精简后的项目：仅保留 api/ui 源码、文档、构建依赖

api/utils/media_cache.go

@@ -0,0 +1,73 @@
+package utils
+
+import (
+	"os"
+	"path"
+	"strconv"
+	"sync"
+
+	"github.com/pkg/errors"
+)
+
+// CachePathForMedia is a low-level implementation for Media.CachePath()
+func CachePathForMedia(albumID int, mediaID int) (string, error) {
+
+	// Make root cache dir if not exists
+	if _, err := os.Stat(MediaCachePath()); os.IsNotExist(err) {
+		if err := os.Mkdir(MediaCachePath(), os.ModePerm); err != nil {
+			return "", errors.Wrap(err, "could not make root image cache directory")
+		}
+	}
+
+	// Make album cache dir if not exists
+	albumCachePath := path.Join(MediaCachePath(), strconv.Itoa(int(albumID)))
+	if _, err := os.Stat(albumCachePath); os.IsNotExist(err) {
+		if err := os.Mkdir(albumCachePath, os.ModePerm); err != nil {
+			return "", errors.Wrap(err, "could not make album image cache directory")
+		}
+	}
+
+	// Make photo cache dir if not exists
+	photoCachePath := path.Join(albumCachePath, strconv.Itoa(int(mediaID)))
+	if _, err := os.Stat(photoCachePath); os.IsNotExist(err) {
+		if err := os.Mkdir(photoCachePath, os.ModePerm); err != nil {
+			return "", errors.Wrap(err, "could not make photo image cache directory")
+		}
+	}
+
+	return photoCachePath, nil
+}
+
+var (
+	testCachePath       string = ""
+	testCachePathLocker sync.RWMutex
+)
+
+func GetTestCachePath() string {
+	testCachePathLocker.RLock()
+	defer testCachePathLocker.RUnlock()
+	return testCachePath
+}
+
+func ConfigureTestCache(tmpDir string) {
+	testCachePathLocker.Lock()
+	defer testCachePathLocker.Unlock()
+	testCachePath = tmpDir
+}
+
+// MediaCachePath returns the path for where the media cache is located on the file system
+func MediaCachePath() string {
+	testCachePathLocker.RLock()
+	cachedPath := testCachePath
+	testCachePathLocker.RUnlock()
+	if cachedPath != "" {
+		return cachedPath
+	}
+
+	photoCache := EnvMediaCachePath.GetValue()
+	if photoCache == "" {
+		photoCache = "./media_cache"
+	}
+
+	return photoCache
+}