msgpack

README

Msgpack implementation for Golang

Supports:

• Primitives, arrays, maps, structs and interface{}.
• time.Time.
• Appengine *datastore.Key and datastore.Cursor.
• Extensions for user defined types.
• Struct field renaming, e.g. msgpack:"my_field_name".
• Omitempty flag, e.g. msgpack:",omitempty".

API docs: http://godoc.org/gopkg.in/vmihailenco/msgpack.v2

Installation

Install:

go get gopkg.in/vmihailenco/msgpack.v2

Usage

Examples:

func ExampleEncode() {
    b, err := msgpack.Marshal(true)
    fmt.Printf("%v %#v\n", err, b)
    // Output: <nil> []byte{0xc3}
}

func ExampleDecode() {
    var out bool
    err := msgpack.Unmarshal([]byte{0xc3}, &out)
    fmt.Println(err, out)
    // Output: <nil> true
}

func ExampleMapStringInterface() {
    in := map[string]interface{}{"foo": 1, "hello": "world"}
    b, err := msgpack.Marshal(in)
    _ = err

    var out map[string]interface{}
    err = msgpack.Unmarshal(b, &out)
    fmt.Printf("%v %#v\n", err, out)
    // Output: <nil> map[string]interface {}{"foo":1, "hello":"world"}
}

func ExampleRecursiveMapStringInterface() {
    buf := &bytes.Buffer{}

    enc := msgpack.NewEncoder(buf)
    in := map[string]interface{}{"foo": map[string]interface{}{"hello": "world"}}
    _ = enc.Encode(in)

    dec := msgpack.NewDecoder(buf)
    dec.DecodeMapFunc = func(d *msgpack.Decoder) (interface{}, error) {
        n, err := d.DecodeMapLen()
        if err != nil {
            return nil, err
        }

        m := make(map[string]interface{}, n)
        for i := 0; i < n; i++ {
            mk, err := d.DecodeString()
            if err != nil {
                return nil, err
            }

            mv, err := d.DecodeInterface()
            if err != nil {
                return nil, err
            }

            m[mk] = mv
        }
        return m, nil
    }
    out, err := dec.DecodeInterface()
    fmt.Printf("%v %#v\n", err, out)
    // Output: <nil> map[string]interface {}{"foo":map[string]interface {}{"hello":"world"}}
}

Extensions

Look at appengine.go for example.

Documentation

Overview

Example (MapStringInterface)

in := map[string]interface{}{"foo": 1, "hello": "world"}
b, err := msgpack.Marshal(in)
_ = err

var out map[string]interface{}
err = msgpack.Unmarshal(b, &out)

var outKeys []string
for k := range out {
	outKeys = append(outKeys, k)
}
sort.Strings(outKeys)

fmt.Printf("err: %v\n", err)

for _, k := range outKeys {
	fmt.Printf("out[\"%v\"]: %#v\n", k, out[k])
}

Output:

err: <nil>
out["foo"]: 1
out["hello"]: "world"

Example (RecursiveMapStringInterface)

buf := &bytes.Buffer{}

enc := msgpack.NewEncoder(buf)
in := map[string]interface{}{"foo": map[string]interface{}{"hello": "world"}}
_ = enc.Encode(in)

dec := msgpack.NewDecoder(buf)
dec.DecodeMapFunc = func(d *msgpack.Decoder) (interface{}, error) {
	n, err := d.DecodeMapLen()
	if err != nil {
		return nil, err
	}

	m := make(map[string]interface{}, n)
	for i := 0; i < n; i++ {
		mk, err := d.DecodeString()
		if err != nil {
			return nil, err
		}

		mv, err := d.DecodeInterface()
		if err != nil {
			return nil, err
		}

		m[mk] = mv
	}
	return m, nil
}
out, err := dec.DecodeInterface()
fmt.Printf("%v %#v\n", err, out)

Output:

