int = 30000):
+                # Deadlock will happen here IF `flush` starts a new thread
+                # and then blocks, if it just starts a thread and then returns
+                # we don't seem to encounter the issue..
+                logging._lock.acquire()
+                # assert logging._lock.acquire(False) is True
+                logging._lock.release()
+
+        logger_provider = LoggerProvider()
+        processor = LogProcessorThatAccessesLockOnFlush()
+        logger_provider.add_log_record_processor(processor)
+        handler = LoggingHandler(logger_provider=logger_provider)
+        logging.getLogger().addHandler(handler)
+        # The below code is essentially recreating what is causing the problem inside
+        # logging.config.dictConfig. Actually calling logging.config.dictConfig will modify
+        # global state inside the logging module and break lots of tests.
+        with logging._lock:
+            for handler in logging.getLogger().handlers:
+                handler.flush()
+
     # pylint: disable=protected-access
     def test_log_record_emit_noop(self):
         noop_logger_provder = NoOpLoggerProvider()

From c45220472939bef31cceddd4c7e5ac25b6cd0935 Mon Sep 17 00:00:00 2001
From: Dylan Russell <dylanrus@gmail.com>
Date: Wed, 25 Jun 2025 13:29:24 +0000
Subject: [PATCH 02/13] Overwrite logging config functions with patched
 versions..

---
 .../sdk/_configuration/__init__.py            | 41 +++++++-------
 opentelemetry-sdk/tests/test_configurator.py  | 56 ++++++++++++++++++-
 2 files changed, 76 insertions(+), 21 deletions(-)

diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
index 745a83385f9..85080284273 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
@@ -20,6 +20,7 @@
 from __future__ import annotations
 
 import logging
+import logging.config
 import os
 from abc import ABC, abstractmethod
 from os import environ
@@ -253,31 +254,31 @@ def _init_logging(
     set_event_logger_provider(event_logger_provider)
 
     if setup_logging_handler:
-        _patch_basic_config()
-
         # Add OTel handler
         handler = LoggingHandler(
             level=logging.NOTSET, logger_provider=provider
         )
         logging.getLogger().addHandler(handler)
-
-
-def _patch_basic_config():
-    original_basic_config = logging.basicConfig
-
-    def patched_basic_config(*args, **kwargs):
-        root = logging.getLogger()
-        has_only_otel = len(root.handlers) == 1 and isinstance(
-            root.handlers[0], LoggingHandler
-        )
-        if has_only_otel:
-            otel_handler = root.handlers.pop()
-            original_basic_config(*args, **kwargs)
-            root.addHandler(otel_handler)
-        else:
-            original_basic_config(*args, **kwargs)
-
-    logging.basicConfig = patched_basic_config
+        _overwrite_logging_config_fns(handler)
+
+
+def _overwrite_logging_config_fns(handler):
+    root = logging.getLogger()
+
+    def wrapper(config_fn):
+        def overwritten_config_fn(*args, **kwargs):
+            # This is needed for basicConfig only. basicConfig when called by
+            # the user's program will be a no-op if the root handler was configured.
+            if len(root.handlers) == 1 and root.handlers[0] == handler:
+                root.handlers.pop()
+            config_fn(*args, **kwargs)
+            if handler not in root.handlers:
+                root.addHandler(handler)
+        return overwritten_config_fn
+
+    logging.config.fileConfig = wrapper(logging.config.fileConfig)
+    logging.config.dictConfig = wrapper(logging.config.dictConfig)
+    logging.basicConfig = wrapper(logging.basicConfig)
 
 
 def _import_exporters(
diff --git a/opentelemetry-sdk/tests/test_configurator.py b/opentelemetry-sdk/tests/test_configurator.py
index 9fda75b66f0..c13123828fc 100644
--- a/opentelemetry-sdk/tests/test_configurator.py
+++ b/opentelemetry-sdk/tests/test_configurator.py
@@ -16,12 +16,14 @@
 from __future__ import annotations
 
 import logging
+import logging.config
 from logging import WARNING, getLogger
 from os import environ
 from typing import Iterable, Optional, Sequence
 from unittest import TestCase, mock
 from unittest.mock import Mock, patch
 
