Stage 7: configuration view — backend service, routers, tests, and frontend
- config_service.py: read/write jail config via asyncio.gather, global settings, in-process regex validation, log preview via _read_tail_lines - server_service.py: read/write server settings, flush logs - config router: 9 endpoints for jail/global config, regex-test, logpath management, log preview - server router: GET/PUT settings, POST flush-logs - models/config.py expanded with JailConfig, GlobalConfigUpdate, LogPreview* models - 285 tests pass (68 new), ruff clean, mypy clean (44 files) - Frontend: types/config.ts, api/config.ts, hooks/useConfig.ts, ConfigPage.tsx full implementation (Jails accordion editor, Global config, Server settings, Regex Tester with preview) - Fixed pre-existing frontend lint: JSX.Element → React.JSX.Element (10 files), void/promise patterns in useServerStatus + useJails, no-misused-spread in client.ts, eslint.config.ts self-excluded
This commit is contained in:
611
backend/app/services/config_service.py
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611
backend/app/services/config_service.py
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@@ -0,0 +1,611 @@
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"""Configuration inspection and editing service.
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Provides methods to read and update fail2ban jail configuration and global
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server settings via the Unix domain socket. Regex validation is performed
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locally with Python's :mod:`re` module before any write is sent to the daemon
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so that invalid patterns are rejected early.
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Architecture note: this module is a pure service — it contains **no**
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HTTP/FastAPI concerns. All results are returned as Pydantic models so
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routers can serialise them directly.
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"""
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from __future__ import annotations
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import asyncio
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import contextlib
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import re
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from pathlib import Path
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from typing import Any
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import structlog
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from app.models.config import (
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AddLogPathRequest,
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GlobalConfigResponse,
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GlobalConfigUpdate,
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JailConfig,
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JailConfigListResponse,
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JailConfigResponse,
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JailConfigUpdate,
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LogPreviewLine,
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LogPreviewRequest,
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LogPreviewResponse,
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RegexTestRequest,
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RegexTestResponse,
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)
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from app.utils.fail2ban_client import Fail2BanClient
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log: structlog.stdlib.BoundLogger = structlog.get_logger()
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_SOCKET_TIMEOUT: float = 10.0
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# ---------------------------------------------------------------------------
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# Custom exceptions
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# ---------------------------------------------------------------------------
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class JailNotFoundError(Exception):
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"""Raised when a requested jail name does not exist in fail2ban."""
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def __init__(self, name: str) -> None:
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"""Initialise with the jail name that was not found.
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Args:
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name: The jail name that could not be located.
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"""
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self.name: str = name
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super().__init__(f"Jail not found: {name!r}")
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class ConfigValidationError(Exception):
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"""Raised when a configuration value fails validation before writing."""
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class ConfigOperationError(Exception):
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"""Raised when a configuration write command fails."""
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# ---------------------------------------------------------------------------
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# Internal helpers (mirrored from jail_service for isolation)
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# ---------------------------------------------------------------------------
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def _ok(response: Any) -> Any:
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"""Extract payload from a fail2ban ``(return_code, data)`` response.
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Args:
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response: Raw value returned by :meth:`~Fail2BanClient.send`.
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Returns:
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The payload ``data`` portion of the response.
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Raises:
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ValueError: If the return code indicates an error.
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"""
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try:
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code, data = response
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except (TypeError, ValueError) as exc:
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raise ValueError(f"Unexpected fail2ban response shape: {response!r}") from exc
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if code != 0:
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raise ValueError(f"fail2ban returned error code {code}: {data!r}")
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return data
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def _to_dict(pairs: Any) -> dict[str, Any]:
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"""Convert a list of ``(key, value)`` pairs to a plain dict."""
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if not isinstance(pairs, (list, tuple)):
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return {}
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result: dict[str, Any] = {}
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for item in pairs:
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try:
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k, v = item
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result[str(k)] = v
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except (TypeError, ValueError):
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pass
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return result
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def _ensure_list(value: Any) -> list[str]:
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"""Coerce a fail2ban ``get`` result to a list of strings."""
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if value is None:
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return []
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if isinstance(value, str):
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return [value] if value.strip() else []
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if isinstance(value, (list, tuple)):
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return [str(v) for v in value if v is not None]
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return [str(value)]
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async def _safe_get(
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client: Fail2BanClient,
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command: list[Any],
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default: Any = None,
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) -> Any:
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"""Send a command and return *default* if it fails."""
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try:
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return _ok(await client.send(command))
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except Exception:
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return default
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def _is_not_found_error(exc: Exception) -> bool:
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"""Return ``True`` if *exc* signals an unknown jail."""
