hermes-agent/tests/tools/test_browser_orphan_reaper.py
Teknium 304fb921bf
fix: two process leaks (agent-browser daemons, paste.rs sleepers) (#11843)
Both fixes close process leaks observed in production (18+ orphaned
agent-browser node daemons, 15+ orphaned paste.rs sleep interpreters
accumulated over ~3 days, ~2.7 GB RSS).

## agent-browser daemon leak

Previously the orphan reaper (_reap_orphaned_browser_sessions) only ran
from _start_browser_cleanup_thread, which is only invoked on the first
browser tool call in a process. Hermes sessions that never used the
browser never swept orphans, and the cross-process orphan detection
relied on in-process _active_sessions, which doesn't see other hermes
PIDs' sessions (race risk).

- Write <session>.owner_pid alongside the socket dir recording the
  hermes PID that owns the daemon (extracted into _write_owner_pid for
  direct testability).
- Reaper prefers owner_pid liveness over in-process _active_sessions.
  Cross-process safe: concurrent hermes instances won't reap each
  other's daemons. Legacy tracked_names fallback kept for daemons
  that predate owner_pid.
- atexit handler (_emergency_cleanup_all_sessions) now always runs
  the reaper, not just when this process had active sessions —
  every clean hermes exit sweeps accumulated orphans.

## paste.rs auto-delete leak

_schedule_auto_delete spawned a detached Python subprocess per call
that slept 6 hours then issued DELETE requests. No dedup, no tracking —
every 'hermes debug share' invocation added ~20 MB of resident Python
interpreters that stuck around until the sleep finished.

- Replaced the spawn with ~/.hermes/pastes/pending.json: records
  {url, expire_at} entries.
- _sweep_expired_pastes() synchronously DELETEs past-due entries on
  every 'hermes debug' invocation (run_debug() dispatcher).
- Network failures stay in pending.json for up to 24h, then give up
  (paste.rs's own retention handles the 'user never runs hermes again'
  edge case).
- Zero subprocesses; regression test asserts subprocess/Popen/time.sleep
  never appear in the function source (skipping docstrings via AST).

## Validation

|                              | Before        | After        |
|------------------------------|---------------|--------------|
| Orphan agent-browser daemons | 18 accumulated| 2 (live)     |
| paste.rs sleep interpreters  | 15 accumulated| 0            |
| RSS reclaimed                | -             | ~2.7 GB      |
| Targeted tests               | -             | 2253 pass    |

E2E verified: alive-owner daemons NOT reaped; dead-owner daemons
SIGTERM'd and socket dirs cleaned; pending.json sweep deletes expired
entries without spawning subprocesses.
2026-04-17 18:46:30 -07:00

