Golang限流实现与防刷方法解析

package main

import (
    "golang.org/x/time/rate"
    "net/http"
    "time"
)

var limiter = rate.NewLimiter(10, 50) // 每秒10个令牌，最多容纳50个

func handler(w http.ResponseWriter, r *http.Request) {
    if !limiter.Allow() {
        http.Error(w, "Too Many Requests", http.StatusTooManyRequests)
        return
    }
    w.Write([]byte("OK"))
}

func main() {
    http.HandleFunc("/", handler)
    http.ListenAndServe(":8080", nil)
}

var clients = make(map[string]*rate.Limiter)
var mtx sync.Mutex

func getLimiter(ip string) *rate.Limiter {
    mtx.Lock()
    defer mtx.Unlock()

    limiter, exists := clients[ip]
    if !exists {
        limiter = rate.NewLimiter(2, 5) // 每秒2次，最多5次突发
        clients[ip] = limiter
    }
    return limiter
}

func limitedHandler(w http.ResponseWriter, r *http.Request) {
    ip := r.RemoteAddr
    if !getLimiter(ip).Allow() {
        http.Error(w, "Rate limit exceeded", http.StatusTooManyRequests)
        return
    }
    w.Write([]byte("Hello"))
}

func rateLimit(next http.HandlerFunc) http.HandlerFunc {
    return func(w http.ResponseWriter, r *http.Request) {
        ip := r.RemoteAddr
        limiter := getLimiter(ip)

        if !limiter.Allow() {
            http.Error(w, "Too many requests", http.StatusTooManyRequests)
            return
        }
        next(w, r)
    }
}

// 使用
http.HandleFunc("/api/data", rateLimit(dataHandler))

import "github.com/go-redis/redis/v8"

rdb := redis.NewClient(&redis.Options{Addr: "localhost:6379"})
limiter := redis_rate.NewLimiter(rdb)
limiter.Allow(ctx, "ip:"+ip, redis_rate.PerSecond(5))