80 lines
1.3 KiB
Go
80 lines
1.3 KiB
Go
package middleware
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import (
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"net/http"
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"sync"
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"time"
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"github.com/gin-gonic/gin"
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)
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type RateLimiter struct {
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visitors map[string]*Visitor
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mu sync.Mutex
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}
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type Visitor struct {
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lastSeen time.Time
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tokens int
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}
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func NewRateLimiter() *RateLimiter {
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rl := &RateLimiter{
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visitors: make(map[string]*Visitor),
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}
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// 定期清理过期访问者
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go rl.cleanupVisitors()
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return rl
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}
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func (rl *RateLimiter) cleanupVisitors() {
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for {
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time.Sleep(time.Minute)
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rl.mu.Lock()
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for ip, v := range rl.visitors {
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if time.Since(v.lastSeen) > time.Minute {
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delete(rl.visitors, ip)
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}
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}
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rl.mu.Unlock()
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}
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}
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func (rl *RateLimiter) LimitMiddleware(maxRequests int, per time.Duration) gin.HandlerFunc {
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return func(c *gin.Context) {
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ip := c.ClientIP()
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rl.mu.Lock()
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defer rl.mu.Unlock()
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v, exists := rl.visitors[ip]
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if !exists {
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rl.visitors[ip] = &Visitor{
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lastSeen: time.Now(),
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tokens: maxRequests - 1,
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}
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c.Next()
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return
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}
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// 重置 token
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if time.Since(v.lastSeen) > per {
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v.tokens = maxRequests - 1
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v.lastSeen = time.Now()
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c.Next()
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return
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}
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if v.tokens > 0 {
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v.tokens--
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v.lastSeen = time.Now()
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c.Next()
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return
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}
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// 超过限流
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c.AbortWithStatusJSON(http.StatusTooManyRequests, gin.H{
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"error": "请求过于频繁,请稍后再试",
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})
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}
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}
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