+import pytest
 from pytest import raises
 
 from opentelemetry import trace
@@ -881,7 +883,6 @@ def test_basicConfig_preserves_otel_handler(self):
             )
             handler = root_logger.handlers[0]
             self.assertIsInstance(handler, LoggingHandler)
-
             logging.basicConfig()
 
             self.assertGreater(len(root_logger.handlers), 1)
@@ -897,6 +898,51 @@ def test_basicConfig_preserves_otel_handler(self):
                 "Should still have exactly one OpenTelemetry LoggingHandler",
             )
 
+    def test_dictConfig_preserves_otel_handler(self):
+        with ClearLoggingHandlers():
+            _init_logging(
+                {"otlp": DummyOTLPLogExporter},
+                Resource.create({}),
+                setup_logging_handler=True,
+            )
+
+            root = logging.getLogger()
+            self.assertEqual(
+                len(root.handlers),
+                1,
+                "Should be exactly one OpenTelemetry LoggingHandler",
+            )
+            logging.config.dictConfig(
+                {
+                    "version": 1,
+                    "handlers": {
+                        "default": {
+                            "level": "INFO",
+                            "class": "logging.StreamHandler",
+                            "stream": "ext://sys.stdout",
+                        },
+                    },
+                    "loggers": {
+                        "": {  # root logger
+                            "handlers": ["default"],
+                            "level": "WARNING",
+                            "propagate": False,
+                        },
+                    },
+                }
+            )
+            print(root.handlers)
+            self.assertEqual(len(root.handlers), 2)
+
+            logging_handlers = [
+                h for h in root.handlers if isinstance(h, LoggingHandler)
+            ]
+            self.assertEqual(
+                len(logging_handlers),
+                1,
+                "Should still have exactly one OpenTelemetry LoggingHandler",
+            )
+
 
 class TestMetricsInit(TestCase):
     def setUp(self):
@@ -1169,3 +1215,11 @@ def test_preserves_handlers(self):
             self.assertIs(h1, h2)
 
         root_logger.removeHandler(test_handler)
+
+
+pytest.main(
+    [
+        "-x",
+        "/usr/local/google/home/dylanrussell/archivist_backup_250529_133018/reinstate/opentelemetry-python/opentelemetry-sdk/tests/test_configurator.py",
+    ]
+)

From fc78d8e43c3191672b5c7593b9815871c03f7895 Mon Sep 17 00:00:00 2001
From: Dylan Russell <dylanrus@gmail.com>
Date: Thu, 26 Jun 2025 16:03:09 +0000
Subject: [PATCH 03/13] Some change

---
 .../sdk/_configuration/__init__.py            |   1 +
 opentelemetry-sdk/tests/test_configurator.py  | 126 ++++++++++--------
 2 files changed, 72 insertions(+), 55 deletions(-)

diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
index 85080284273..415e1a3a3b2 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
@@ -274,6 +274,7 @@ def overwritten_config_fn(*args, **kwargs):
             config_fn(*args, **kwargs)
             if handler not in root.handlers:
                 root.addHandler(handler)
+
         return overwritten_config_fn
 
     logging.config.fileConfig = wrapper(logging.config.fileConfig)
diff --git a/opentelemetry-sdk/tests/test_configurator.py b/opentelemetry-sdk/tests/test_configurator.py
index c13123828fc..50528ef06fa 100644
--- a/opentelemetry-sdk/tests/test_configurator.py
+++ b/opentelemetry-sdk/tests/test_configurator.py
@@ -23,7 +23,6 @@
 from unittest import TestCase, mock
 from unittest.mock import Mock, patch
 
-import pytest
 from pytest import raises
 
 from opentelemetry import trace
@@ -626,48 +625,50 @@ def tearDown(self):
         ]
 
