Add initial cut of auto expiry of objects

pkg/fs/auto-expiry.go

@@ -0,0 +1,41 @@
+package fs
+
+import (
+	"os"
+	"time"
+)
+
+// AutoExpiryThread - auto expiry thread
+func (fs Filesystem) AutoExpiryThread(expiry time.Duration) {
+	expireFiles := func(fp string, fl os.FileInfo, err error) error {
+		if fp == fs.path {
+			return nil
+		}
+		if fl.Mode().IsRegular() || fl.Mode()&os.ModeSymlink == os.ModeSymlink {
+			if time.Now().Sub(fl.ModTime()) > expiry {
+				if err := os.Remove(fp); err != nil {
+					if os.IsNotExist(err) {
+						return nil
+					}
+					return err
+				}
+			}
+			return ErrDirNotEmpty
+		}
+		return nil
+	}
+	ticker := time.NewTicker(3 * time.Hour)
+	for {
+		select {
+		// TODO - add a way to stop the timer thread
+		case <-ticker.C:
+			err := WalkUnsorted(fs.path, expireFiles)
+			if err != nil {
+				if !os.IsNotExist(err) && err != ErrDirNotEmpty {
+					ticker.Stop()
+					return
+				}
+			}
+		}
+	}
+}