<nil> map[string]interface {}{"foo":map[string]interface {}{"hello":"world"}}

Index

• func Marshal(v ...interface{}) ([]byte, error)
• func Register(typ reflect.Type, enc encoderFunc, dec decoderFunc)
• func Unmarshal(b []byte, v ...interface{}) error
• type CustomDecoder
• type CustomEncoder
• type Decoder
  • func NewDecoder(r io.Reader) *Decoder
  • func (d *Decoder) Decode(v ...interface{}) error
  • func (d *Decoder) DecodeBool() (bool, error)
  • func (d *Decoder) DecodeBytes() ([]byte, error)
  • func (d *Decoder) DecodeBytesLen() (int, error)
  • func (d *Decoder) DecodeFloat32() (float32, error)
  • func (d *Decoder) DecodeFloat64() (float64, error)
  • func (d *Decoder) DecodeInt() (int, error)
  • func (d *Decoder) DecodeInt16() (int16, error)
  • func (d *Decoder) DecodeInt32() (int32, error)
  • func (d *Decoder) DecodeInt64() (int64, error)
  • func (d *Decoder) DecodeInt8() (int8, error)
  • func (d *Decoder) DecodeInterface() (interface{}, error)
  • func (d *Decoder) DecodeMap() (interface{}, error)
  • func (d *Decoder) DecodeMapLen() (int, error)
  • func (d *Decoder) DecodeNil() error
  • func (d *Decoder) DecodeSlice() ([]interface{}, error)
  • func (d *Decoder) DecodeSliceLen() (int, error)
  • func (d *Decoder) DecodeString() (string, error)
  • func (d *Decoder) DecodeTime() (time.Time, error)
  • func (d *Decoder) DecodeUint() (uint, error)
  • func (d *Decoder) DecodeUint16() (uint16, error)
  • func (d *Decoder) DecodeUint32() (uint32, error)
  • func (d *Decoder) DecodeUint64() (uint64, error)
  • func (d *Decoder) DecodeUint8() (uint8, error)
  • func (d *Decoder) DecodeValue(v reflect.Value) error
• type Encoder
  • func NewEncoder(w io.Writer) *Encoder
  • func (e *Encoder) Encode(v ...interface{}) error
  • func (e *Encoder) EncodeBool(value bool) error
  • func (e *Encoder) EncodeBytes(v []byte) error
  • func (e *Encoder) EncodeFloat32(n float32) error
  • func (e *Encoder) EncodeFloat64(n float64) error
  • func (e *Encoder) EncodeInt(v int) error
  • func (e *Encoder) EncodeInt16(v int16) error
  • func (e *Encoder) EncodeInt32(v int32) error
  • func (e *Encoder) EncodeInt64(v int64) error
  • func (e *Encoder) EncodeInt8(v int8) error
  • func (e *Encoder) EncodeNil() error
  • func (e *Encoder) EncodeSliceLen(l int) error
  • func (e *Encoder) EncodeString(v string) error
  • func (e *Encoder) EncodeTime(tm time.Time) error
  • func (e *Encoder) EncodeUint(v uint) error
  • func (e *Encoder) EncodeUint16(v uint16) error
  • func (e *Encoder) EncodeUint32(v uint32) error
  • func (e *Encoder) EncodeUint64(v uint64) error
  • func (e *Encoder) EncodeUint8(v uint8) error
  • func (e *Encoder) EncodeValue(v reflect.Value) error
• type Marshaler
• type Unmarshaler

Examples

• Package (MapStringInterface)
• Package (RecursiveMapStringInterface)
• Marshal
• Unmarshal

Functions

func Marshal

func Marshal(v ...interface{}) ([]byte, error)

Example

b, err := msgpack.Marshal(true)
fmt.Printf("%v %#v\n", err, b)

Output:

<nil> []byte{0xc3}

func Register

func Register(typ reflect.Type, enc encoderFunc, dec decoderFunc)

func Unmarshal

func Unmarshal(b []byte, v ...interface{}) error

Example

var out bool
err := msgpack.Unmarshal([]byte{0xc3}, &out)
fmt.Println(err, out)