     def test_logging_init_empty(self):
-        auto_resource = Resource.create(
-            {
-                "telemetry.auto.version": "auto-version",
-            }
-        )
-        _init_logging({}, resource=auto_resource)
-        self.assertEqual(self.set_provider_mock.call_count, 1)
-        provider = self.set_provider_mock.call_args[0][0]
-        self.assertIsInstance(provider, DummyLoggerProvider)
-        self.assertIsInstance(provider.resource, Resource)
-        self.assertEqual(
-            provider.resource.attributes.get("telemetry.auto.version"),
-            "auto-version",
-        )
-        self.event_logger_provider_mock.assert_called_once_with(
-            logger_provider=provider
-        )
-        self.set_event_logger_provider_mock.assert_called_once_with(
-            self.event_logger_provider_instance_mock
-        )
+        with ResetGlobalLoggingState():
+            auto_resource = Resource.create(
+                {
+                    "telemetry.auto.version": "auto-version",
+                }
+            )
+            _init_logging({}, resource=auto_resource)
+            self.assertEqual(self.set_provider_mock.call_count, 1)
+            provider = self.set_provider_mock.call_args[0][0]
+            self.assertIsInstance(provider, DummyLoggerProvider)
+            self.assertIsInstance(provider.resource, Resource)
+            self.assertEqual(
+                provider.resource.attributes.get("telemetry.auto.version"),
+                "auto-version",
+            )
+            self.event_logger_provider_mock.assert_called_once_with(
+                logger_provider=provider
+            )
+            self.set_event_logger_provider_mock.assert_called_once_with(
+                self.event_logger_provider_instance_mock
+            )
 
     @patch.dict(
         environ,
         {"OTEL_RESOURCE_ATTRIBUTES": "service.name=otlp-service"},
     )
     def test_logging_init_exporter(self):
-        resource = Resource.create({})
-        _init_logging({"otlp": DummyOTLPLogExporter}, resource=resource)
-        self.assertEqual(self.set_provider_mock.call_count, 1)
-        provider = self.set_provider_mock.call_args[0][0]
-        self.assertIsInstance(provider, DummyLoggerProvider)
-        self.assertIsInstance(provider.resource, Resource)
-        self.assertEqual(
-            provider.resource.attributes.get("service.name"),
-            "otlp-service",
-        )
-        self.assertIsInstance(provider.processor, DummyLogRecordProcessor)
-        self.assertIsInstance(
-            provider.processor.exporter, DummyOTLPLogExporter
-        )
-        getLogger(__name__).error("hello")
-        self.assertTrue(provider.processor.exporter.export_called)
+        with ResetGlobalLoggingState():
+            resource = Resource.create({})
+            _init_logging({"otlp": DummyOTLPLogExporter}, resource=resource)
+            self.assertEqual(self.set_provider_mock.call_count, 1)
+            provider = self.set_provider_mock.call_args[0][0]
+            self.assertIsInstance(provider, DummyLoggerProvider)
+            self.assertIsInstance(provider.resource, Resource)
+            self.assertEqual(
+                provider.resource.attributes.get("service.name"),
+                "otlp-service",
+            )
+            self.assertIsInstance(provider.processor, DummyLogRecordProcessor)
+            self.assertIsInstance(
+                provider.processor.exporter, DummyOTLPLogExporter
+            )
+            getLogger(__name__).error("hello")
+            self.assertTrue(provider.processor.exporter.export_called)
 
     @patch.dict(
         environ,
@@ -846,7 +847,7 @@ def test_initialize_components_kwargs(
         )
 
     def test_basicConfig_works_with_otel_handler(self):
-        with ClearLoggingHandlers():
+        with ResetGlobalLoggingState():
             _init_logging(
                 {"otlp": DummyOTLPLogExporter},
                 Resource.create({}),
@@ -868,7 +869,7 @@ def test_basicConfig_works_with_otel_handler(self):
             )
 
     def test_basicConfig_preserves_otel_handler(self):
-        with ClearLoggingHandlers():
+        with ResetGlobalLoggingState():
             _init_logging(
                 {"otlp": DummyOTLPLogExporter},
                 Resource.create({}),
@@ -899,7 +900,7 @@ def test_basicConfig_preserves_otel_handler(self):
             )
 
     def test_dictConfig_preserves_otel_handler(self):
-        with ClearLoggingHandlers():
+        with ResetGlobalLoggingState():
             _init_logging(
                 {"otlp": DummyOTLPLogExporter},
                 Resource.create({}),
@@ -916,22 +917,20 @@ def test_dictConfig_preserves_otel_handler(self):
                 {
                     "version": 1,
                     "handlers": {
-                        "default": {
-                            "level": "INFO",
+                        "console": {
                             "class": "logging.StreamHandler",
+                            "level": "DEBUG",
+                            "formatter": "simple",
                             "stream": "ext://sys.stdout",
                         },
                     },
                     "loggers": {
                         "": {  # root logger
-                            "handlers": ["default"],
-                            "level": "WARNING",
-                            "propagate": False,
+                            "handlers": ["console"],
                         },
                     },
                 }
             )
-            print(root.handlers)
             self.assertEqual(len(root.handlers), 2)
 
             logging_handlers = [
@@ -1180,12 +1179,18 @@ def test_custom_configurator(self, mock_init_comp):
         mock_init_comp.assert_called_once_with(**kwargs)
 
