steam-backlog-enforcer/steam_backlog_enforcer/tests/test_library_hider.py
Krzysztof kuhy Rudnicki 21fe2f7742 Stop the enforcer launching Steam and notifications as root
The enforce service runs as root (no User=) but sets DISPLAY=:0, so any GUI
it starts lands on the desktop session. Two resolvers disagreed about who to
drop privileges to:

  library_hider._resolve_desktop_user()  read STEAM_ENFORCER_DESKTOP_USER
  game_install._get_real_user()          read only SUDO_USER or USER

systemd sets neither of the latter, so _get_real_user() returned None under
the service and every `geteuid() == 0 and real_user and ...` guard fell
through to running as root. Steam answered with a zenity modal ("Cannot run
as root user", /usr/lib/steam/steam:261) on screen.

Confirmed from the live process tree: root `bash /usr/lib/steam/steam
-cef-disable-gpu ... steam://install/618510` with a root zenity child. It
never reached the journal, because that text goes to zenity and _run_as_user
sends child output to DEVNULL.

- _desktop_env: add resolve_desktop_user/desktop_uid/desktop_user_cmd. Only
  the argv builder is shared, never the spawn call: tests/_no_subprocess.py
  patches subprocess per module by name, so a spawn site in an unpatched
  module could fire a real `sudo -u kuhy steam`.
- game_install._get_real_user: delegate to the shared resolver. This alone
  also fixes the root `steam -silent` in _ensure_steam_running and the
  no-op os.chown on new appmanifests.
- _trigger_steam_install / enforcer.send_notification: drop privileges.
  send_notification had no DBUS_SESSION_BUS_ADDRESS, so it silently reached
  nobody for all six of its callers.
- _run_as_user: fail closed. Running unchanged as root when no desktop user
  resolves is what put the modal on screen; refuse and log instead.

Also stop the retry storm behind it. steamapps does not exist (Steam has
never completed sign-in), so is_game_installed() was always False and the
loop re-triggered every allowed game every pass: 1656 attempts in 30
minutes, service RSS 1.5 GB (peak 4.3 GB), a FileNotFoundError traceback
each time. Guard install_game and _reinstall_missing_allowed on
steam_library_ready() -- a missing library means no install can succeed by
any route, so this is a correctness check rather than a tuned retry limit.

The module splits here are forced by the pre-commit 250-line gate, which
blocks any commit touching an over-cap file: game_install, library_hider and
_enforce_loop were already over before this change. They are split by
responsibility (_cdp transport, _steam_launch lifecycle, _steam_process
spawning, _steam_errors, _steam_client, _game_names, game_uninstall,
_enforce_steps, _owned_apps_cache, _echo, _protected_apps). game_install and
library_hider re-export their old public names, so the 15 modules that
import from them are untouched by this commit.

Verified as real root under the unit's environment: argv is now
`sudo -u kuhy env DISPLAY=:0 ... xdg-open steam://install/...` for both the
installer and notify-send; three enforce passes spawn no process and log
once; _run_as_user refuses with no desktop user. After restart: 0 retries,
0 tracebacks, 0 root-owned files under ~/.local/share/Steam, RSS 342 MB.

1311 tests pass. _desktop_env and _steam_state at 100% branch coverage.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016A1EYiv7e7HGhET84oa9M3
2026-08-24 13:55:44 +02:00

124 lines
3.6 KiB
Python

"""Tests for library_hider module."""
from __future__ import annotations
import asyncio
import json
from unittest.mock import AsyncMock, MagicMock, patch
import pytest
from steam_backlog_enforcer._cdp import (
_cdp_result_value,
_evaluate_js,
_evaluate_js_async,
_get_shared_js_ws_url,
)
class TestGetSharedJsWsUrl:
"""Tests for _get_shared_js_ws_url."""
def test_finds_url(self) -> None:
targets = [
{
"title": "SharedJSContext",
"webSocketDebuggerUrl": "ws://127.0.0.1:8080/x",
},
{"title": "Other", "webSocketDebuggerUrl": "ws://other"},
]
mock_resp = MagicMock()
mock_resp.json.return_value = targets
with patch(
"steam_backlog_enforcer._cdp.requests.get",
return_value=mock_resp,
):
result = _get_shared_js_ws_url()
assert result == "ws://127.0.0.1:8080/x"
def test_no_shared_context(self) -> None:
targets = [{"title": "Other", "webSocketDebuggerUrl": "ws://other"}]
mock_resp = MagicMock()
mock_resp.json.return_value = targets
with patch(
"steam_backlog_enforcer._cdp.requests.get",
return_value=mock_resp,
):
assert _get_shared_js_ws_url() is None
def test_connection_error(self) -> None:
with patch(
"steam_backlog_enforcer._cdp.requests.get",
side_effect=OSError,
):
assert _get_shared_js_ws_url() is None
class TestEvaluateJsAsync:
"""Tests for _evaluate_js_async."""
def test_success(self) -> None:
mock_ws = AsyncMock()
mock_ws.send = AsyncMock()
mock_ws.recv = AsyncMock(
return_value=json.dumps({"result": {"result": {"value": "ok"}}})
)
mock_ws.__aenter__ = AsyncMock(return_value=mock_ws)
mock_ws.__aexit__ = AsyncMock(return_value=False)
with patch(
"steam_backlog_enforcer._cdp.websockets.connect",
return_value=mock_ws,
):
result = asyncio.run(_evaluate_js_async("ws://test", "1+1"))
assert result["result"]["result"]["value"] == "ok"
class TestEvaluateJs:
"""Tests for _evaluate_js."""
def test_success(self) -> None:
with (
patch(
"steam_backlog_enforcer._cdp._get_shared_js_ws_url",
return_value="ws://test",
),
patch(
"steam_backlog_enforcer._cdp.asyncio.run",
return_value={"result": {"result": {"value": "ok"}}},
),
):
result = _evaluate_js("1+1")
assert result["result"]["result"]["value"] == "ok"
def test_no_ws_url(self) -> None:
with (
patch(
"steam_backlog_enforcer._cdp._get_shared_js_ws_url",
return_value=None,
),
pytest.raises(RuntimeError, match="SharedJSContext not found"),
):
_evaluate_js("1+1")
class TestCdpResultValue:
"""Tests for _cdp_result_value."""
def test_extracts_value(self) -> None:
result = {"result": {"result": {"value": "hello"}}}
assert _cdp_result_value(result) == "hello"
def test_exception(self) -> None:
result = {
"result": {
"result": {"description": "Error!"},
"exceptionDetails": {},
}
}
with pytest.raises(RuntimeError, match="JS evaluation error"):
_cdp_result_value(result)
def test_empty(self) -> None:
assert _cdp_result_value({}) == ""