408 lines
15 KiB
Python

"""Tests for _reap_orphaned_browser_sessions() — kills orphaned agent-browser
daemons whose Python parent exited without cleaning up."""
import os
import signal
import textwrap
from pathlib import Path
from unittest.mock import patch, MagicMock
import pytest
@pytest.fixture
def fake_tmpdir(tmp_path):
"""Patch _socket_safe_tmpdir to return a temp dir we control."""
with patch("tools.browser_tool._socket_safe_tmpdir", return_value=str(tmp_path)):
yield tmp_path
@pytest.fixture(autouse=True)
def _isolate_sessions():
"""Ensure _active_sessions is empty for each test."""
import tools.browser_tool as bt
orig = bt._active_sessions.copy()
bt._active_sessions.clear()
yield
bt._active_sessions.clear()
bt._active_sessions.update(orig)
def _make_socket_dir(tmpdir, session_name, pid=None, owner_pid=None):
"""Create a fake agent-browser socket directory with optional PID files.
Args:
tmpdir: base temp directory
session_name: name like "h_abc1234567" or "cdp_abc1234567"
pid: daemon PID to write to <session>.pid (None = no file)
owner_pid: owning hermes PID to write to <session>.owner_pid
(None = no file; tests the legacy path)
"""
d = tmpdir / f"agent-browser-{session_name}"
d.mkdir()
if pid is not None:
(d / f"{session_name}.pid").write_text(str(pid))
if owner_pid is not None:
(d / f"{session_name}.owner_pid").write_text(str(owner_pid))
return d
class TestReapOrphanedBrowserSessions:
"""Tests for the orphan reaper function."""
def test_no_socket_dirs_is_noop(self, fake_tmpdir):
"""No socket dirs => nothing happens, no errors."""
from tools.browser_tool import _reap_orphaned_browser_sessions
_reap_orphaned_browser_sessions() # should not raise
def test_stale_dir_without_pid_file_is_removed(self, fake_tmpdir):
"""Socket dir with no PID file is cleaned up."""
from tools.browser_tool import _reap_orphaned_browser_sessions
d = _make_socket_dir(fake_tmpdir, "h_abc1234567")
assert d.exists()
_reap_orphaned_browser_sessions()
assert not d.exists()
def test_stale_dir_with_dead_pid_is_removed(self, fake_tmpdir):
"""Socket dir whose daemon PID is dead gets cleaned up."""
from tools.browser_tool import _reap_orphaned_browser_sessions
d = _make_socket_dir(fake_tmpdir, "h_dead123456", pid=999999999)
assert d.exists()
_reap_orphaned_browser_sessions()
assert not d.exists()
def test_orphaned_alive_daemon_is_killed(self, fake_tmpdir):
"""Alive daemon not tracked by _active_sessions gets SIGTERM (legacy path).
No owner_pid file => falls back to tracked_names check.
"""
from tools.browser_tool import _reap_orphaned_browser_sessions
d = _make_socket_dir(fake_tmpdir, "h_orphan12345", pid=12345)
kill_calls = []
original_kill = os.kill
def mock_kill(pid, sig):
kill_calls.append((pid, sig))
if sig == 0:
return # pretend process exists
# Don't actually kill anything
with patch("os.kill", side_effect=mock_kill):
_reap_orphaned_browser_sessions()
# Should have checked existence (sig 0) then killed (SIGTERM)
assert (12345, 0) in kill_calls
assert (12345, signal.SIGTERM) in kill_calls
def test_tracked_session_is_not_reaped(self, fake_tmpdir):
"""Sessions tracked in _active_sessions are left alone (legacy path)."""
import tools.browser_tool as bt
from tools.browser_tool import _reap_orphaned_browser_sessions
session_name = "h_tracked1234"
d = _make_socket_dir(fake_tmpdir, session_name, pid=12345)
# Register the session as actively tracked
bt._active_sessions["some_task"] = {"session_name": session_name}
kill_calls = []
def mock_kill(pid, sig):
kill_calls.append((pid, sig))
with patch("os.kill", side_effect=mock_kill):
_reap_orphaned_browser_sessions()
# Should NOT have tried to kill anything
assert len(kill_calls) == 0
# Dir should still exist
assert d.exists()
def test_permission_error_on_kill_check_skips(self, fake_tmpdir):
"""If we can't check the PID (PermissionError), skip it."""
from tools.browser_tool import _reap_orphaned_browser_sessions
d = _make_socket_dir(fake_tmpdir, "h_perm1234567", pid=12345)
def mock_kill(pid, sig):
if sig == 0:
raise PermissionError("not our process")
with patch("os.kill", side_effect=mock_kill):
_reap_orphaned_browser_sessions()
