Feat: file download in service level

pkg/filesystem/errors.go

@@ -1,6 +1,9 @@
 package filesystem
 
-import "errors"
+import (
+	"errors"
+	"github.com/HFO4/cloudreve/pkg/serializer"
+)
 
 var (
 	ErrUnknownPolicyType       = errors.New("未知存储策略类型")
@@ -8,7 +11,8 @@ var (
 	ErrFileExtensionNotAllowed = errors.New("不允许上传此类型的文件")
 	ErrInsufficientCapacity    = errors.New("容量空间不足")
 	ErrIllegalObjectName       = errors.New("目标名称非法")
-	ErrInsertFileRecord        = errors.New("无法插入文件记录")
+	ErrInsertFileRecord        = serializer.NewError(serializer.CodeDBError, "无法插入文件记录", nil)
 	ErrFileExisted             = errors.New("同名文件已存在")
-	ErrPathNotExist            = errors.New("路径不存在")
+	ErrPathNotExist            = serializer.NewError(404, "路径不存在", nil)
+	ErrObjectNotExist          = serializer.NewError(404, "文件不存在", nil)
 )