fix: prevent service crash-loop on port-in-use at startup

serve() now kills any stale process holding the configured port before
uvicorn tries to bind. Prevents the crash-loop where systemd restarts
muxplex but the old process is still holding port 8088 (observed:
2075+ restarts before manual intervention).

New helper _kill_stale_port_holder(port):
- Runs lsof -ti :<port> to find occupying PIDs
- Sends SIGTERM to all foreign PIDs (skips own PID)
- Waits 1 second for the port to free
- Silently swallows all errors (missing lsof, permission denied)
  so a broken environment never prevents startup

Also adds TimeoutStopSec=10 and KillMode=mixed to the systemd unit
template so the old process gets SIGKILL'd if it does not exit on
SIGTERM within 10 seconds — preventing the SIGTERM-ignored zombie
scenario entirely.

This commit is contained in:

Brian Krabach

2026-04-02 00:51:20 -07:00

parent b310b7f8a6

commit 000c71c40d

4 changed files with 204 additions and 0 deletions

									
										muxplex/service.py
									
		+2
		
												View File
												
				@@ -27,6 +27,8 @@ Type=simple

				ExecStart={exec_start}

				Restart=on-failure

				RestartSec=5s

				TimeoutStopSec=10

				KillMode=mixed

				Environment=PATH={safe_path}

				[Install]