 
-class ClearLoggingHandlers:
+class ResetGlobalLoggingState:
     def __init__(self):
+        self.original_basic_config = logging.basicConfig
+        self.original_dict_config = logging.config.dictConfig
+        self.original_file_config = logging.config.fileConfig
         self.root_logger = getLogger()
         self.original_handlers = None
 
     def __enter__(self):
+        print(self.root_logger.handlers)
+        print(self.root_logger.filters)
+        print(self.root_logger.level)
         self.original_handlers = self.root_logger.handlers[:]
         self.root_logger.handlers = []
         return self
@@ -1194,6 +1199,13 @@ def __exit__(self, exc_type, exc_val, exc_tb):
         self.root_logger.handlers = []
         for handler in self.original_handlers:
             self.root_logger.addHandler(handler)
+        logging.basicConfig = self.original_basic_config
+        logging.config.dictConfig = self.original_dict_config
+        logging.config.fileConfig = self.original_file_config
+        root = getLogger()
+        print(root.handlers)
+        print(root.filters)
+        print(root.level)
 
 
 class TestClearLoggingHandlers(TestCase):
@@ -1205,7 +1217,7 @@ def test_preserves_handlers(self):
         root_logger.addHandler(test_handler)
         expected_handlers = initial_handlers + [test_handler]
 
-        with ClearLoggingHandlers():
+        with ResetGlobalLoggingState():
             self.assertEqual(len(root_logger.handlers), 0)
             temp_handler = logging.StreamHandler()
             root_logger.addHandler(temp_handler)
@@ -1216,10 +1228,14 @@ def test_preserves_handlers(self):
 
         root_logger.removeHandler(test_handler)
 
-
-pytest.main(
-    [
-        "-x",
-        "/usr/local/google/home/dylanrussell/archivist_backup_250529_133018/reinstate/opentelemetry-python/opentelemetry-sdk/tests/test_configurator.py",
-    ]
-)
+    def test_preserves_original_logging_fns(self):
+        def f(x):
+            print("f")
+
+        with ResetGlobalLoggingState():
+            logging.basicConfig = lambda x: print("lambda")
+            logging.config.dictConfig = f
+            logging.config.fileConfig = f
+        self.assertEqual(logging.config.dictConfig.__name__, "dictConfig")
+        self.assertEqual(logging.basicConfig.__name__, "basicConfig")
+        self.assertEqual(logging.config.fileConfig.__name__, "fileConfig")

From 1bbe3f1b8ed52e00eed25013f31c67f09a2aaf21 Mon Sep 17 00:00:00 2001
From: Dylan Russell <dylanrus@gmail.com>
Date: Thu, 26 Jun 2025 17:30:46 +0000
Subject: [PATCH 04/13] Run precommit

---
 opentelemetry-sdk/tests/test_configurator.py | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/opentelemetry-sdk/tests/test_configurator.py b/opentelemetry-sdk/tests/test_configurator.py
index 50528ef06fa..acc0d922489 100644
--- a/opentelemetry-sdk/tests/test_configurator.py
+++ b/opentelemetry-sdk/tests/test_configurator.py
@@ -916,11 +916,11 @@ def test_dictConfig_preserves_otel_handler(self):
             logging.config.dictConfig(
                 {
                     "version": 1,
+                    "disable_existing_loggers": False,  # If this is True all loggers are disabled. Many unit tests assert loggers emit logs.
                     "handlers": {
                         "console": {
                             "class": "logging.StreamHandler",
                             "level": "DEBUG",
-                            "formatter": "simple",
                             "stream": "ext://sys.stdout",
                         },
                     },
@@ -1188,9 +1188,6 @@ def __init__(self):
         self.original_handlers = None
 
