42 lines
978 B
Go
42 lines
978 B
Go
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package ratelimit
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import (
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"context"
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"net/http"
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"time"
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"github.com/gin-gonic/gin"
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"go.uber.org/ratelimit"
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)
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var rl = ratelimit.New(20, ratelimit.WithoutSlack)
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func RateLimitMiddleware() gin.HandlerFunc {
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return func(c *gin.Context) {
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// 1. 给请求设置超时(如3秒,超过3秒未拿到令牌直接返回)
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ctx, cancel := context.WithTimeout(c.Request.Context(), 3*time.Second)
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defer cancel()
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// 2. 用带超时的方式获取令牌(需自定义限流器的 Take 逻辑)
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ch := make(chan struct{}, 1)
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go func() {
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rl.Take() // 阻塞拿令牌
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ch <- struct{}{} // 拿到令牌后通知主协程
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}()
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select {
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case <-ch:
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// 3. 拿到令牌,继续执行
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c.Next()
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case <-ctx.Done():
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// 4. 超时未拿到令牌,返回请求频繁
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c.JSON(http.StatusTooManyRequests, gin.H{
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"code": 429,
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"message": "请求过于频繁,请稍后重试",
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"reason": "等待令牌超时",
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})
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c.Abort()
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}
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}
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}
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