msgpack

msgpack-go

msgpack-go is a MessagePack implementation for the Go programming language.

Encoding

To encode values into the binary MessagePack format, an Encode function is provided:

func Encode(w io.Writer, v Encoder) error

Encoder describes an encodable type which fulfills the interface

type Encoder interface {
	EncodeMsgpack(w *Writer) error
}

and writes its value to the given writer. The Writer type provides a Write* method for each supported data type. For a complete overview of the Writer type, see the documentation.

Decoding

To decode binary MessagePack data into values, a Decode function is provided:

func Decode(r io.Reader, v Decoder) error

Decoder describes a decodable type which fulfills the interface

type Decoder interface {
	DecodeMsgpack(r *Reader) error
}

and reads the necessary values from the given reader. The Reader type provides a Read* method for each supported data type. Furthermore, a reader provides the following extra methods:

• Peek for looking up the next type in the stream without moving the read pointer, and
• Skip for skipping any value which comes next in the stream.

For a complete overview of the Reader type, see the documentation.

Example

package main

import (
	"bytes"
	"log"

	msgpack "github.com/mprot/msgpack-go"
)

type Custom struct {
	Number  int
	Boolean bool
}

func (c *Custom) EncodeMsgpack(w *msgpack.Writer) error {
	if err := w.WriteInt(c.Number); err != nil {
		return err
	}
	return w.WriteBool(c.Boolean)
}

func (c *Custom) DecodeMsgpack(r *msgpack.Reader) (err error) {
	if c.Number, err = r.ReadInt(); err != nil {
		return err
	}
	c.Boolean, err = r.ReadBool()
	return err
}

func main() {
	var buf bytes.Buffer

	encoded := &Custom{Number: 7, Boolean: true}
	if err := msgpack.Encode(&buf, encoded); err != nil {
		log.Fatal(err)
	}

	decoded := &Custom{}
	if err := msgpack.Decode(&buf, decoded); err != nil {
		log.Fatal(err)
	}

	if decoded.Number != encoded.Number || decoded.Boolean != encoded.Boolean {
		log.Fatal("something went wrong")
	}
}