Keep the session token out of the HTTP client's debug log (#1835)

Camera logins over `SslAesTransport` send their requests to `/stok=<token>/ds`, and `HttpClient` logs every URL it posts to at debug, so the session token ends up in the debug logs people paste into issues.

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

kasa/httpclient.py

@@ -5,6 +5,7 @@ from __future__ import annotations
 import asyncio
 import builtins
 import logging
+import re
 import ssl
 import time
 from typing import Any
@@ -22,6 +23,9 @@ from .json import loads as json_loads
 
 _LOGGER = logging.getLogger(__name__)
 
+# The session token in /stok=<token>/ds URLs, e.g. after a camera's secure login
+_SESSION_TOKEN = re.compile(r"(stok=)[^/?#]+")
+
 
 def get_cookie_jar() -> aiohttp.CookieJar:
     """Return a new cookie jar with the correct options for device communication."""
@@ -86,7 +90,8 @@ class HttpClient:
                 )
                 await asyncio.sleep(sleep)
 
-        _LOGGER.debug("Posting to %s", url)
+        if _LOGGER.isEnabledFor(logging.DEBUG):
+            _LOGGER.debug("Posting to %s", _SESSION_TOKEN.sub(r"\1REDACTED", str(url)))
         response_data = None
         self._last_url = url
         self.client.cookie_jar.clear()

tests/test_httpclient.py

@@ -1,4 +1,5 @@
 import builtins
+import logging
 import re
 
 import aiohttp
@@ -114,3 +115,37 @@ async def test_httpclient_errors(
         assert mock_response.call_count == 1
     else:
         assert conn.call_count == 1
+
+
+class _OkResponse:
+    status = 200
+    connection = None
+
+    async def __aenter__(self):
+        return self
+
+    async def __aexit__(self, exc_t, exc_v, exc_tb) -> None:
+        pass
+
+    async def read(self) -> bytes:
+        return b"{}"
+
+
+async def test_httpclient_debug_log_hides_session_token(
+    mocker: MockerFixture, caplog: pytest.LogCaptureFixture
+) -> None:
+    """The /stok=<token>/ds session token of a camera login is not logged."""
+
+    async def _post(url, *_, **__):
+        return _OkResponse()
+
+    mocker.patch.object(aiohttp.ClientSession, "post", side_effect=_post)
+    client = HttpClient(DeviceConfig("127.0.0.1"))
+
+    with caplog.at_level(logging.DEBUG, logger="kasa.httpclient"):
+        await client.post(URL("https://127.0.0.1/stok=S3cr3tT0k3n/ds"), data=b"x")
+        await client.post(URL("http://127.0.0.1/app/handshake1"), data=b"x")
+
+    assert "S3cr3tT0k3n" not in caplog.text
+    assert "Posting to https://127.0.0.1/stok=REDACTED/ds" in caplog.text
+    assert "Posting to http://127.0.0.1/app/handshake1" in caplog.text