fix(local): thumbnails oom

drivers/local/driver.go

@@ -30,6 +30,10 @@ type Local struct {
 	model.Storage
 	Addition
 	mkdirPerm int32
+
+	// zero means no limit
+	thumbConcurrency int
+	thumbTokenBucket TokenBucket
 }
 
 func (d *Local) Config() driver.Config {
@@ -62,6 +66,18 @@ func (d *Local) Init(ctx context.Context) error {
 			return err
 		}
 	}
+	if d.ThumbConcurrency != "" {
+		v, err := strconv.ParseUint(d.ThumbConcurrency, 10, 32)
+		if err != nil {
+			return err
+		}
+		d.thumbConcurrency = int(v)
+	}
+	if d.thumbConcurrency == 0 {
+		d.thumbTokenBucket = NewNopTokenBucket()
+	} else {
+		d.thumbTokenBucket = NewStaticTokenBucket(d.thumbConcurrency)
+	}
 	return nil
 }
 
@@ -126,7 +142,6 @@ func (d *Local) FileInfoToObj(f fs.FileInfo, reqPath string, fullPath string) mo
 		},
 	}
 	return &file
-
 }
 func (d *Local) GetMeta(ctx context.Context, path string) (model.Obj, error) {
 	f, err := os.Stat(path)
@@ -178,7 +193,13 @@ func (d *Local) Link(ctx context.Context, file model.Obj, args model.LinkArgs) (
 	fullPath := file.GetPath()
 	var link model.Link
 	if args.Type == "thumb" && utils.Ext(file.GetName()) != "svg" {
-		buf, thumbPath, err := d.getThumb(file)
+		var buf *bytes.Buffer
+		var thumbPath *string
+		err := d.thumbTokenBucket.Do(ctx, func() error {
+			var err error
+			buf, thumbPath, err = d.getThumb(file)
+			return err
+		})
 		if err != nil {
 			return nil, err
 		}

drivers/local/meta.go

@@ -9,6 +9,7 @@ type Addition struct {
 	driver.RootPath
 	Thumbnail        bool   `json:"thumbnail" required:"true" help:"enable thumbnail"`
 	ThumbCacheFolder string `json:"thumb_cache_folder"`
+	ThumbConcurrency string `json:"thumb_concurrency" default:"16" required:"false" help:"Number of concurrent thumbnail generation goroutines. This controls how many thumbnails can be generated in parallel."`
 	ShowHidden       bool   `json:"show_hidden" default:"true" required:"false" help:"show hidden directories and files"`
 	MkdirPerm        string `json:"mkdir_perm" default:"777"`
 	RecycleBinPath   string `json:"recycle_bin_path" default:"delete permanently" help:"path to recycle bin, delete permanently if empty or keep 'delete permanently'"`

drivers/local/token_bucket.go

@@ -0,0 +1,61 @@
+package local
+
+import "context"
+
+type TokenBucket interface {
+	Take() <-chan struct{}
+	Put()
+	Do(context.Context, func() error) error
+}
+
+// StaticTokenBucket is a bucket with a fixed number of tokens,
+// where the retrieval and return of tokens are manually controlled.
+// In the initial state, the bucket is full.
+type StaticTokenBucket struct {
+	bucket chan struct{}
+}
+
+func NewStaticTokenBucket(size int) StaticTokenBucket {
+	bucket := make(chan struct{}, size)
+	for range size {
+		bucket <- struct{}{}
+	}
+	return StaticTokenBucket{bucket: bucket}
+}
+
+func (b StaticTokenBucket) Take() <-chan struct{} {
+	return b.bucket
+}
+
+func (b StaticTokenBucket) Put() {
+	b.bucket <- struct{}{}
+}
+
+func (b StaticTokenBucket) Do(ctx context.Context, f func() error) error {
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-b.bucket:
+		defer b.Put()
+	}
+	return f()
+}
+
+// NopTokenBucket all function calls to this bucket will success immediately
+type NopTokenBucket struct {
+	nop chan struct{}
+}
+
+func NewNopTokenBucket() NopTokenBucket {
+	nop := make(chan struct{})
+	close(nop)
+	return NopTokenBucket{nop}
+}
+
+func (b NopTokenBucket) Take() <-chan struct{} {
+	return b.nop
+}
+
+func (b NopTokenBucket) Put() {}
+
+func (b NopTokenBucket) Do(_ context.Context, f func() error) error { return f() }