From 59f4bfdd4b610426441a065c282ff11f5c480679 Mon Sep 17 00:00:00 2001
From: Kubernetes Prow Robot <k8s-ci-robot@users.noreply.github.com>
Date: Mon, 10 Feb 2020 14:07:54 -0800
Subject: [PATCH] Merge pull request #1073 from fabianvf/fix-py3-hang

Cleanup ThreadPool with atexit rather than __del__

(cherry picked from commit 0976d59d6ff206f2f428cabc7a6b7b1144843b2a)
---
 kubernetes/client/api_client.py    | 14 ++++++++++++--
 kubernetes/test/test_api_client.py | 25 +++++++++++++++++++++++++
 2 files changed, 37 insertions(+), 2 deletions(-)
 create mode 100644 kubernetes/test/test_api_client.py

diff --git a/kubernetes/client/api_client.py b/kubernetes/client/api_client.py
index 40a451cff5..9e60ded5f5 100644
--- a/kubernetes/client/api_client.py
+++ b/kubernetes/client/api_client.py
@@ -14,6 +14,7 @@
 import os
 import re
 import json
+import atexit
 import mimetypes
 import tempfile
 from multiprocessing.pool import ThreadPool
@@ -74,12 +75,20 @@ def __init__(self, configuration=None, header_name=None, header_value=None,
         self.cookie = cookie
         # Set default User-Agent.
         self.user_agent = 'Swagger-Codegen/10.0.1/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):
@@ -87,6 +96,7 @@ 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
 
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)