复制项目

internal/api/ratelimit.go

@@ -0,0 +1,83 @@
+package api
+
+import (
+	"fmt"
+	"math"
+	"net/http"
+	"strconv"
+	"time"
+
+	"github.com/gin-gonic/gin"
+
+	"github.com/openimsdk/tools/apiresp"
+	"github.com/openimsdk/tools/errs"
+	"github.com/openimsdk/tools/log"
+	"github.com/openimsdk/tools/stability/ratelimit"
+	"github.com/openimsdk/tools/stability/ratelimit/bbr"
+)
+
+type RateLimiter struct {
+	Enable       bool          `yaml:"enable"`
+	Window       time.Duration `yaml:"window"`       // time duration per window
+	Bucket       int           `yaml:"bucket"`       // bucket number for each window
+	CPUThreshold int64         `yaml:"cpuThreshold"` // CPU threshold; valid range 0–1000 (1000 = 100%)
+}
+
+func RateLimitMiddleware(config *RateLimiter) gin.HandlerFunc {
+	if !config.Enable {
+		return func(c *gin.Context) {
+			c.Next()
+		}
+	}
+
+	limiter := bbr.NewBBRLimiter(
+		bbr.WithWindow(config.Window),
+		bbr.WithBucket(config.Bucket),
+		bbr.WithCPUThreshold(config.CPUThreshold),
+	)
+
+	return func(c *gin.Context) {
+		status := limiter.Stat()
+
+		c.Header("X-BBR-CPU", strconv.FormatInt(status.CPU, 10))
+		c.Header("X-BBR-MinRT", strconv.FormatInt(status.MinRt, 10))
+		c.Header("X-BBR-MaxPass", strconv.FormatInt(status.MaxPass, 10))
+		c.Header("X-BBR-MaxInFlight", strconv.FormatInt(status.MaxInFlight, 10))
+		c.Header("X-BBR-InFlight", strconv.FormatInt(status.InFlight, 10))
+
+		done, err := limiter.Allow()
+		if err != nil {
+
+			c.Header("X-RateLimit-Policy", "BBR")
+			c.Header("Retry-After", calculateBBRRetryAfter(status))
+			c.Header("X-RateLimit-Limit", strconv.FormatInt(status.MaxInFlight, 10))
+			c.Header("X-RateLimit-Remaining", "0") // There is no concept of remaining quota in BBR.
+
+			fmt.Println("rate limited:", err, "path:", c.Request.URL.Path)
+			log.ZWarn(c, "rate limited", err, "path", c.Request.URL.Path)
+			c.AbortWithStatus(http.StatusTooManyRequests)
+			apiresp.GinError(c, errs.NewCodeError(http.StatusTooManyRequests, "too many requests, please try again later"))
+			return
+		}
+
+		c.Next()
+		done(ratelimit.DoneInfo{})
+	}
+}
+
+func calculateBBRRetryAfter(status bbr.Stat) string {
+	loadRatio := float64(status.CPU) / float64(status.CPU)
+
+	if loadRatio < 0.8 {
+		return "1"
+	}
+	if loadRatio < 0.95 {
+		return "2"
+	}
+
+	backoff := 1 + int64(math.Pow(loadRatio-0.95, 2)*50)
+	if backoff > 5 {
+		backoff = 5
+	}
+	return strconv.FormatInt(backoff, 10)
+}