Files
nanobot/nanobot/gateway/runtime.py
T

461 lines
15 KiB
Python

"""Background process control for ``nanobot gateway``.
This module intentionally stays small: the CLI owns command wording, while this
runtime owns process state, log files, and platform-specific detach/stop details.
"""
from __future__ import annotations
import ctypes
import json
import os
import signal
import subprocess
import sys
import tempfile
import time
from collections.abc import Callable
from contextlib import suppress
from dataclasses import dataclass
from datetime import UTC, datetime
from pathlib import Path
from typing import Any
from nanobot.config.paths import get_data_dir
@dataclass(frozen=True)
class GatewayStartOptions:
"""Options needed to start a background gateway instance."""
port: int
verbose: bool = False
workspace: str | None = None
config_path: str | None = None
@dataclass(frozen=True)
class GatewayStatus:
"""Current background gateway status."""
running: bool
pid: int | None
state_path: Path
log_path: Path
started_at: str | None = None
port: int | None = None
command: tuple[str, ...] = ()
reason: str = "not_started"
@dataclass(frozen=True)
class RuntimeResult:
"""Result from a gateway runtime control operation."""
ok: bool
message: str
status: GatewayStatus
def build_gateway_command(python_executable: str, options: GatewayStartOptions) -> list[str]:
"""Build a foreground gateway command for process supervisors."""
command = [
python_executable,
"-m",
"nanobot",
"gateway",
"--foreground",
"--port",
str(options.port),
]
if options.verbose:
command.append("--verbose")
if options.workspace:
command.extend(["--workspace", options.workspace])
if options.config_path:
command.extend(["--config", options.config_path])
return command
@dataclass(frozen=True)
class GatewayRuntimePaths:
"""Filesystem layout for one gateway runtime instance."""
run_dir: Path
logs_dir: Path
state_path: Path
log_path: Path
@classmethod
def for_instance(
cls,
*,
data_dir: Path | None = None,
workspace: str | None = None,
config_path: str | None = None,
) -> "GatewayRuntimePaths":
base = data_dir or get_data_dir()
suffix = _instance_suffix(workspace=workspace, config_path=config_path)
run_dir = base / "run"
logs_dir = base / "logs"
stem = "gateway" if suffix is None else f"gateway.{suffix}"
return cls(
run_dir=run_dir,
logs_dir=logs_dir,
state_path=run_dir / f"{stem}.json",
log_path=logs_dir / f"{stem}.log",
)
class GatewayRuntime:
"""Manage a background ``nanobot gateway`` process."""
def __init__(
self,
*,
paths: GatewayRuntimePaths | None = None,
platform_name: str | None = None,
python_executable: str | None = None,
popen: Callable[..., Any] = subprocess.Popen,
subprocess_run: Callable[..., Any] = subprocess.run,
sleep: Callable[[float], None] = time.sleep,
) -> None:
self.paths = paths or GatewayRuntimePaths.for_instance()
self.platform_name = platform_name or _platform_name()
self.python_executable = python_executable or sys.executable
self._popen = popen
self._subprocess_run = subprocess_run
self._sleep = sleep
def start_background(self, options: GatewayStartOptions) -> RuntimeResult:
"""Start gateway as a detached background process."""
current = self.status()
if current.running:
return RuntimeResult(False, "gateway_already_running", current)
command = self._build_child_command(options)
self.paths.run_dir.mkdir(parents=True, exist_ok=True)
self.paths.logs_dir.mkdir(parents=True, exist_ok=True)
with self.paths.log_path.open("a", encoding="utf-8") as log_handle:
process = self._popen(
command,
stdin=subprocess.DEVNULL,
stdout=log_handle,
stderr=subprocess.STDOUT,
**self._popen_platform_kwargs(),
)
pid = int(process.pid)
self._sleep(0.2)
if not self._is_pid_running(pid):
return RuntimeResult(False, "gateway_exited_during_startup", self.status())
identity = self._process_identity(pid)
self._write_state(
{
"pid": pid,
"identity": identity,
"started_at": _utc_now(),
"platform": self.platform_name,
"port": options.port,
"workspace": options.workspace,
"config_path": options.config_path,
"command": command,
"log_path": str(self.paths.log_path),
}
)
return RuntimeResult(True, "gateway_started_background", self.status())
def stop(self, *, timeout_s: int = 20) -> RuntimeResult:
"""Stop the recorded background gateway process."""