# Dir should still exist (we didn't touch someone else's process)
assert d.exists()
def test_cdp_sessions_are_also_reaped(self, fake_tmpdir):
"""CDP sessions (cdp_ prefix) are also scanned."""
from tools.browser_tool import _reap_orphaned_browser_sessions
d = _make_socket_dir(fake_tmpdir, "cdp_abc1234567")
assert d.exists()
_reap_orphaned_browser_sessions()
# No PID file → cleaned up
assert not d.exists()
def test_non_hermes_dirs_are_ignored(self, fake_tmpdir):
"""Socket dirs that don't match our naming pattern are left alone."""
from tools.browser_tool import _reap_orphaned_browser_sessions
# Create a dir that doesn't match h_* or cdp_* pattern
d = fake_tmpdir / "agent-browser-other_session"
d.mkdir()
(d / "other_session.pid").write_text("12345")
_reap_orphaned_browser_sessions()
# Should NOT be touched
assert d.exists()
def test_corrupt_pid_file_is_cleaned(self, fake_tmpdir):
"""PID file with non-integer content is cleaned up."""
from tools.browser_tool import _reap_orphaned_browser_sessions
d = _make_socket_dir(fake_tmpdir, "h_corrupt1234")
(d / "h_corrupt1234.pid").write_text("not-a-number")
_reap_orphaned_browser_sessions()
assert not d.exists()
class TestOwnerPidCrossProcess:
"""Tests for owner_pid-based cross-process safe reaping.
The owner_pid file records which hermes process owns a daemon so that
concurrent hermes processes don't reap each other's active browser
sessions. Added to fix orphan accumulation from crashed processes.
"""
def test_alive_owner_is_not_reaped_even_when_untracked(self, fake_tmpdir):
"""Daemon with alive owner_pid is NOT reaped, even if not in our _active_sessions.
This is the core cross-process safety check: Process B scanning while
Process A is using a browser must not kill A's daemon.
"""
from tools.browser_tool import _reap_orphaned_browser_sessions
# Use our own PID as the "owner" — guaranteed alive
d = _make_socket_dir(
fake_tmpdir, "h_alive_owner", pid=12345, owner_pid=os.getpid()
)
kill_calls = []
def mock_kill(pid, sig):
kill_calls.append((pid, sig))
if pid == os.getpid() and sig == 0:
return # real existence check: owner alive
if sig == 0:
return # pretend daemon exists too
# Don't actually kill anything
with patch("os.kill", side_effect=mock_kill):
_reap_orphaned_browser_sessions()
# We should have checked the owner (sig 0) but never tried to kill
# the daemon.
assert (12345, signal.SIGTERM) not in kill_calls
# Dir should still exist
assert d.exists()
def test_dead_owner_triggers_reap(self, fake_tmpdir):
"""Daemon whose owner_pid is dead gets reaped."""
from tools.browser_tool import _reap_orphaned_browser_sessions
# PID 999999999 almost certainly doesn't exist
d = _make_socket_dir(
fake_tmpdir, "h_dead_owner1", pid=12345, owner_pid=999999999
)
kill_calls = []
def mock_kill(pid, sig):
kill_calls.append((pid, sig))
if pid == 999999999 and sig == 0:
raise ProcessLookupError # owner dead
if pid == 12345 and sig == 0:
return # daemon still alive
# SIGTERM to daemon — noop in test
with patch("os.kill", side_effect=mock_kill):
_reap_orphaned_browser_sessions()
# Owner checked (returned dead), daemon checked (alive), daemon killed
assert (999999999, 0) in kill_calls
assert (12345, 0) in kill_calls
assert (12345, signal.SIGTERM) in kill_calls
# Dir cleaned up
assert not d.exists()
def test_corrupt_owner_pid_falls_back_to_legacy(self, fake_tmpdir):
"""Corrupt owner_pid file → fall back to tracked_names check."""
import tools.browser_tool as bt
from tools.browser_tool import _reap_orphaned_browser_sessions
session_name = "h_corrupt_own"
d = _make_socket_dir(fake_tmpdir, session_name, pid=12345)
# Write garbage to owner_pid file
(d / f"{session_name}.owner_pid").write_text("not-a-pid")
# Register session so legacy fallback leaves it alone
bt._active_sessions["task"] = {"session_name": session_name}
kill_calls = []
def mock_kill(pid, sig):
kill_calls.append((pid, sig))
with patch("os.kill", side_effect=mock_kill):
_reap_orphaned_browser_sessions()
# Legacy path took over → tracked → not reaped
assert (12345, signal.SIGTERM) not in kill_calls
assert d.exists()
def test_owner_pid_permission_error_treated_as_alive(self, fake_tmpdir):
"""If os.kill(owner, 0) raises PermissionError, treat owner as alive.
