window

README

Sliding Window Rate Limiter

该包实现了基于滑动窗口的限流算法。

特性

• 将时间窗口分多个桶,根据桶内计数限流

• 滑动窗口,重置统计

• 支持设置窗口和桶的时间大小

• 获取任意时间范围内的请求数

• 简单易用

示例

sw := window.New(10*time.Second, 1*time.Second, 10) 

if !sw.Allow() {
  // 限流逻辑
}

count := sw.Count(5*time.Second) // 最近5秒请求数

接口

• New 创建滑动窗口,传入窗口大小,桶大小和桶数

• Allow 处理请求,检查是否限流

• Count 获取时间范围内请求数

• Reset 重置所有桶的计数

实现原理

• 将时间窗口均分为多个桶

• 每个桶记录一段时间内的请求数

• 滑动窗口,旧桶重置计数

• 汇总多个桶的计数得出时间范围内请求数

优点

• 精确限流时间范围内请求率

• 记录少量数据,内存占用低

• 滑动窗口,限流平滑自然

Documentation

Index

• type SlidingWindow
  • func New(windowSize, bucketSize time.Duration, bucketCount int) (*SlidingWindow, error)
  • func (sw *SlidingWindow) Allow() bool
  • func (sw *SlidingWindow) BucketCount(idx int) int
  • func (sw *SlidingWindow) Count(d time.Duration) int
  • func (sw *SlidingWindow) Reset()

Types

type SlidingWindow

type SlidingWindow struct {
	sync.Mutex
	// contains filtered or unexported fields
}

SlidingWindow implements a fixed-size sliding window for rate limiting.

func New

func New(windowSize, bucketSize time.Duration, bucketCount int) (*SlidingWindow, error)

NewSlidingWindow creates a new sliding window with the given window size, bucket size and bucket count. Window size must be divisible by bucket size.

func (*SlidingWindow) Allow

func (sw *SlidingWindow) Allow() bool

Allow reports whether a new event should be allowed, and if so increments the

func (*SlidingWindow) BucketCount

func (sw *SlidingWindow) BucketCount(idx int) int

BucketCount returns the current count for the given bucket index.

func (*SlidingWindow) Count

func (sw *SlidingWindow) Count(d time.Duration) int

Count returns the total count for the given duration

func (*SlidingWindow) Reset

func (sw *SlidingWindow) Reset()

Reset resets the counts in all buckets to 0.