feat: initial release

internal/app/storage.go

@@ -0,0 +1,50 @@
+package app
+
+import (
+	"context"
+	"math"
+	"os"
+	"path/filepath"
+	"time"
+)
+
+func (app *App) StartCleanupTask(ctx context.Context) {
+	ticker := time.NewTicker(1 * time.Hour)
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-ticker.C:
+			app.CleanDir(app.Conf.StorageDir, false)
+			app.CleanDir(filepath.Join(app.Conf.StorageDir, "tmp"), true)
+		}
+	}
+}
+
+func (app *App) CleanDir(path string, isTmp bool) {
+	entries, _ := os.ReadDir(path)
+	for _, entry := range entries {
+		info, _ := entry.Info()
+		expiry := 4 * time.Hour
+		if !isTmp {
+			expiry = CalculateRetention(info.Size(), app.Conf.MaxMB)
+		}
+
+		if time.Since(info.ModTime()) > expiry {
+			os.RemoveAll(filepath.Join(path, entry.Name()))
+		}
+	}
+}
+
+func CalculateRetention(fileSize int64, maxMB int64) time.Duration {
+	const (
+		minAge = 24 * time.Hour
+		maxAge = 365 * 24 * time.Hour
+	)
+	ratio := math.Max(0, math.Min(1, float64(fileSize)/float64(maxMB<<20)))
+	retention := float64(maxAge) * math.Pow(1.0-ratio, 3)
+	if retention < float64(minAge) {
+		return minAge
+	}
+	return time.Duration(retention)
+}