Add: thumb quality for 3rd storage policy (#1763)

Add thumb quality for third party storage policy.

pkg/filesystem/driver/cos/handler.go

@@ -234,9 +234,12 @@ func (handler Driver) Thumb(ctx context.Context, file *model.File) (*response.Co
 		ok        = false
 	)
 	if thumbSize, ok = ctx.Value(fsctx.ThumbSizeCtx).([2]uint); !ok {
-		return nil, errors.New("无法获取缩略图尺寸设置")
+		return nil, errors.New("failed to get thumbnail size")
 	}
-	thumbParam := fmt.Sprintf("imageMogr2/thumbnail/%dx%d", thumbSize[0], thumbSize[1])
+
+	thumbEncodeQuality := model.GetIntSetting("thumb_encode_quality", 85)
+
+	thumbParam := fmt.Sprintf("imageMogr2/thumbnail/%dx%d/quality/%d", thumbSize[0], thumbSize[1], thumbEncodeQuality)
 
 	source, err := handler.signSourceURL(
 		ctx,