Files

54 lines
1.2 KiB
Go

package middleware
import (
"net/http"
"sync"
"time"
"github.com/gin-gonic/gin"
)
type rateWindow struct {
start time.Time
count int
}
var rateWindows sync.Map
var rateMu sync.Mutex
// RateLimitByIP applies a fixed-window limit to public endpoints.
// A shared gateway limiter is still needed when running multiple replicas.
func RateLimitByIP(max int, window time.Duration) gin.HandlerFunc {
if max < 1 {
max = 1
}
if window <= 0 {
window = time.Minute
}
return func(c *gin.Context) {
key := c.Request.Method + ":" + c.FullPath() + ":" + c.ClientIP()
now := time.Now()
rateMu.Lock()
allowed := false
var current rateWindow
if raw, ok := rateWindows.Load(key); ok {
current, _ = raw.(rateWindow)
}
if current.start.IsZero() || now.Sub(current.start) >= window {
current = rateWindow{start: now, count: 1}
allowed = true
} else if current.count < max {
current.count++
allowed = true
}
rateWindows.Store(key, current)
rateMu.Unlock()
if !allowed {
c.Header("Retry-After", "60")
c.AbortWithStatusJSON(http.StatusTooManyRequests, gin.H{"code": 429, "message": "请求过于频繁,请稍后重试"})
return
}
c.Next()
}
}