From 1a3b51b9efab1a04e508dc19c1e036290049c3be Mon Sep 17 00:00:00 2001
From: thev1ndu <itsthw9@gmail.com>
Date: Mon, 31 Aug 2026 12:29:46 +0530
Subject: [PATCH] Add example for enabling TCP keepalive via socket_options

Configuration.socket_options is already wired through to urllib3, but
there is no example showing how to use it. Long-lived watches and log
streams can hang when a connection is silently dropped; TCP keepalive
lets the kernel detect the dead peer. Add an example and list it in the
examples README.

Fixes #2067
---
 examples/README.md        |  1 +
 examples/tcp_keepalive.py | 68 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 69 insertions(+)
 create mode 100644 examples/tcp_keepalive.py

diff --git a/examples/README.md b/examples/README.md
index 43a11fba4e..c6774dda22 100644
--- a/examples/README.md
+++ b/examples/README.md
@@ -9,6 +9,7 @@ comments throughout the code.
 
 - pod_logs.py — basic (blocking) pod log streaming example
 - pod_logs_non_blocking.py — non-blocking streaming of pod logs with graceful shutdown
+- tcp_keepalive.py — enable TCP keepalive via Configuration.socket_options so dead connections on long-lived watches/log streams are detected
 
 ## Setup
 
diff --git a/examples/tcp_keepalive.py b/examples/tcp_keepalive.py
new file mode 100644
index 0000000000..204d83a83f
--- /dev/null
+++ b/examples/tcp_keepalive.py
@@ -0,0 +1,68 @@
+# Copyright 2026 The Kubernetes Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Shows how to enable TCP keepalive on the client connections.
+
+Long-lived requests such as watches or `follow=True` log streams can hang
+silently when the connection is dropped by a load balancer or a firewall
+without a FIN/RST reaching the client. Enabling TCP keepalive lets the
+kernel detect a dead peer and close the socket, so the client raises an
+error instead of blocking forever.
+
+The `socket_options` on `Configuration` are passed straight to the
+underlying urllib3 connection pool, on top of urllib3's own defaults.
+"""
+
+import socket
+
+from kubernetes import client, config
+
+
+def keepalive_socket_options():
+    """Return socket options that enable TCP keepalive.
+
+    TCP_KEEPIDLE / TCP_KEEPINTVL / TCP_KEEPCNT are not available on every
+    platform, so they are added only when the running platform exposes them.
+    """
+    options = [(socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1)]
+
+    # Start probing after 30s idle, probe every 10s, drop after 6 failures.
+    if hasattr(socket, "TCP_KEEPIDLE"):
+        options.append((socket.IPPROTO_TCP, socket.TCP_KEEPIDLE, 30))
+    if hasattr(socket, "TCP_KEEPINTVL"):
+        options.append((socket.IPPROTO_TCP, socket.TCP_KEEPINTVL, 10))
+    if hasattr(socket, "TCP_KEEPCNT"):
+        options.append((socket.IPPROTO_TCP, socket.TCP_KEEPCNT, 6))
+
+    return options
+
+
+def main():
+    config.load_kube_config()
+
+    configuration = client.Configuration.get_default_copy()
+    configuration.socket_options = keepalive_socket_options()
+
+    api_client = client.ApiClient(configuration=configuration)
+    v1 = client.CoreV1Api(api_client=api_client)
+
+    print("Listing pods with TCP keepalive enabled:")
+    ret = v1.list_pod_for_all_namespaces(watch=False)
+    for i in ret.items:
+        print(f"{i.status.pod_ip}\t{i.metadata.namespace}\t{i.metadata.name}")
+
+
+if __name__ == '__main__':
+    main()