feat: initial commit

internal/ratelimiter/fixed_window.go

@@ -0,0 +1,51 @@
+package ratelimiter
+
+import (
+	"log"
+	"sync"
+	"time"
+)
+
+type FixedWindowLimiter struct {
+	sync.RWMutex
+	clients map[string]int
+	limit   int
+	window  time.Duration
+}
+
+func NewFixedWindowLimiter(limit int, window time.Duration) *FixedWindowLimiter {
+	return &FixedWindowLimiter{
+		clients: make(map[string]int),
+		limit:   limit,
+		window:  window,
+	}
+}
+
+func (rl *FixedWindowLimiter) Allow(ip string) (bool, time.Duration) {
+	rl.RLock()
+	count, exists := rl.clients[ip]
+	rl.RUnlock()
+
+	log.Println(count, exists)
+
+	if !exists || count < rl.limit {
+		rl.Lock()
+		if !exists {
+			go rl.resetCount(ip)
+		}
+
+		rl.clients[ip]++
+		rl.Unlock()
+		return true, 0
+	}
+
+	return false, rl.window
+}
+
+func (rl *FixedWindowLimiter) resetCount(ip string) {
+	time.Sleep(rl.window)
+
+	rl.Lock()
+	delete(rl.clients, ip)
+	rl.Unlock()
+}