     def __enter__(self):
-        print(self.root_logger.handlers)
-        print(self.root_logger.filters)
-        print(self.root_logger.level)
         self.original_handlers = self.root_logger.handlers[:]
         self.root_logger.handlers = []
         return self
@@ -1202,10 +1199,6 @@ def __exit__(self, exc_type, exc_val, exc_tb):
         logging.basicConfig = self.original_basic_config
         logging.config.dictConfig = self.original_dict_config
         logging.config.fileConfig = self.original_file_config
-        root = getLogger()
-        print(root.handlers)
-        print(root.filters)
-        print(root.level)
 
 
 class TestClearLoggingHandlers(TestCase):

From de3f40face57bc9431253f60c64a314763fb7641 Mon Sep 17 00:00:00 2001
From: Dylan Russell <dylanrus@gmail.com>
Date: Thu, 26 Jun 2025 18:38:53 +0000
Subject: [PATCH 05/13] change emit to on_emit

---
 opentelemetry-sdk/tests/logs/test_handler.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/opentelemetry-sdk/tests/logs/test_handler.py b/opentelemetry-sdk/tests/logs/test_handler.py
index 8e46c903539..ec0c8399b2b 100644
--- a/opentelemetry-sdk/tests/logs/test_handler.py
+++ b/opentelemetry-sdk/tests/logs/test_handler.py
@@ -64,7 +64,7 @@ def test_handler_custom_log_level(self):
 
     def test_handler_calling_flush_does_not_cause_deadlock(self):
         class LogProcessorThatAccessesLockOnFlush(LogRecordProcessor):
-            def emit(self, log_data: LogData):
+            def on_emit(self, log_data: LogData):
                 pass
 
             def shutdown(self):

From c6d4089c95ae05394f73330f001c0af624ef9c51 Mon Sep 17 00:00:00 2001
From: Dylan Russell <dylanrus@gmail.com>
Date: Thu, 26 Jun 2025 18:48:12 +0000
Subject: [PATCH 06/13] Fix lint issues

---
 opentelemetry-sdk/tests/logs/test_handler.py | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/opentelemetry-sdk/tests/logs/test_handler.py b/opentelemetry-sdk/tests/logs/test_handler.py
index ec0c8399b2b..9479851e0c8 100644
--- a/opentelemetry-sdk/tests/logs/test_handler.py
+++ b/opentelemetry-sdk/tests/logs/test_handler.py
@@ -62,7 +62,7 @@ def test_handler_custom_log_level(self):
             logger.critical("No Time For Caution")
         self.assertEqual(processor.emit_count(), 2)
 
-    def test_handler_calling_flush_does_not_cause_deadlock(self):
+    def test_handler_calling_flush_does_not_cause_deadlock(self):  # pylint: disable=no-self-use
         class LogProcessorThatAccessesLockOnFlush(LogRecordProcessor):
             def on_emit(self, log_data: LogData):
                 pass
@@ -74,9 +74,8 @@ def force_flush(self, timeout_millis: int = 30000):
                 # Deadlock will happen here IF `flush` starts a new thread
                 # and then blocks, if it just starts a thread and then returns
                 # we don't seem to encounter the issue..
-                logging._lock.acquire()
-                # assert logging._lock.acquire(False) is True
-                logging._lock.release()
+                with logging._lock:  # pylint: disable=protected-access
+                    pass
 
         logger_provider = LoggerProvider()
         processor = LogProcessorThatAccessesLockOnFlush()
@@ -86,7 +85,7 @@ def force_flush(self, timeout_millis: int = 30000):
         # The below code is essentially recreating what is causing the problem inside
         # logging.config.dictConfig. Actually calling logging.config.dictConfig will modify
         # global state inside the logging module and break lots of tests.
-        with logging._lock:
+        with logging._lock:  # pylint: disable=protected-access
             for handler in logging.getLogger().handlers:
                 handler.flush()
 

From 6c9d23151b1d8005148d9f333ca8b32f9fb69f89 Mon Sep 17 00:00:00 2001
From: Dylan Russell <dylanrus@gmail.com>
Date: Thu, 26 Jun 2025 18:52:10 +0000
Subject: [PATCH 07/13] Add changelog

