Function _spawn_server

eval/run_compare.py:261–326

Boot a uvicorn server in a subprocess and tear it down on exit. ``server_module`` is e.g. ``scripts.clawcodex_api_server:app`` — passed straight through to uvicorn. ``cwd`` is ``swebench_repo`` so the ``scripts`` package import resolves.

(
    *,
    swebench_repo: Path,
    swebench_python: str,
    server_module: str,
    port: int,
    log_path: Path,
    env: dict[str, str],
)

@contextlib.contextmanager
def _spawn_server(
    *,
    swebench_repo: Path,
    swebench_python: str,
    server_module: str,
    port: int,
    log_path: Path,
    env: dict[str, str],
) -> Iterable[subprocess.Popen[bytes]]:
    """Boot a uvicorn server in a subprocess and tear it down on exit.

    ``server_module`` is e.g. ``scripts.clawcodex_api_server:app`` — passed
    straight through to uvicorn. ``cwd`` is ``swebench_repo`` so the
    ``scripts`` package import resolves.
    """
    cmd = [
        swebench_python,
        "-m",
        "uvicorn",
        server_module,
        "--host",
        "127.0.0.1",
        "--port",
        str(port),
        "--log-level",
        "warning",
    ]
    log_path.parent.mkdir(parents=True, exist_ok=True)
    log_handle = log_path.open("wb")
    _info(f"  starting: {' '.join(cmd)}  (cwd={swebench_repo})")
    # On Windows, place uvicorn in its own process group so CTRL_BREAK_EVENT
    # only reaches uvicorn, not the run_compare process and any sibling harness
    # subprocess we spawn next. Without this, the signal leaks to the whole
    # console group and aborts the next harness run with an empty log.
    popen_kwargs: dict[str, object] = {}
    if os.name == "nt":
        popen_kwargs["creationflags"] = subprocess.CREATE_NEW_PROCESS_GROUP
    proc = subprocess.Popen(  # noqa: S603
        cmd,
        cwd=str(swebench_repo),
        stdout=log_handle,
        stderr=subprocess.STDOUT,
        env=env,
        **popen_kwargs,
    )
    try:
        try:
            _wait_for_health(f"http://127.0.0.1:{port}/health", timeout=30.0)
        except RuntimeError:
            # /health may not exist on older clawcodex_api_server.py — accept
            # any TCP-level liveness instead.
            _info("  /health probe failed; falling back to socket-only liveness check")
            _wait_for_socket("127.0.0.1", port, timeout=30.0)
        yield proc
    finally:
        if proc.poll() is None:
            _info(f"  stopping uvicorn (pid={proc.pid}) on port {port}")
            try: