Files
BanGUI/backend/app/tasks/rate_limiter_cleanup.py
Lukas 7ec80fdeec refactor(logging): replace structlog with stdlib logging compat layer
- Remove structlog dependency from backend/pyproject.toml
- Add app.utils.logging_compat shim for keyword-arg logging API
- Add app.utils.json_formatter for JSON log output with extra fields
- Update all backend modules to use logging_compat.get_logger()
- Update docstrings in log_sanitizer.py and json_formatter.py
- Update test comment in test_async_utils.py
- Record 406 failing tests in Docs/Tasks.md for tracking
2026-05-10 13:37:54 +02:00

105 lines
3.4 KiB
Python

"""Rate limiter cleanup background task.
Registers an APScheduler job that periodically removes expired rate-limit
entries from the in-memory rate limiter. Without this cleanup, the
rate-limiter state dictionary grows unbounded over long runtimes, eventually
consuming excessive memory.
The cleanup is conservative: it only removes IPs with no recent attempts
(all timestamps outside the rate-limit window), so active or recently-active
IPs are preserved.
Correlation IDs are propagated through the task using :mod:`app.utils.correlation`
so that task logs can be correlated across runs.
"""
from __future__ import annotations
import uuid
from typing import TYPE_CHECKING
from app.utils.logging_compat import get_logger
from app.tasks.timeout_utils import run_with_timeout
from app.utils.correlation import get_correlation_id, reset_correlation_id, set_correlation_id
if TYPE_CHECKING:
from fastapi import FastAPI
log = get_logger(__name__)
#: How often the cleanup job fires (seconds). Chosen to balance memory
#: management against CPU overhead. A 30-minute interval handles typical
#: brute-force attack patterns while staying lightweight.
RATE_LIMITER_CLEANUP_INTERVAL: int = 30 * 60 # 30 minutes
#: Stable APScheduler job ID — ensures re-registration replaces, not duplicates.
JOB_ID: str = "rate_limiter_cleanup"
#: Maximum seconds to allow for rate limiter cleanup to complete.
TASK_TIMEOUT_SECONDS: int = 5
async def _run_cleanup(
app: FastAPI,
correlation_id: str | None = None,
) -> None:
"""Trigger cleanup of expired rate-limiter entries.
Cleans up both the login-specific rate limiter (exponential backoff)
and the global request rate limiter.
Args:
app: The FastAPI application instance (holds the rate limiters).
correlation_id: Optional correlation ID for log correlation.
"""
if correlation_id is None:
correlation_id = str(uuid.uuid4())
token = set_correlation_id(correlation_id)
try:
await _do_cleanup_with_app(app)
finally:
reset_correlation_id(token)
async def _do_cleanup_with_app(app: FastAPI) -> None:
"""Inner cleanup logic that runs with correlation context set."""
async def _do_cleanup() -> None:
global_limiter = getattr(app.state, "global_rate_limiter", None)
if global_limiter is None:
log.warning(
"rate_limiter_cleanup_skipped",
correlation_id=get_correlation_id(),
reason="global_rate_limiter not found on app.state",
)
else:
global_limiter.cleanup_expired()
await run_with_timeout("rate_limiter_cleanup", _do_cleanup(), TASK_TIMEOUT_SECONDS)
def register(app: FastAPI) -> None:
"""Add (or replace) the rate-limiter cleanup job in the application scheduler.
Must be called after the scheduler has been started (i.e., inside the
lifespan handler, after ``scheduler.start()``).
Args:
app: The :class:`fastapi.FastAPI` application instance whose
``app.state.scheduler`` will receive the job.
"""
app.state.scheduler.add_job(
_run_cleanup,
trigger="interval",
seconds=RATE_LIMITER_CLEANUP_INTERVAL,
kwargs={"app": app},
id=JOB_ID,
replace_existing=True,
)
log.info(
"rate_limiter_cleanup_scheduled",
interval_seconds=RATE_LIMITER_CLEANUP_INTERVAL,
)