---
 CHANGELOG.md | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index ba135db4f87..cf8c914e292 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+- Overwrite logging.config.fileConfig and logging.config.dictConfig to ensure
+the OTLP `LogHandler` remains attached to the root logger. Fix a bug that
+can cause a deadlock to occur over `logging._lock` in some cases ([#4636](https://github.com/open-telemetry/opentelemetry-python/pull/4636)).
 - Update OTLP proto to v1.7 [#4645](https://github.com/open-telemetry/opentelemetry-python/pull/4645).
 - Add `event_name` as a top level field in the `LogRecord`. Events are now simply logs with the
 `event_name` field set, the logs SDK should be used to emit events ([#4652](https://github.com/open-telemetry/opentelemetry-python/pull/4652)).

From 3f7c4fd42eef414b5ef62f235c86af6d6b3bc6c2 Mon Sep 17 00:00:00 2001
From: Dylan Russell <dylanrus@gmail.com>
Date: Wed, 9 Jul 2025 15:03:50 +0000
Subject: [PATCH 08/13] Get rid of test that may deadlock and flushOnClose
 approach

---
 .../tests/logs/test_log_record.py             |  4 +++
 .../sdk/_logs/_internal/__init__.py           |  1 -
 opentelemetry-sdk/tests/logs/test_handler.py  | 27 -------------------
 3 files changed, 4 insertions(+), 28 deletions(-)

diff --git a/opentelemetry-api/tests/logs/test_log_record.py b/opentelemetry-api/tests/logs/test_log_record.py
index a06ed8dabfc..200d61b63d2 100644
--- a/opentelemetry-api/tests/logs/test_log_record.py
+++ b/opentelemetry-api/tests/logs/test_log_record.py
@@ -25,3 +25,7 @@ class TestLogRecord(unittest.TestCase):
     def test_log_record_observed_timestamp_default(self, time_ns_mock):  # type: ignore
         time_ns_mock.return_value = OBSERVED_TIMESTAMP
         self.assertEqual(LogRecord().observed_timestamp, OBSERVED_TIMESTAMP)
+    
+    def test_context_used_by_default(self):
+        record = LogRecord()
+        
diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py
index 9a3d3b3b5fd..c617129dc08 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py
@@ -551,7 +551,6 @@ def __init__(
     ) -> None:
         super().__init__(level=level)
         self._logger_provider = logger_provider or get_logger_provider()
-        # self.flushOnClose = False
 
     @staticmethod
     def _get_attributes(record: logging.LogRecord) -> _ExtendedAttributes:
diff --git a/opentelemetry-sdk/tests/logs/test_handler.py b/opentelemetry-sdk/tests/logs/test_handler.py
index 9479851e0c8..55526dc2b6a 100644
--- a/opentelemetry-sdk/tests/logs/test_handler.py
+++ b/opentelemetry-sdk/tests/logs/test_handler.py
@@ -62,33 +62,6 @@ def test_handler_custom_log_level(self):
             logger.critical("No Time For Caution")
         self.assertEqual(processor.emit_count(), 2)
 
-    def test_handler_calling_flush_does_not_cause_deadlock(self):  # pylint: disable=no-self-use
-        class LogProcessorThatAccessesLockOnFlush(LogRecordProcessor):
-            def on_emit(self, log_data: LogData):
-                pass
-
-            def shutdown(self):
-                pass
-
-            def force_flush(self, timeout_millis: int = 30000):
-                # Deadlock will happen here IF `flush` starts a new thread
-                # and then blocks, if it just starts a thread and then returns
-                # we don't seem to encounter the issue..
-                with logging._lock:  # pylint: disable=protected-access
-                    pass
-
-        logger_provider = LoggerProvider()
-        processor = LogProcessorThatAccessesLockOnFlush()
-        logger_provider.add_log_record_processor(processor)
-        handler = LoggingHandler(logger_provider=logger_provider)
-        logging.getLogger().addHandler(handler)
-        # The below code is essentially recreating what is causing the problem inside
-        # logging.config.dictConfig. Actually calling logging.config.dictConfig will modify
-        # global state inside the logging module and break lots of tests.
-        with logging._lock:  # pylint: disable=protected-access
-            for handler in logging.getLogger().handlers:
-                handler.flush()
-
     # pylint: disable=protected-access
     def test_log_record_emit_noop(self):
         noop_logger_provder = NoOpLoggerProvider()