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msg = str(exc).lower()
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return any(
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phrase in msg
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for phrase in ("unknown jail", "no jail", "does not exist", "not found")
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)
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def _validate_regex(pattern: str) -> str | None:
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"""Try to compile *pattern* and return an error message if invalid.
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Args:
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pattern: A regex pattern string to validate.
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Returns:
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``None`` if valid, or an error message string if the pattern is broken.
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"""
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try:
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re.compile(pattern)
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return None
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except re.error as exc:
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return str(exc)
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# ---------------------------------------------------------------------------
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# Public API — read jail configuration
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# ---------------------------------------------------------------------------
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async def get_jail_config(socket_path: str, name: str) -> JailConfigResponse:
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"""Return the editable configuration for a single jail.
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Args:
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socket_path: Path to the fail2ban Unix domain socket.
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name: Jail name.
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Returns:
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:class:`~app.models.config.JailConfigResponse`.
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Raises:
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JailNotFoundError: If *name* is not a known jail.
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~app.utils.fail2ban_client.Fail2BanConnectionError: Socket unreachable.
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"""
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client = Fail2BanClient(socket_path=socket_path, timeout=_SOCKET_TIMEOUT)
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# Verify existence.
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try:
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_ok(await client.send(["status", name, "short"]))
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except ValueError as exc:
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if _is_not_found_error(exc):
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raise JailNotFoundError(name) from exc
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raise
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(
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bantime_raw,
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findtime_raw,
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maxretry_raw,
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failregex_raw,
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ignoreregex_raw,
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logpath_raw,
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datepattern_raw,
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logencoding_raw,
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backend_raw,
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actions_raw,
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) = await asyncio.gather(
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_safe_get(client, ["get", name, "bantime"], 600),
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_safe_get(client, ["get", name, "findtime"], 600),
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_safe_get(client, ["get", name, "maxretry"], 5),
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_safe_get(client, ["get", name, "failregex"], []),
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_safe_get(client, ["get", name, "ignoreregex"], []),
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_safe_get(client, ["get", name, "logpath"], []),
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_safe_get(client, ["get", name, "datepattern"], None),
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_safe_get(client, ["get", name, "logencoding"], "UTF-8"),
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_safe_get(client, ["get", name, "backend"], "polling"),
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_safe_get(client, ["get", name, "actions"], []),
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)
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jail_cfg = JailConfig(
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name=name,
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ban_time=int(bantime_raw or 600),
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find_time=int(findtime_raw or 600),
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max_retry=int(maxretry_raw or 5),
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fail_regex=_ensure_list(failregex_raw),
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ignore_regex=_ensure_list(ignoreregex_raw),
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log_paths=_ensure_list(logpath_raw),
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date_pattern=str(datepattern_raw) if datepattern_raw else None,
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log_encoding=str(logencoding_raw or "UTF-8"),
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backend=str(backend_raw or "polling"),
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actions=_ensure_list(actions_raw),
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)
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log.info("jail_config_fetched", jail=name)
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return JailConfigResponse(jail=jail_cfg)
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async def list_jail_configs(socket_path: str) -> JailConfigListResponse:
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"""Return configuration for all active jails.
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Args:
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socket_path: Path to the fail2ban Unix domain socket.
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Returns:
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:class:`~app.models.config.JailConfigListResponse`.
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Raises:
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~app.utils.fail2ban_client.Fail2BanConnectionError: Socket unreachable.
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"""
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client = Fail2BanClient(socket_path=socket_path, timeout=_SOCKET_TIMEOUT)
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global_status = _to_dict(_ok(await client.send(["status"])))
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jail_list_raw: str = str(global_status.get("Jail list", "") or "").strip()
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jail_names: list[str] = (
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[j.strip() for j in jail_list_raw.split(",") if j.strip()]
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if jail_list_raw
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else []
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)
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if not jail_names:
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return JailConfigListResponse(jails=[], total=0)
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responses: list[JailConfigResponse] = await asyncio.gather(
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*[get_jail_config(socket_path, name) for name in jail_names],
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return_exceptions=False,
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)
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jails = [r.jail for r in responses]
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log.info("jail_configs_listed", count=len(jails))
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return JailConfigListResponse(jails=jails, total=len(jails))
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# ---------------------------------------------------------------------------
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# Public API — write jail configuration
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# ---------------------------------------------------------------------------
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async def update_jail_config(
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socket_path: str,
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name: str,
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update: JailConfigUpdate,
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) -> None:
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"""Apply *update* to the configuration of a running jail.
