From 18d21df367bf9ab5554635f5c6d107f2cf2206a5 Mon Sep 17 00:00:00 2001
From: Fabian von Feilitzsch <fabian@fabianism.us>
Date: Thu, 6 Feb 2020 12:05:23 -0500
Subject: [PATCH 1/2] Cleanup ThreadPool with atexit rather than __del__

This removes the __del__ function from the generated Python client,
and replaces it with a cleanup function. When a ThreadPool is created,
the cleanup function is registered with the atexit module.

This PR also allows the client to be used as a context manager, which
will automatically clean up after itself rather than having to wait til
process exit.

This fixes issue #1037, where the API client could hang indefinitely at
garbage collection.
---
 kubernetes/client/api_client.py | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/kubernetes/client/api_client.py b/kubernetes/client/api_client.py
index 498517651e..fde1a17f48 100644
--- a/kubernetes/client/api_client.py
+++ b/kubernetes/client/api_client.py
@@ -10,6 +10,7 @@
 
 from __future__ import absolute_import
 
+import atexit
 import datetime
 import json
 import mimetypes
@@ -77,11 +78,19 @@ def __init__(self, configuration=None, header_name=None, header_value=None,
         # Set default User-Agent.
         self.user_agent = 'OpenAPI-Generator/11.0.0-snapshot/python'
 
-    def __del__(self):
+    def __enter__(self):
+        return self
+
+    def __exit__(self, exc_type, exc_value, traceback):
+        self.close()
+
+    def close(self):
         if self._pool:
             self._pool.close()
             self._pool.join()
             self._pool = None
+            if hasattr(atexit, 'unregister'):
+                atexit.unregister(self.close)
 
     @property
     def pool(self):
@@ -89,6 +98,7 @@ def pool(self):
          avoids instantiating unused threadpool for blocking clients.
         """
         if self._pool is None:
+            atexit.register(self.close)
             self._pool = ThreadPool(self.pool_threads)
         return self._pool
 

From 13dffb897617f87aaaee247095107d7011e002d5 Mon Sep 17 00:00:00 2001
From: Fabian von Feilitzsch <fabian@fabianism.us>
Date: Thu, 6 Feb 2020 12:37:16 -0500
Subject: [PATCH 2/2] Add test to ensure kubernetes client threadpool is
 cleaned up

---
 kubernetes/test/test_api_client.py | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)
 create mode 100644 kubernetes/test/test_api_client.py

diff --git a/kubernetes/test/test_api_client.py b/kubernetes/test/test_api_client.py
new file mode 100644
index 0000000000..f0a9416cf7
--- /dev/null
+++ b/kubernetes/test/test_api_client.py
@@ -0,0 +1,25 @@
+# coding: utf-8
+
+
+import atexit
+import weakref
+import unittest
+
+import kubernetes
+
+
+class TestApiClient(unittest.TestCase):
+
+    def test_context_manager_closes_threadpool(self):
+        with kubernetes.client.ApiClient() as client:
+            self.assertIsNotNone(client.pool)
+            pool_ref = weakref.ref(client._pool)
+            self.assertIsNotNone(pool_ref())
+        self.assertIsNone(pool_ref())
+
+    def test_atexit_closes_threadpool(self):
+        client = kubernetes.client.ApiClient()
+        self.assertIsNotNone(client.pool)
+        self.assertIsNotNone(client._pool)
+        atexit._run_exitfuncs()
+        self.assertIsNone(client._pool)