From 9b45309193aa4e228d8ebefc5327ae061982f81c Mon Sep 17 00:00:00 2001
From: Dylan Russell <dylanrus@gmail.com>
Date: Wed, 9 Jul 2025 15:07:53 +0000
Subject: [PATCH 09/13] Run precommit

---
 opentelemetry-api/tests/logs/test_log_record.py | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/opentelemetry-api/tests/logs/test_log_record.py b/opentelemetry-api/tests/logs/test_log_record.py
index 200d61b63d2..a06ed8dabfc 100644
--- a/opentelemetry-api/tests/logs/test_log_record.py
+++ b/opentelemetry-api/tests/logs/test_log_record.py
@@ -25,7 +25,3 @@ class TestLogRecord(unittest.TestCase):
     def test_log_record_observed_timestamp_default(self, time_ns_mock):  # type: ignore
         time_ns_mock.return_value = OBSERVED_TIMESTAMP
         self.assertEqual(LogRecord().observed_timestamp, OBSERVED_TIMESTAMP)
-    
-    def test_context_used_by_default(self):
-        record = LogRecord()
-        

From 6645b73456eb1205ac026b3fcfc195b5aa145eb5 Mon Sep 17 00:00:00 2001
From: Dylan Russell <dylanrus@gmail.com>
Date: Mon, 14 Jul 2025 17:14:29 +0000
Subject: [PATCH 10/13] Respond to comments on PR

---
 .../opentelemetry/sdk/_configuration/__init__.py   | 14 ++++++++------
 .../opentelemetry/sdk/_logs/_internal/__init__.py  |  2 ++
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
index 415e1a3a3b2..f3f31de3080 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
@@ -267,13 +267,15 @@ def _overwrite_logging_config_fns(handler):
 
     def wrapper(config_fn):
         def overwritten_config_fn(*args, **kwargs):
-            # This is needed for basicConfig only. basicConfig when called by
-            # the user's program will be a no-op if the root handler was configured.
-            if len(root.handlers) == 1 and root.handlers[0] == handler:
-                root.handlers.pop()
+            removedHandler = False
+            # We don't want the OTLP handler to be modified or deleted by the logging config functions.
+            # So we remove it and then add it back after the function call.
+            if handler in root.handlers:
+                removedHandler = True
+                root.handlers.remove(handler)
             config_fn(*args, **kwargs)
-            if handler not in root.handlers:
-                root.addHandler(handler)
+            if removedHandler:
+                root.addHandler(handler)                
 
         return overwritten_config_fn
 
diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py
index c617129dc08..d5856077338 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py
@@ -643,6 +643,8 @@ def flush(self) -> None:
         if hasattr(self._logger_provider, "force_flush") and callable(
             self._logger_provider.force_flush
         ):
+            # This is done in a separate thread to avoid a potential deadlock, for
+            # details see https://github.com/open-telemetry/opentelemetry-python/pull/4636.
             thread = threading.Thread(target=self._logger_provider.force_flush)
             thread.start()
 

From 602c2dcbb10487f5f7a76f3fd0b933749cb23d37 Mon Sep 17 00:00:00 2001
From: Dylan Russell <dylanrus@gmail.com>
Date: Wed, 16 Jul 2025 21:08:45 +0000
Subject: [PATCH 11/13] Respond to review comments..

---
 .../opentelemetry/sdk/_configuration/__init__.py | 16 +++++++++-------
 opentelemetry-sdk/tests/test_configurator.py     |  2 +-
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
index f3f31de3080..42f30a49e44 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
@@ -262,20 +262,22 @@ def _init_logging(
         _overwrite_logging_config_fns(handler)
 
 
-def _overwrite_logging_config_fns(handler):
+def _overwrite_logging_config_fns(handler: LoggingHandler) -> None:
     root = logging.getLogger()
 
