The C1 fix from review #007 added keep_alive_interval(15s) +
keep_alive_timeout(60s) on the HTTP/2 builders. However,
keep_alive_timeout is the timeout for receiving a PONG response to a
PING, not an idle timeout. Well-behaved HTTP/2 clients (including
crawlers) respond to PINGs, resetting the timeout indefinitely. After
6 days of uptime, the proxy had 930+ idle connections (some 145 hours
old) that were never reaped.
Fix: add a custom idle timeout that tracks real request activity and
closes connections with no in-flight requests for longer than the
configured timeout, regardless of PING/PONG activity.
- IdleState: per-connection last_activity + in_flight counter
- IdleTrackingService: tower Service wrapper that updates last_activity
and in_flight on call() and on response completion (prevents killing
long-running requests like large git clones)
- idle_watchdog: races against serve_connection in tokio::select!,
fires only when in_flight == 0 and idle_for >= timeout
- HTTP/1.1 path: header_read_timeout already covers between-request
idle (verified in hyper source); watchdog is defense-in-depth
- HTTP/2 path: watchdog is the primary fix (hyper has no native
request-activity-based idle timeout)
Also refactored build_manual_server_config to extract
build_manual_server_config_from_certs for testability (in-memory
certs/keys for integration tests with rcgen).
Tests: 8 unit tests for IdleState/watchdog logic, 2 integration tests
verifying idle connections are closed and active ones are not.
Closes review #008.
glm-5.2
4ab8c516d8