🐛 Fix OverwhelmedTraffic error with conn that receive GoAway event af…

…ter an idle period

CHANGES.rst

@@ -1,7 +1,10 @@
-2.12.902 (2024-12-05)
+2.12.902 (2024-12-06)
 =====================
 
 - Fixed a rare issue where Happy-Eyeballs algorithm would not respect timeout for a plain HTTP connection where all available endpoints are unreachable.
+- Fixed an issue where a HTTP/2 idle connection would be considered "used/saturated" instead of "idle" when remote expressed wish to goaway.
+  This issue can lead to a ``traffic_police.OverwhelmedTraffic`` in synchronous context and indefinite hang in asynchronous after awhile.
+- Increased default keepalive window to 1h by default for HTTP/2, and HTTP/3.
 
 2.12.901 (2024-12-04)
 =====================

src/urllib3/_constant.py

@@ -247,6 +247,6 @@ def __new__(
 DEFAULT_BACKGROUND_WATCH_WINDOW: float = 5.0
 MINIMAL_BACKGROUND_WATCH_WINDOW: float = 0.05
 
-DEFAULT_KEEPALIVE_DELAY: float = 300.0
+DEFAULT_KEEPALIVE_DELAY: float = 3600.0
 DEFAULT_KEEPALIVE_IDLE_WINDOW: float = 60.0
 MINIMAL_KEEPALIVE_IDLE_WINDOW: float = 1.0

src/urllib3/backend/hface.py

@@ -152,7 +152,11 @@ def __init__(
     def is_saturated(self) -> bool:
         if self._protocol is None:
             return True
-        return self._protocol.is_available() is False
+        # is_available also includes whether we must goaway
+        # we want to focus on stream capacity here.
+        if self._protocol.is_available() is False:
+            return self._protocol.has_expired() is False
+        return False
 
     @property
     def is_multiplexed(self) -> bool:

src/urllib3/connection.py

@@ -290,6 +290,8 @@ def is_closed(self) -> bool:
     def is_connected(self) -> bool:
         if self.sock is None:
             return False
+        # has_expired can be True when the connection isn't dead
+        # with GoAway for example.
         if self._promises or self._pending_responses:
             return True
         return self._protocol is not None and self._protocol.has_expired() is False