0.3.2

pkg/rate/rate.go

@@ -0,0 +1,44 @@
+package rate
+
+import (
+    "sync"
+    "time"
+)
+
+type Limiter struct {
+    rate       float64
+    interval   time.Duration
+    lastUpdate time.Time
+    allowance  float64
+    mutex      sync.Mutex
+}
+
+func NewLimiter(rate float64, interval time.Duration) *Limiter {
+    return &Limiter{
+        rate:       rate,
+        interval:   interval,
+        lastUpdate: time.Now(),
+        allowance:  rate,
+    }
+}
+
+func (l *Limiter) Allow() bool {
+    l.mutex.Lock()
+    defer l.mutex.Unlock()
+
+    now := time.Now()
+    elapsed := now.Sub(l.lastUpdate)
+    l.lastUpdate = now
+
+    l.allowance += elapsed.Seconds() * l.rate
+    if l.allowance > l.rate {
+        l.allowance = l.rate
+    }
+
+    if l.allowance < 1.0 {
+        return false
+    }
+
+    l.allowance -= 1.0
+    return true
+}