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Each non-None field in *update* is sent as a separate ``set`` command.
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Regex patterns are validated locally before any write is sent.
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Args:
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socket_path: Path to the fail2ban Unix domain socket.
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name: Jail name.
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update: Partial update payload.
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Raises:
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JailNotFoundError: If *name* is not a known jail.
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ConfigValidationError: If a regex pattern fails to compile.
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ConfigOperationError: If a ``set`` command is rejected by fail2ban.
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~app.utils.fail2ban_client.Fail2BanConnectionError: Socket unreachable.
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"""
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# Validate all regex patterns before touching the daemon.
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for pattern_list, field in [
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(update.fail_regex, "fail_regex"),
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(update.ignore_regex, "ignore_regex"),
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]:
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if pattern_list is None:
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continue
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for pattern in pattern_list:
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err = _validate_regex(pattern)
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if err:
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raise ConfigValidationError(f"Invalid regex in {field!r}: {err!r} (pattern: {pattern!r})")
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client = Fail2BanClient(socket_path=socket_path, timeout=_SOCKET_TIMEOUT)
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# Verify existence.
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try:
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_ok(await client.send(["status", name, "short"]))
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except ValueError as exc:
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if _is_not_found_error(exc):
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raise JailNotFoundError(name) from exc
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raise
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async def _set(key: str, value: Any) -> None:
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try:
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_ok(await client.send(["set", name, key, value]))
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except ValueError as exc:
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raise ConfigOperationError(f"Failed to set {key!r} = {value!r}: {exc}") from exc
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if update.ban_time is not None:
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await _set("bantime", update.ban_time)
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if update.find_time is not None:
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await _set("findtime", update.find_time)
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if update.max_retry is not None:
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await _set("maxretry", update.max_retry)
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if update.date_pattern is not None:
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await _set("datepattern", update.date_pattern)
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if update.dns_mode is not None:
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await _set("usedns", update.dns_mode)
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if update.enabled is not None:
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await _set("idle", "off" if update.enabled else "on")
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# Replacing regex lists requires deleting old entries then adding new ones.
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if update.fail_regex is not None:
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await _replace_regex_list(client, name, "failregex", update.fail_regex)
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if update.ignore_regex is not None:
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await _replace_regex_list(client, name, "ignoreregex", update.ignore_regex)
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log.info("jail_config_updated", jail=name)
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async def _replace_regex_list(
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client: Fail2BanClient,
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jail: str,
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field: str,
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new_patterns: list[str],
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) -> None:
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"""Replace the full regex list for *field* in *jail*.
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Deletes all existing entries (highest index first to preserve ordering)
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then inserts all *new_patterns* in order.
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Args:
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client: Shared :class:`~app.utils.fail2ban_client.Fail2BanClient`.
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jail: Jail name.
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field: Either ``"failregex"`` or ``"ignoreregex"``.
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new_patterns: Replacement list (may be empty to clear).
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"""
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# Determine current count.
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current_raw = await _safe_get(client, ["get", jail, field], [])
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current: list[str] = _ensure_list(current_raw)
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del_cmd = f"del{field}"
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add_cmd = f"add{field}"
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# Delete in reverse order so indices stay stable.
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for idx in range(len(current) - 1, -1, -1):
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with contextlib.suppress(ValueError):
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_ok(await client.send(["set", jail, del_cmd, idx]))
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# Add new patterns.
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for pattern in new_patterns:
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err = _validate_regex(pattern)
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if err:
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raise ConfigValidationError(f"Invalid regex: {err!r} (pattern: {pattern!r})")
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try:
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_ok(await client.send(["set", jail, add_cmd, pattern]))
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except ValueError as exc:
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raise ConfigOperationError(f"Failed to add {field} pattern: {exc}") from exc
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# ---------------------------------------------------------------------------
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# Public API — global configuration
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# ---------------------------------------------------------------------------
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async def get_global_config(socket_path: str) -> GlobalConfigResponse:
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"""Return fail2ban global configuration settings.
