left4me/l4d2host/tests/test_lifecycle.py
mwiegand ff6ce7b091
refactor(l4d2-host): unmount via ExecStopPost — single code path mirroring mount
Symmetric with the earlier mount cleanup (commits 519567e..a982995). Until
now, the unit's ExecStartPre handled mount but the Python side still drove
unmount: stop_instance and _purge_instance both called _mounter.unmount,
which wrapped sudo + the helper. Two code paths for two halves of the
same lifecycle.

Move unmount into the unit:

- ExecStopPost=+/usr/local/libexec/left4me/left4me-overlay umount %i
  (ExecStopPost, not ExecStop, so it runs after the cgroup is cleared;
  ExecStop runs while srcds is alive and would EBUSY the umount syscall.)
- Helper's umount verb is now idempotent (mirrors mount): if merged
  isn't a mount point, return early. PRINT_ONLY mode bypasses both
  short-circuits so the unit tests still exercise the full nsenter argv.

Drop the dead Python machinery:

- _mounter.unmount(...) calls in stop_instance and _purge_instance
- _mounter global + KernelOverlayFSMounter import
- The whole l4d2host/fs/ package (OverlayMounter ABC + KernelOverlayFSMounter
  class) — no production callers, just self-tests
- l4d2host/tests/test_kernel_overlayfs.py
- test_stop_succeeds_when_unmount_fails / test_delete_succeeds_when_unmount_fails
  (tested Python-side unmount-failure tolerance that no longer exists)
- The l4d2host.fs.kernel_overlayfs.run_command monkeypatches in lifecycle tests

After this, the only thing start_instance does beyond cfg-staging is ask
systemd to enable+start the unit. stop/delete/reset only ask systemd to
disable; the overlay lifecycle lives entirely in the unit file.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-09 13:09:52 +02:00