-    def wrapper(config_fn):
+    def wrapper(config_fn: Callable) -> Callable:
         def overwritten_config_fn(*args, **kwargs):
-            removedHandler = False
+            removed_handler = False
             # We don't want the OTLP handler to be modified or deleted by the logging config functions.
             # So we remove it and then add it back after the function call.
             if handler in root.handlers:
-                removedHandler = True
+                removed_handler = True
                 root.handlers.remove(handler)
-            config_fn(*args, **kwargs)
-            if removedHandler:
-                root.addHandler(handler)                
+            try:
+                config_fn(*args, **kwargs)
+            finally:
+                if removed_handler:
+                    root.addHandler(handler)
 
         return overwritten_config_fn
 
diff --git a/opentelemetry-sdk/tests/test_configurator.py b/opentelemetry-sdk/tests/test_configurator.py
index acc0d922489..37ec2fa85f9 100644
--- a/opentelemetry-sdk/tests/test_configurator.py
+++ b/opentelemetry-sdk/tests/test_configurator.py
@@ -1226,7 +1226,7 @@ def f(x):
             print("f")
 
         with ResetGlobalLoggingState():
-            logging.basicConfig = lambda x: print("lambda")
+            logging.basicConfig = f
             logging.config.dictConfig = f
             logging.config.fileConfig = f
         self.assertEqual(logging.config.dictConfig.__name__, "dictConfig")

From c8bdc113dfde9efe8f48283a3fc588bf1758e983 Mon Sep 17 00:00:00 2001
From: Dylan Russell <dylanrus@gmail.com>
Date: Thu, 17 Jul 2025 13:41:24 +0000
Subject: [PATCH 12/13] Add comment

---
 .../src/opentelemetry/sdk/_configuration/__init__.py             | 1 +
 1 file changed, 1 insertion(+)

diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
index 42f30a49e44..43aa7c9649e 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/_configuration/__init__.py
@@ -276,6 +276,7 @@ def overwritten_config_fn(*args, **kwargs):
             try:
                 config_fn(*args, **kwargs)
             finally:
+                # Ensure handler is added back if logging function throws exception.
                 if removed_handler:
                     root.addHandler(handler)
 

From b5e344df675344fffcb085e1f3a38d10be83c3a1 Mon Sep 17 00:00:00 2001
From: Dylan Russell <dylanrus@gmail.com>
Date: Thu, 17 Jul 2025 13:56:29 +0000
Subject: [PATCH 13/13] Fix tests, add comment

---
 opentelemetry-sdk/tests/test_configurator.py | 28 +++++++++++---------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/opentelemetry-sdk/tests/test_configurator.py b/opentelemetry-sdk/tests/test_configurator.py
index eb0897dcf66..6e9221b124d 100644
--- a/opentelemetry-sdk/tests/test_configurator.py
+++ b/opentelemetry-sdk/tests/test_configurator.py
@@ -688,18 +688,19 @@ def test_logging_init_exporter(self):
             self.assertTrue(provider.processor.exporter.export_called)
 
     def test_logging_init_exporter_uses_exporter_args_map(self):
-        resource = Resource.create({})
-        _init_logging(
-            {"otlp": DummyOTLPLogExporter},
-            resource=resource,
-            exporter_args_map={
-                DummyOTLPLogExporter: {"compression": "gzip"},
-                DummyOTLPMetricExporter: {"compression": "no"},
-            },
-        )
-        self.assertEqual(self.set_provider_mock.call_count, 1)
-        provider = self.set_provider_mock.call_args[0][0]
-        self.assertEqual(provider.processor.exporter.compression, "gzip")
+        with ResetGlobalLoggingState():
+            resource = Resource.create({})
+            _init_logging(
+                {"otlp": DummyOTLPLogExporter},
+                resource=resource,
+                exporter_args_map={
+                    DummyOTLPLogExporter: {"compression": "gzip"},
+                    DummyOTLPMetricExporter: {"compression": "no"},
+                },
+            )
+            self.assertEqual(self.set_provider_mock.call_count, 1)
+            provider = self.set_provider_mock.call_args[0][0]
+            self.assertEqual(provider.processor.exporter.compression, "gzip")
 
     @patch.dict(
         environ,
@@ -1232,6 +1233,9 @@ def test_custom_configurator(self, mock_init_comp):
         mock_init_comp.assert_called_once_with(**kwargs)
 
 
+# Any test that calls _init_logging with setup_logging_handler=True
+# should call _init_logging within this context manager, to
+# ensure the global logging state is reset after the test.
 class ResetGlobalLoggingState:
     def __init__(self):
         self.original_basic_config = logging.basicConfig