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|
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Args:
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socket_path: Path to the fail2ban Unix domain socket.
|
||||
|
||||
Returns:
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:class:`~app.models.config.GlobalConfigResponse`.
|
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|
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Raises:
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~app.utils.fail2ban_client.Fail2BanConnectionError: Socket unreachable.
|
||||
"""
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client = Fail2BanClient(socket_path=socket_path, timeout=_SOCKET_TIMEOUT)
|
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|
||||
(
|
||||
log_level_raw,
|
||||
log_target_raw,
|
||||
db_purge_age_raw,
|
||||
db_max_matches_raw,
|
||||
) = await asyncio.gather(
|
||||
_safe_get(client, ["get", "loglevel"], "INFO"),
|
||||
_safe_get(client, ["get", "logtarget"], "STDOUT"),
|
||||
_safe_get(client, ["get", "dbpurgeage"], 86400),
|
||||
_safe_get(client, ["get", "dbmaxmatches"], 10),
|
||||
)
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||||
|
||||
return GlobalConfigResponse(
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log_level=str(log_level_raw or "INFO").upper(),
|
||||
log_target=str(log_target_raw or "STDOUT"),
|
||||
db_purge_age=int(db_purge_age_raw or 86400),
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||||
db_max_matches=int(db_max_matches_raw or 10),
|
||||
)
|
||||
|
||||
|
||||
async def update_global_config(socket_path: str, update: GlobalConfigUpdate) -> None:
|
||||
"""Apply *update* to fail2ban global settings.
|
||||
|
||||
Args:
|
||||
socket_path: Path to the fail2ban Unix domain socket.
|
||||
update: Partial update payload.
|
||||
|
||||
Raises:
|
||||
ConfigOperationError: If a ``set`` command is rejected.
|
||||
~app.utils.fail2ban_client.Fail2BanConnectionError: Socket unreachable.
|
||||
"""
|
||||
client = Fail2BanClient(socket_path=socket_path, timeout=_SOCKET_TIMEOUT)
|
||||
|
||||
async def _set_global(key: str, value: Any) -> None:
|
||||
try:
|
||||
_ok(await client.send(["set", key, value]))
|
||||
except ValueError as exc:
|
||||
raise ConfigOperationError(f"Failed to set global {key!r} = {value!r}: {exc}") from exc
|
||||
|
||||
if update.log_level is not None:
|
||||
await _set_global("loglevel", update.log_level.upper())
|
||||
if update.log_target is not None:
|
||||
await _set_global("logtarget", update.log_target)
|
||||
if update.db_purge_age is not None:
|
||||
await _set_global("dbpurgeage", update.db_purge_age)
|
||||
if update.db_max_matches is not None:
|
||||
await _set_global("dbmaxmatches", update.db_max_matches)
|
||||
|
||||
log.info("global_config_updated")
|
||||
|
||||
|
||||
# ---------------------------------------------------------------------------
|
||||
# Public API — regex tester (stateless, no socket)
|
||||
# ---------------------------------------------------------------------------
|
||||
|
||||
|
||||
def test_regex(request: RegexTestRequest) -> RegexTestResponse:
|
||||
"""Test a regex pattern against a sample log line.
|
||||
|
||||
This is a pure in-process operation — no socket communication occurs.
|
||||
|
||||
Args:
|
||||
request: The :class:`~app.models.config.RegexTestRequest` payload.
|
||||
|
||||
Returns:
|
||||
:class:`~app.models.config.RegexTestResponse` with match result.
|
||||
"""
|
||||
try:
|
||||
compiled = re.compile(request.fail_regex)
|
||||
except re.error as exc:
|
||||
return RegexTestResponse(matched=False, groups=[], error=str(exc))
|
||||
|
||||
match = compiled.search(request.log_line)
|
||||
if match is None:
|
||||
return RegexTestResponse(matched=False)
|
||||
|
||||
groups: list[str] = list(match.groups() or [])
|
||||
return RegexTestResponse(matched=True, groups=[str(g) for g in groups if g is not None])
|
||||
|
||||
|
||||
# ---------------------------------------------------------------------------
|
||||
# Public API — log observation
|
||||
# ---------------------------------------------------------------------------
|
||||
|
||||
|
||||
async def add_log_path(
|
||||
socket_path: str,
|
||||
jail: str,
|
||||
req: AddLogPathRequest,
|
||||
) -> None:
|
||||
"""Add a log path to an existing jail.
|
||||
|
||||
Args:
|
||||
socket_path: Path to the fail2ban Unix domain socket.
|
||||
jail: Jail name to which the log path should be added.
|
||||
req: :class:`~app.models.config.AddLogPathRequest` with the path to add.
|
||||
|
||||
Raises:
|
||||
JailNotFoundError: If *jail* is not a known jail.
|
||||
ConfigOperationError: If the command is rejected by fail2ban.
|
||||
~app.utils.fail2ban_client.Fail2BanConnectionError: Socket unreachable.
