Initial commit: VPN Telegram bot (sanitized defaults)

services/rate_limit.py

@@ -0,0 +1,41 @@
+"""Простой in-memory rate limit (на процесс)."""
+
+from __future__ import annotations
+
+import time
+from collections import defaultdict
+from threading import Lock
+
+
+class RateLimiter:
+    def __init__(self) -> None:
+        self._hits: dict[str, list[float]] = defaultdict(list)
+        self._lock = Lock()
+
+    def hit(self, key: str, *, limit: int, window_sec: float) -> bool:
+        """True если запрос разрешён, False если превышен лимит."""
+        now = time.monotonic()
+        with self._lock:
+            bucket = self._hits[key]
+            cutoff = now - window_sec
+            self._hits[key] = [t for t in bucket if t >= cutoff]
+            if len(self._hits[key]) >= limit:
+                return False
+            self._hits[key].append(now)
+            return True
+
+
+limiter = RateLimiter()
+
+
+def client_ip(request) -> str:
+    forwarded = (request.headers.get("X-Forwarded-For") or "").split(",")[0].strip()
+    if forwarded:
+        return forwarded
+    peer = request.remote
+    return str(peer or "unknown")
+
+
+def allow(request, bucket: str, *, limit: int = 20, window_sec: float = 60.0) -> bool:
+    ip = client_ip(request)
+    return limiter.hit(f"{bucket}:{ip}", limit=limit, window_sec=window_sec)