PermissionError means the PID exists but is owned by a different user —
we must not assume the owner is dead (could kill someone else's daemon).
"""
from tools.browser_tool import _reap_orphaned_browser_sessions
d = _make_socket_dir(
fake_tmpdir, "h_perm_owner1", pid=12345, owner_pid=22222
)
kill_calls = []
def mock_kill(pid, sig):
kill_calls.append((pid, sig))
if pid == 22222 and sig == 0:
raise PermissionError("not our user")
with patch("os.kill", side_effect=mock_kill):
_reap_orphaned_browser_sessions()
# Must NOT have tried to kill the daemon
assert (12345, signal.SIGTERM) not in kill_calls
assert d.exists()
def test_write_owner_pid_creates_file_with_current_pid(
self, fake_tmpdir, monkeypatch
):
"""_write_owner_pid(dir, session) writes <session>.owner_pid with os.getpid()."""
import tools.browser_tool as bt
session_name = "h_ownertest01"
socket_dir = fake_tmpdir / f"agent-browser-{session_name}"
socket_dir.mkdir()
bt._write_owner_pid(str(socket_dir), session_name)
owner_pid_file = socket_dir / f"{session_name}.owner_pid"
assert owner_pid_file.exists()
assert owner_pid_file.read_text().strip() == str(os.getpid())
def test_write_owner_pid_is_idempotent(self, fake_tmpdir):
"""Calling _write_owner_pid twice leaves a single owner_pid file."""
import tools.browser_tool as bt
session_name = "h_idempot1234"
socket_dir = fake_tmpdir / f"agent-browser-{session_name}"
socket_dir.mkdir()
bt._write_owner_pid(str(socket_dir), session_name)
bt._write_owner_pid(str(socket_dir), session_name)
files = list(socket_dir.glob("*.owner_pid"))
assert len(files) == 1
assert files[0].read_text().strip() == str(os.getpid())
def test_write_owner_pid_swallows_oserror(self, fake_tmpdir, monkeypatch):
"""OSError (e.g. permission denied) doesn't propagate — the reaper
falls back to the legacy tracked_names heuristic in that case.
"""
import tools.browser_tool as bt
def raise_oserror(*a, **kw):
raise OSError("permission denied")
monkeypatch.setattr("builtins.open", raise_oserror)
# Must not raise
bt._write_owner_pid(str(fake_tmpdir), "h_readonly123")
def test_run_browser_command_calls_write_owner_pid(
self, fake_tmpdir, monkeypatch
):
"""_run_browser_command wires _write_owner_pid after mkdir."""
import tools.browser_tool as bt
session_name = "h_wiringtest1"
# Short-circuit Popen so we exit after the owner_pid write
class _FakePopen:
def __init__(self, *a, **kw):
raise RuntimeError("short-circuit after owner_pid")
monkeypatch.setattr(bt.subprocess, "Popen", _FakePopen)
monkeypatch.setattr(bt, "_find_agent_browser", lambda: "/bin/true")
monkeypatch.setattr(
bt, "_requires_real_termux_browser_install", lambda *a: False
)
monkeypatch.setattr(
bt, "_get_session_info",
lambda task_id: {"session_name": session_name},
)
calls = []
orig_write = bt._write_owner_pid
def _spy(*a, **kw):
calls.append(a)
orig_write(*a, **kw)
monkeypatch.setattr(bt, "_write_owner_pid", _spy)
with patch("tools.browser_tool._socket_safe_tmpdir", return_value=str(fake_tmpdir)):
try:
bt._run_browser_command(task_id="test_task", command="goto", args=[])
except Exception:
pass
assert calls, "_run_browser_command must call _write_owner_pid"
# First positional arg is the socket_dir, second is the session_name
socket_dir_arg, session_name_arg = calls[0][0], calls[0][1]
assert session_name_arg == session_name
assert session_name in socket_dir_arg
class TestEmergencyCleanupRunsReaper:
"""Verify atexit-registered cleanup sweeps orphans even without an active session."""
def test_emergency_cleanup_calls_reaper(self, fake_tmpdir, monkeypatch):
"""_emergency_cleanup_all_sessions must call _reap_orphaned_browser_sessions."""
import tools.browser_tool as bt
# Reset the _cleanup_done flag so the cleanup actually runs
monkeypatch.setattr(bt, "_cleanup_done", False)
reaper_called = []
orig_reaper = bt._reap_orphaned_browser_sessions
def _spy_reaper():
reaper_called.append(True)
orig_reaper()
monkeypatch.setattr(bt, "_reap_orphaned_browser_sessions", _spy_reaper)
# No active sessions — reaper should still run
bt._emergency_cleanup_all_sessions()
assert reaper_called, (
"Reaper must run on exit even with no active sessions"
)