188 lines
7.2 KiB
Python

import subprocess
from pathlib import Path
import pytest
from l4d2host.instances import (
delete_instance,
initialize_instance,
reset_instance,
start_instance,
stop_instance,
)
def test_start_order(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
calls: list[list[str]] = []
def fake_run_command(cmd, **kwargs):
del kwargs
calls.append(list(cmd))
instance_dir = tmp_path / "instances" / "alpha"
runtime_dir = tmp_path / "runtime" / "alpha"
(runtime_dir / "merged" / "left4dead2" / "cfg").mkdir(parents=True, exist_ok=True)
instance_dir.mkdir(parents=True, exist_ok=True)
(instance_dir / "instance.env").write_text(
"L4D2_PORT=27015\nL4D2_ARGS=-tickrate 100\nL4D2_LOWERDIRS=/x:/y\n"
)
(instance_dir / "server.cfg").write_text("sv_consistency 1")
(instance_dir / "spec.yaml").write_text("port: 27015\noverlays: [x, y]\n")
monkeypatch.setattr("l4d2host.service_control.run_command", fake_run_command)
start_instance("alpha", root=tmp_path)
# The mount is now driven by the unit's ExecStartPre (single source of
# truth), so start_instance only stages the cfgs and asks systemd to
# enable+start the unit.
assert calls == [
["sudo", "-n", "/usr/local/libexec/left4me/left4me-systemctl", "enable", "alpha"],
]
def test_start_copies_per_overlay_aliases_and_sweeps_stale(
tmp_path: Path, monkeypatch: pytest.MonkeyPatch
) -> None:
def fake_run_command(cmd, **kwargs):
del cmd, kwargs
instance_dir = tmp_path / "instances" / "alpha"
runtime_dir = tmp_path / "runtime" / "alpha"
upper_cfg_dir = runtime_dir / "upper" / "left4dead2" / "cfg"
upper_cfg_dir.mkdir(parents=True, exist_ok=True)
(runtime_dir / "merged").mkdir(parents=True, exist_ok=True)
instance_dir.mkdir(parents=True, exist_ok=True)
(instance_dir / "instance.env").write_text(
"L4D2_PORT=27015\nL4D2_ARGS=\nL4D2_LOWERDIRS=/x\n"
)
(instance_dir / "server.cfg").write_text("exec server_overlay_5\n")
(instance_dir / "spec.yaml").write_text(
"port: 27015\n"
"overlays:\n"
" - {path: '5', alias: overlay_5}\n"
" - {path: '6', alias: overlay_6}\n"
" - path: '7'\n"
)
src_5 = tmp_path / "overlays" / "5" / "left4dead2" / "cfg"
src_5.mkdir(parents=True, exist_ok=True)
(src_5 / "server.cfg").write_text("sv_consistency 1\n")
src_7 = tmp_path / "overlays" / "7" / "left4dead2" / "cfg"
src_7.mkdir(parents=True, exist_ok=True)
(src_7 / "server.cfg").write_text("ignored: alias not set\n")
(upper_cfg_dir / "server_orphan.cfg").write_text("from previous start\n")
monkeypatch.setattr("l4d2host.service_control.run_command", fake_run_command)
start_instance("alpha", root=tmp_path)
assert (upper_cfg_dir / "server.cfg").read_text() == "exec server_overlay_5\n"
assert (upper_cfg_dir / "server_overlay_5.cfg").read_text() == "sv_consistency 1\n"
assert not (upper_cfg_dir / "server_overlay_6.cfg").exists(), "no source server.cfg → no alias"
assert not (upper_cfg_dir / "server_orphan.cfg").exists(), "stale alias must be swept"
assert not (upper_cfg_dir / "server_overlay_7.cfg").exists(), "no alias in spec → no copy"
def test_delete_missing_is_noop(tmp_path: Path) -> None:
delete_instance("missing", root=tmp_path)
def test_delete_succeeds_when_stop_service_fails(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
calls: list[list[str]] = []
def fake_run_command(cmd, **kwargs):
del kwargs
calls.append(list(cmd))
if cmd[:2] == ["sudo", "-n"] and "left4me-systemctl" in cmd[2] and "disable" in cmd:
raise subprocess.CalledProcessError(
returncode=5,
cmd=list(cmd),
stderr="Unit left4me-server@alpha.service not loaded.",
)
(tmp_path / "instances" / "alpha").mkdir(parents=True)
(tmp_path / "runtime" / "alpha" / "merged").mkdir(parents=True)
monkeypatch.setattr("l4d2host.service_control.run_command", fake_run_command)
delete_instance("alpha", root=tmp_path)
assert not (tmp_path / "instances" / "alpha").exists()
assert not (tmp_path / "runtime" / "alpha").exists()
@pytest.mark.parametrize("bad_name", ["..", "../escape", "foo/bar", " foo", "Foo"])
def test_lifecycle_rejects_unsafe_instance_names(tmp_path: Path, bad_name: str) -> None:
for func in (start_instance, stop_instance, delete_instance, reset_instance):
with pytest.raises(ValueError):
func(bad_name, root=tmp_path)
with pytest.raises(ValueError):
initialize_instance(bad_name, tmp_path / "spec.yaml", root=tmp_path)
assert not (tmp_path / "instances").exists()
assert not (tmp_path / "runtime").exists()
def test_reset_stops_unmounts_and_removes_dirs(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
calls: list[list[str]] = []
def fake_run_command(cmd, **kwargs):
del kwargs
calls.append(list(cmd))
instance_dir = tmp_path / "instances" / "alpha"
runtime_dir = tmp_path / "runtime" / "alpha"
instance_dir.mkdir(parents=True)
(runtime_dir / "merged").mkdir(parents=True)
(instance_dir / "instance.env").write_text("L4D2_PORT=27015\n")
(runtime_dir / "upper" / "logs").mkdir(parents=True)
(runtime_dir / "upper" / "logs" / "console.log").write_text("noise")
monkeypatch.setattr("l4d2host.service_control.run_command", fake_run_command)
reset_instance("alpha", root=tmp_path)
assert not instance_dir.exists()
assert not runtime_dir.exists()
assert any("left4me-systemctl" in arg for cmd in calls for arg in cmd)
assert any("disable" in cmd for cmd in calls)
def test_reset_on_never_initialized_is_noop(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
"""No instance/runtime directories yet — reset should still attempt the
stop+unmount (both suppressed on failure) and not raise."""
def fake_run_command(cmd, **kwargs):
del kwargs
if "disable" in cmd:
raise subprocess.CalledProcessError(returncode=5, cmd=list(cmd), stderr="not loaded")
monkeypatch.setattr("l4d2host.service_control.run_command", fake_run_command)
reset_instance("alpha", root=tmp_path)
assert not (tmp_path / "instances" / "alpha").exists()
assert not (tmp_path / "runtime" / "alpha").exists()
def test_delete_stopped_instance_removes_dirs(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
calls: list[list[str]] = []
def fake_run_command(cmd, **kwargs):
del kwargs
calls.append(list(cmd))
(tmp_path / "instances" / "alpha").mkdir(parents=True)
(tmp_path / "runtime" / "alpha" / "merged").mkdir(parents=True)
monkeypatch.setattr("l4d2host.service_control.run_command", fake_run_command)
delete_instance("alpha", root=tmp_path)
assert not (tmp_path / "instances" / "alpha").exists()
assert not (tmp_path / "runtime" / "alpha").exists()
assert ["sudo", "-n", "/usr/local/libexec/left4me/left4me-systemctl", "disable", "alpha"] in calls
# test_stop_succeeds_when_unmount_fails / test_delete_succeeds_when_unmount_fails
# were removed when the Python-side unmount was dropped: the unit's
# ExecStopPost is now the single code path for unmount, so there's no
# Python-side failure to tolerate.