status = self.status()
if not status.pid:
return RuntimeResult(False, "gateway_not_running", status)
state = self._read_state()
if not self._record_matches_process(state, status.pid):
self._clear_state()
return RuntimeResult(False, "gateway_state_stale", self.status(reason="stale_state"))
if not self._terminate(status.pid, timeout_s=timeout_s):
return RuntimeResult(False, "gateway_stop_timeout", self.status(reason="stop_timeout"))
self._clear_state()
return RuntimeResult(True, "gateway_stopped", self.status(reason="stopped"))
def restart(self, options: GatewayStartOptions, *, timeout_s: int = 20) -> RuntimeResult:
"""Restart the background gateway."""
stop_result = self.stop(timeout_s=timeout_s)
if not stop_result.ok and stop_result.message not in {"gateway_not_running", "gateway_state_stale"}:
return stop_result
return self.start_background(options)
def status(self, *, reason: str | None = None) -> GatewayStatus:
"""Return live status, clearing stale state when needed."""
state = self._read_state()
pid = _as_int(state.get("pid")) if state else None
if pid is None:
return GatewayStatus(
running=False,
pid=None,
state_path=self.paths.state_path,
log_path=self.paths.log_path,
reason=reason or "not_started",
)
if not self._is_pid_running(pid) or not self._record_matches_process(state, pid):
self._clear_state()
return GatewayStatus(
running=False,
pid=None,
state_path=self.paths.state_path,
log_path=self.paths.log_path,
reason=reason or "stale_state",
)
command = state.get("command")
return GatewayStatus(
running=True,
pid=pid,
state_path=self.paths.state_path,
log_path=self.paths.log_path,
started_at=_as_str(state.get("started_at")),
port=_as_int(state.get("port")),
command=tuple(command) if isinstance(command, list) else (),
reason=reason or "running",
)
def read_log_tail(self, *, tail: int = 200) -> list[str]:
"""Return the last ``tail`` log lines."""
if tail <= 0 or not self.paths.log_path.exists():
return []
try:
lines = self.paths.log_path.read_text(encoding="utf-8", errors="replace").splitlines()
except OSError:
return []
return lines[-tail:]
def follow_logs(self, *, tail: int = 200) -> int:
"""Print existing log tail and follow new log lines."""
for line in self.read_log_tail(tail=tail):
print(line)
self.paths.logs_dir.mkdir(parents=True, exist_ok=True)
self.paths.log_path.touch(exist_ok=True)
try:
with self.paths.log_path.open("r", encoding="utf-8", errors="replace") as handle:
handle.seek(0, os.SEEK_END)
while True:
line = handle.readline()
if line:
print(line.rstrip("\n"))
else:
self._sleep(0.5)
except KeyboardInterrupt:
return 130
def _build_child_command(self, options: GatewayStartOptions) -> list[str]:
return build_gateway_command(self.python_executable, options)
def _popen_platform_kwargs(self) -> dict[str, Any]:
if self.platform_name == "Windows":
flags = 0
flags |= getattr(subprocess, "CREATE_NEW_PROCESS_GROUP", 0)
flags |= getattr(subprocess, "CREATE_NO_WINDOW", 0)
return {"creationflags": flags}
return {"start_new_session": True}
def _terminate(self, pid: int, *, timeout_s: int) -> bool:
if self.platform_name == "Windows":
return self._terminate_windows(pid, timeout_s=timeout_s)
return self._terminate_posix(pid, timeout_s=timeout_s)
def _terminate_posix(self, pid: int, *, timeout_s: int) -> bool:
try:
pgid = os.getpgid(pid)
except OSError:
pgid = None
try:
if pgid is not None:
os.killpg(pgid, signal.SIGTERM)
else:
os.kill(pid, signal.SIGTERM)
except ProcessLookupError:
return True
if self._wait_for_exit(pid, timeout_s):
return True
with suppress(ProcessLookupError):
if pgid is not None:
os.killpg(pgid, signal.SIGKILL)
else:
os.kill(pid, signal.SIGKILL)
return self._wait_for_exit(pid, 2)
def _terminate_windows(self, pid: int, *, timeout_s: int) -> bool:
ctrl_break = getattr(signal, "CTRL_BREAK_EVENT", None)
if ctrl_break is not None:
# Detached Windows children can reject CTRL_BREAK_EVENT with WinError 87;
# keep the existing taskkill fallback for that process shape.
with suppress(ProcessLookupError, OSError):
os.kill(pid, ctrl_break)
if self._wait_for_exit(pid, timeout_s):
return True
self._subprocess_run(
["taskkill", "/PID", str(pid), "/T"],
check=False,
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL,
)
if self._wait_for_exit(pid, 2):
return True
self._subprocess_run(
["taskkill", "/PID", str(pid), "/T", "/F"],
check=False,
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL,
)
return self._wait_for_exit(pid, 2)
def _wait_for_exit(self, pid: int, timeout_s: int | float) -> bool:
deadline = time.monotonic() + max(float(timeout_s), 0.0)
while time.monotonic() < deadline:
if not self._is_pid_running(pid):
return True
self._sleep(0.1)
return not self._is_pid_running(pid)
def _is_pid_running(self, pid: int) -> bool:
if pid <= 0:
return False
if self.platform_name == "Windows":
return _windows_process_identity(pid) is not None
try:
os.kill(pid, 0)
except ProcessLookupError:
return False
except PermissionError:
return True
except OSError:
return False
return True
def _process_identity(self, pid: int) -> str | int | None:
if self.platform_name == "Windows":
return _windows_process_identity(pid)
try:
return os.getpgid(pid)
except OSError:
return None
def _record_matches_process(self, state: dict[str, Any] | None, pid: int) -> bool:
if not state:
return False
recorded = state.get("identity")
if recorded is None:
return True
return recorded == self._process_identity(pid)
def _read_state(self) -> dict[str, Any] | None:
try:
with self.paths.state_path.open(encoding="utf-8") as handle:
payload = json.load(handle)
except (OSError, json.JSONDecodeError, ValueError):
return None
return payload if isinstance(payload, dict) else None
def _write_state(self, payload: dict[str, Any]) -> None:
self.paths.run_dir.mkdir(parents=True, exist_ok=True)
fd, tmp_name = tempfile.mkstemp(
prefix=f"{self.paths.state_path.name}.",
suffix=".tmp",
dir=self.paths.run_dir,
)
tmp_path = Path(tmp_name)
try:
with os.fdopen(fd, "w", encoding="utf-8") as handle:
json.dump(payload, handle, indent=2, ensure_ascii=False)
handle.write("\n")
handle.flush()
os.fsync(handle.fileno())
tmp_path.replace(self.paths.state_path)
finally:
tmp_path.unlink(missing_ok=True)
def _clear_state(self) -> None:
self.paths.state_path.unlink(missing_ok=True)
def _instance_suffix(*, workspace: str | None, config_path: str | None) -> str | None:
raw = "|".join(value for value in (workspace, config_path) if value)
if not raw:
return None
import hashlib
return hashlib.sha1(raw.encode("utf-8")).hexdigest()[:16]
def _platform_name() -> str:
if sys.platform.startswith("win"):
return "Windows"
if sys.platform == "darwin":
return "Darwin"
return "Linux"
def _utc_now() -> str:
return datetime.now(UTC).isoformat().replace("+00:00", "Z")
def _as_int(value: object) -> int | None:
if isinstance(value, int):
return value
if isinstance(value, str):
try:
return int(value)
except ValueError:
return None
return None
def _as_str(value: object) -> str | None:
return value if isinstance(value, str) else None
def _windows_process_identity(pid: int) -> str | None:
if os.name != "nt":
return None
class FileTime(ctypes.Structure):
_fields_ = [("low", ctypes.c_uint32), ("high", ctypes.c_uint32)]
@property
def value(self) -> int:
return (int(self.high) << 32) | int(self.low)
process_query_limited_information = 0x1000
kernel32 = ctypes.windll.kernel32
handle = kernel32.OpenProcess(process_query_limited_information, False, pid)
if not handle:
return None
try:
creation_time = FileTime()
exit_time = FileTime()
kernel_time = FileTime()
user_time = FileTime()
ok = kernel32.GetProcessTimes(
handle,
ctypes.byref(creation_time),
ctypes.byref(exit_time),
ctypes.byref(kernel_time),
ctypes.byref(user_time),
)
if not ok:
return None
exit_code = ctypes.c_uint32()
if not kernel32.GetExitCodeProcess(handle, ctypes.byref(exit_code)):
return None
if exit_code.value != 259:
return None
return str(creation_time.value)
finally:
kernel32.CloseHandle(handle)