feat: add independent platform modules and multi-provider storage

middleware/rateLimit.go

@@ -13,6 +13,7 @@ import (
 )
 
 type RateLimitConfig struct {
+	Backend RateLimitBackend            `json:"-"`
 	Rate    float64                     `json:"rate"` // Tokens per second, per key.
 	Burst   int                         `json:"burst"`
 	MaxKeys int                         `json:"maxKeys"`
@@ -64,7 +65,17 @@ func (l *RateLimiter) Middleware() httpx.Middleware {
 			if key == "" || len(key) > 1024 {
 				return apierrors.BadRequest("INVALID_RATE_KEY", "invalid rate limit key")
 			}
-			delay, full := l.allow(key)
+			var delay time.Duration
+			var full bool
+			if l.config.Backend != nil {
+				var err error
+				delay, err = l.config.Backend.Take(c.Context(), key)
+				if err != nil {
+					return apierrors.New(503, "RATE_LIMIT_UNAVAILABLE", "rate limiter unavailable").WithCause(err)
+				}
+			} else {
+				delay, full = l.allow(key)
+			}
 			if full {
 				return apierrors.New(503, "RATE_LIMIT_CAPACITY", "rate limiter capacity reached")
 			}