|
||||
"""
|
||||
client = Fail2BanClient(socket_path=socket_path, timeout=_SOCKET_TIMEOUT)
|
||||
|
||||
try:
|
||||
_ok(await client.send(["status", jail, "short"]))
|
||||
except ValueError as exc:
|
||||
if _is_not_found_error(exc):
|
||||
raise JailNotFoundError(jail) from exc
|
||||
raise
|
||||
|
||||
tail_flag = "tail" if req.tail else "head"
|
||||
try:
|
||||
_ok(await client.send(["set", jail, "addlogpath", req.log_path, tail_flag]))
|
||||
log.info("log_path_added", jail=jail, path=req.log_path)
|
||||
except ValueError as exc:
|
||||
raise ConfigOperationError(f"Failed to add log path {req.log_path!r}: {exc}") from exc
|
||||
|
||||
|
||||
async def preview_log(req: LogPreviewRequest) -> LogPreviewResponse:
|
||||
"""Read the last *num_lines* of a log file and test *fail_regex* against each.
|
||||
|
||||
This operation reads from the local filesystem — no socket is used.
|
||||
|
||||
Args:
|
||||
req: :class:`~app.models.config.LogPreviewRequest`.
|
||||
|
||||
Returns:
|
||||
:class:`~app.models.config.LogPreviewResponse` with line-by-line results.
|
||||
"""
|
||||
# Validate the regex first.
|
||||
try:
|
||||
compiled = re.compile(req.fail_regex)
|
||||
except re.error as exc:
|
||||
return LogPreviewResponse(
|
||||
lines=[],
|
||||
total_lines=0,
|
||||
matched_count=0,
|
||||
regex_error=str(exc),
|
||||
)
|
||||
|
||||
path = Path(req.log_path)
|
||||
if not path.is_file():
|
||||
return LogPreviewResponse(
|
||||
lines=[],
|
||||
total_lines=0,
|
||||
matched_count=0,
|
||||
regex_error=f"File not found: {req.log_path!r}",
|
||||
)
|
||||
|
||||
# Read the last num_lines lines efficiently.
|
||||
try:
|
||||
raw_lines = await asyncio.get_event_loop().run_in_executor(
|
||||
None,
|
||||
_read_tail_lines,
|
||||
str(path),
|
||||
req.num_lines,
|
||||
)
|
||||
except OSError as exc:
|
||||
return LogPreviewResponse(
|
||||
lines=[],
|
||||
total_lines=0,
|
||||
matched_count=0,
|
||||
regex_error=f"Cannot read file: {exc}",
|
||||
)
|
||||
|
||||
result_lines: list[LogPreviewLine] = []
|
||||
matched_count = 0
|
||||
for line in raw_lines:
|
||||
m = compiled.search(line)
|
||||
groups = [str(g) for g in (m.groups() or []) if g is not None] if m else []
|
||||
result_lines.append(LogPreviewLine(line=line, matched=(m is not None), groups=groups))
|
||||
if m:
|
||||
matched_count += 1
|
||||
|
||||
return LogPreviewResponse(
|
||||
lines=result_lines,
|
||||
total_lines=len(result_lines),
|
||||
matched_count=matched_count,
|
||||
)
|
||||
|
||||
|
||||
def _read_tail_lines(file_path: str, num_lines: int) -> list[str]:
|
||||
"""Read the last *num_lines* from *file_path* synchronously.
|
||||
|
||||
Uses a memory-efficient approach that seeks from the end of the file.
|
||||
|
||||
Args:
|
||||
file_path: Absolute path to the log file.
|
||||
num_lines: Number of lines to return.
|
||||
|
||||
Returns:
|
||||
A list of stripped line strings.
|
||||
"""
|
||||
chunk_size = 8192
|
||||
raw_lines: list[bytes] = []
|
||||
with open(file_path, "rb") as fh:
|
||||
fh.seek(0, 2) # seek to end
|
||||
end_pos = fh.tell()
|
||||
if end_pos == 0:
|
||||
return []
|
||||
buf = b""
|
||||
pos = end_pos
|
||||
while len(raw_lines) <= num_lines and pos > 0:
|
||||
read_size = min(chunk_size, pos)
|
||||
pos -= read_size
|
||||
fh.seek(pos)
|
||||
chunk = fh.read(read_size)
|
||||
buf = chunk + buf
|
||||
raw_lines = buf.split(b"\n")
|
||||
# Strip incomplete leading line unless we've read the whole file.
|
||||
if pos > 0 and len(raw_lines) > 1:
|
||||
raw_lines = raw_lines[1:]
|
||||
return [ln.decode("utf-8", errors="replace").rstrip() for ln in raw_lines[-num_lines:] if ln.strip()]
|
||||
Reference in New Issue
Block a user