From c1987237d05adcce77c614e5247a181ae5cdfacd Mon Sep 17 00:00:00 2001
From: Oleg Lobanov <oleg@lobanov.me>
Date: Mon, 21 Feb 2022 19:59:22 +0100
Subject: [PATCH] feat: use real image path to calculate cache key

---
 files/file.go    | 13 +++++++++++++
 http/preview.go  |  8 ++++----
 http/resource.go |  2 +-
 3 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/files/file.go b/files/file.go
index 36852f39..569b0be4 100644
--- a/files/file.go
+++ b/files/file.go
@@ -185,6 +185,19 @@ func (i *FileInfo) Checksum(algo string) error {
 	return nil
 }
 
+func (i *FileInfo) RealPath() string {
+	if realPathFs, ok := i.Fs.(interface {
+		RealPath(name string) (fPath string, err error)
+	}); ok {
+		realPath, err := realPathFs.RealPath(i.Path)
+		if err == nil {
+			return realPath
+		}
+	}
+
+	return i.Path
+}
+
 //nolint:goconst
 //TODO: use constants
 func (i *FileInfo) detectType(modify, saveContent, readHeader bool) error {
diff --git a/http/preview.go b/http/preview.go
index 9860af91..163d7e49 100644
--- a/http/preview.go
+++ b/http/preview.go
@@ -91,7 +91,7 @@ func handleImagePreview(
 		return errToStatus(err), err
 	}
 
-	cacheKey := previewCacheKey(file.Path, file.ModTime.Unix(), previewSize)
+	cacheKey := previewCacheKey(file, previewSize)
 	resizedImage, ok, err := fileCache.Load(r.Context(), cacheKey)
 	if err != nil {
 		return errToStatus(err), err
@@ -142,7 +142,7 @@ func createPreview(imgSvc ImgService, fileCache FileCache,
 	}
 
 	go func() {
-		cacheKey := previewCacheKey(file.Path, file.ModTime.Unix(), previewSize)
+		cacheKey := previewCacheKey(file, previewSize)
 		if err := fileCache.Store(context.Background(), cacheKey, buf.Bytes()); err != nil {
 			fmt.Printf("failed to cache resized image: %v", err)
 		}
@@ -151,6 +151,6 @@ func createPreview(imgSvc ImgService, fileCache FileCache,
 	return buf.Bytes(), nil
 }
 
-func previewCacheKey(fPath string, fTime int64, previewSize PreviewSize) string {
-	return fmt.Sprintf("%x%x%x", fPath, fTime, previewSize)
+func previewCacheKey(f *files.FileInfo, previewSize PreviewSize) string {
+	return fmt.Sprintf("%x%x%x", f.RealPath(), f.ModTime.Unix(), previewSize)
 }
diff --git a/http/resource.go b/http/resource.go
index ea4fbc29..9264f268 100644
--- a/http/resource.go
+++ b/http/resource.go
@@ -283,7 +283,7 @@ func writeFile(fs afero.Fs, dst string, in io.Reader) (os.FileInfo, error) {
 func delThumbs(ctx context.Context, fileCache FileCache, file *files.FileInfo) error {
 	for _, previewSizeName := range PreviewSizeNames() {
 		size, _ := ParsePreviewSize(previewSizeName)
-		if err := fileCache.Delete(ctx, previewCacheKey(file.Path, file.ModTime.Unix(), size)); err != nil {
+		if err := fileCache.Delete(ctx, previewCacheKey(file, size)); err != nil {
 			return err
 		}
 	}