codec

type BaseSession struct {
	ReqHead interface{}
	RspHead interface{}
}

type Codec interface {
	// codec name
	Name() string

	// Encode encode 'pkg' into []byte, here 'pkg' must be []byte,
	// which is marshaled and compressed data.
	Encode(pkg interface{}) (data []byte, err error)

	// Decode decode []byte, return decoded body data and length,
	// which is marshaled and compressed data.
	Decode(data []byte) (req interface{}, n int, err error)
}

type CompressType int

type Compressor interface {
	// compress data
	Compress(data []byte) ([]byte, error)
	// decomress data
	Decompress(data []byte) ([]byte, error)
}

type GZipCompressor struct{}

type MarshalType int

type Marshaler interface {
	// Marshal serializes 'pkg' to []byte, return the data,
	// return error if any error encountered.
	Marshal(pkg interface{}) (data []byte, err error)

	// Unmarhshal deserializes []byte to pkg, which must be a pointer,
	// return error if any error encountered.
	Unmarshal(data []byte, pkg interface{}) error
}

type PBMarshaler struct{}

type Session interface {
	RPCName() string

	Request() interface{}

	Response() interface{}

	SetResponse(rsp interface{})

	SetError(err error)
}

type SessionBuilder interface {
	Build(reqHead interface{}) (Session, error)
}