storage

type BasicStorage interface {
	// Save saves a piece of `Data`
	Save(key string, value io.Reader) (string, error)

	// Load loads a piece of `Data`
	Load(key string, index string) (io.ReadCloser, error)

	// Exist checks existence of a piece of `Data`
	Exist(key string, index string) (bool, error)

	// Delete deletes a piece of `Data`
	Delete(key string, index string) error

	// Update updates a piece of `Data`
	Update(key string, index string, value io.Reader) (string, error)
}

type Storage interface {
	BasicStorage

	//LoadStr loads a piece of `Data`, and convert it to a string
	LoadStr(key string, index string) (string, error)
}