add logging

backend/core/middleware.py

@@ -0,0 +1,120 @@
+"""
+AuditLogMiddleware
+──────────────────
+Перехватывает мутирующие HTTP-запросы (POST / PUT / PATCH / DELETE),
+пишет запись в таблицу action_logs после того как ответ уже отправлен клиенту.
+Таким образом, запись в БД не блокирует основной поток ответа.
+
+Что логируется:
+  • Метод + путь            → action  ("POST /api/tickets/book")
+  • IP-адрес                → ip_address (X-Forwarded-For → client.host)
+  • user_id из JWT-токена   → user_id (None для анонимных запросов)
+  • HTTP-статус ответа      → details["status_code"]
+
+Что пропускается:
+  • GET, HEAD, OPTIONS
+  • /docs, /redoc, /openapi.json, /metrics, /api/health
+"""
+
+import logging
+from typing import Any
+
+import jwt
+from starlette.middleware.base import BaseHTTPMiddleware
+from starlette.requests import Request
+from starlette.responses import Response
+
+from core.security import SECRET_KEY, ALGORITHM
+from database.models import ActionLog
+from database.session import async_session
+
+log = logging.getLogger("audit")
+
+# ─── Paths that are never interesting to audit ────────────────────────────────
+
+_SKIP_PREFIXES: tuple[str, ...] = (
+    "/docs",
+    "/redoc",
+    "/openapi.json",
+    "/metrics",
+    "/api/health",
+)
+
+# Only log requests that can change state
+_AUDIT_METHODS: frozenset[str] = frozenset({"POST", "PUT", "PATCH", "DELETE"})
+
+
+# ─── Helpers ──────────────────────────────────────────────────────────────────
+
+def _extract_user_id(request: Request) -> int | None:
+    """
+    Try to decode the Bearer JWT and return the subject as int.
+    Returns None if the header is absent, malformed, or expired.
+    """
+    auth_header = request.headers.get("Authorization", "")
+    if not auth_header.startswith("Bearer "):
+        return None
+    token = auth_header.removeprefix("Bearer ").strip()
+    try:
+        payload: dict[str, Any] = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
+        sub = payload.get("sub")
+        return int(sub) if sub is not None else None
+    except (jwt.PyJWTError, ValueError, TypeError):
+        return None
+
+
+def _extract_ip(request: Request) -> str | None:
+    """
+    Prefer X-Forwarded-For (set by Traefik / Nginx reverse proxy).
+    Fall back to the direct TCP peer address.
+    """
+    forwarded_for = request.headers.get("X-Forwarded-For")
+    if forwarded_for:
+        # X-Forwarded-For can be a comma-separated list; the first entry is the client IP
+        return forwarded_for.split(",")[0].strip()
+    if request.client:
+        return request.client.host
+    return None
+
+
+# ─── Middleware ───────────────────────────────────────────────────────────────
+
+class AuditLogMiddleware(BaseHTTPMiddleware):
+    async def dispatch(self, request: Request, call_next: Any) -> Response:
+        # 1. Let the request go through and collect the response first
+        response: Response = await call_next(request)
+
+        # 2. Decide whether to log
+        method = request.method.upper()
+        path = request.url.path
+
+        if method not in _AUDIT_METHODS:
+            return response
+
+        if any(path.startswith(prefix) for prefix in _SKIP_PREFIXES):
+            return response
+
+        # 3. Extract metadata (cheap, no DB involved)
+        user_id = _extract_user_id(request)
+        ip_address = _extract_ip(request)
+        action = f"{method} {path}"
+        details: dict[str, Any] = {"status_code": response.status_code}
+
+        # 4. Write the audit record asynchronously — after the response is ready,
+        #    so latency is not affected. Errors here must not propagate to the client.
+        try:
+            async with async_session() as session:
+                session.add(
+                    ActionLog(
+                        user_id=user_id,
+                        action=action,
+                        ip_address=ip_address,
+                        details=details,
+                    )
+                )
+                await session.commit()
+        except Exception:
+            # Audit failure must never break the API
+            log.exception("Failed to write audit log for %s %s", method, path)
+
+        return response