feat: configuration

internal/pkg/filesystem/cache.go

@@ -0,0 +1,70 @@
+package filesystem
+
+import (
+	"context"
+	"log/slog"
+	"sync/atomic"
+	"time"
+
+	"github.com/valkey-io/valkey-go"
+)
+
+const keyStat = "webdav:stat:"
+
+// CachedClient wraps a FileSystem implementation with Valkey caching.
+type CachedClient struct {
+	impl        FS
+	cache       valkey.Client
+	ttl         time.Duration
+	hits        atomic.Int64
+	misses      atomic.Int64
+	readDirHits atomic.Int64
+	readHits    atomic.Int64
+}
+
+// NewCachedClient creates a new CachedClient.
+func NewCachedClient(impl FS, client valkey.Client, refreshtime time.Duration) *CachedClient {
+	c := &CachedClient{
+		impl:  impl,
+		cache: client,
+		ttl:   refreshtime * 5,
+	}
+
+	go func() {
+		t := time.NewTicker(refreshtime)
+		for {
+			<-t.C
+			c.revalidate(context.Background())
+		}
+	}()
+
+	return c
+}
+
+func (c *CachedClient) revalidate(ctx context.Context) {
+	go c.revalidateReadDir(ctx)
+	go c.revalidateRead(ctx)
+	go c.revalidateStat(ctx)
+}
+
+func (c *CachedClient) scanAndProcess(ctx context.Context, match string, process func(key string) error) {
+	cursor := uint64(0)
+	for {
+		res, err := c.cache.Do(ctx, c.cache.B().Scan().Cursor(cursor).Match(match).Build()).AsScanEntry()
+		if err != nil {
+			slog.Error("scan failed", "match", match, "err", err)
+			return
+		}
+
+		for _, key := range res.Elements {
+			if err := process(key); err != nil {
+				slog.Debug("process failed", "key", key, "err", err)
+			}
+		}
+
+		cursor = res.Cursor
+		if cursor == 0 {
+			break
+		}
+	}
+}