Output:

<nil> true

Types

type CustomDecoder

type CustomDecoder interface {
	DecodeMsgpack(*Decoder) error
}

type CustomEncoder

type CustomEncoder interface {
	EncodeMsgpack(*Encoder) error
}

type Decoder

type Decoder struct {
	DecodeMapFunc func(*Decoder) (interface{}, error)
	// contains filtered or unexported fields
}

func NewDecoder

func NewDecoder(r io.Reader) *Decoder

func (*Decoder) Decode

func (d *Decoder) Decode(v ...interface{}) error

func (*Decoder) DecodeBool

func (d *Decoder) DecodeBool() (bool, error)

func (*Decoder) DecodeBytes

func (d *Decoder) DecodeBytes() ([]byte, error)

func (*Decoder) DecodeBytesLen

func (d *Decoder) DecodeBytesLen() (int, error)

func (*Decoder) DecodeFloat32

func (d *Decoder) DecodeFloat32() (float32, error)

func (*Decoder) DecodeFloat64

func (d *Decoder) DecodeFloat64() (float64, error)

func (*Decoder) DecodeInt

func (d *Decoder) DecodeInt() (int, error)

func (*Decoder) DecodeInt16

func (d *Decoder) DecodeInt16() (int16, error)

func (*Decoder) DecodeInt32

func (d *Decoder) DecodeInt32() (int32, error)

func (*Decoder) DecodeInt64

func (d *Decoder) DecodeInt64() (int64, error)

func (*Decoder) DecodeInt8

func (d *Decoder) DecodeInt8() (int8, error)

func (*Decoder) DecodeInterface

func (d *Decoder) DecodeInterface() (interface{}, error)

Decodes value into interface. Possible value types are:

• nil,
• int64,
• uint64,
• bool,
• float32 and float64,
• string,
• slices of any of the above,
• maps of any of the above.

func (*Decoder) DecodeMap

func (d *Decoder) DecodeMap() (interface{}, error)

func (*Decoder) DecodeMapLen

func (d *Decoder) DecodeMapLen() (int, error)

func (*Decoder) DecodeNil

func (d *Decoder) DecodeNil() error

func (*Decoder) DecodeSlice

func (d *Decoder) DecodeSlice() ([]interface{}, error)

func (*Decoder) DecodeSliceLen

func (d *Decoder) DecodeSliceLen() (int, error)

func (*Decoder) DecodeString

func (d *Decoder) DecodeString() (string, error)

func (*Decoder) DecodeTime

func (d *Decoder) DecodeTime() (time.Time, error)

func (*Decoder) DecodeUint

func (d *Decoder) DecodeUint() (uint, error)

func (*Decoder) DecodeUint16

func (d *Decoder) DecodeUint16() (uint16, error)

func (*Decoder) DecodeUint32

func (d *Decoder) DecodeUint32() (uint32, error)

func (*Decoder) DecodeUint64

func (d *Decoder) DecodeUint64() (uint64, error)

func (*Decoder) DecodeUint8

func (d *Decoder) DecodeUint8() (uint8, error)

func (*Decoder) DecodeValue

func (d *Decoder) DecodeValue(v reflect.Value) error

type Encoder

type Encoder struct {
	// contains filtered or unexported fields
}

func NewEncoder

func NewEncoder(w io.Writer) *Encoder

func (*Encoder) Encode

func (e *Encoder) Encode(v ...interface{}) error

func (*Encoder) EncodeBool

func (e *Encoder) EncodeBool(value bool) error

func (*Encoder) EncodeBytes

func (e *Encoder) EncodeBytes(v []byte) error

func (*Encoder) EncodeFloat32

func (e *Encoder) EncodeFloat32(n float32) error

func (*Encoder) EncodeFloat64

func (e *Encoder) EncodeFloat64(n float64) error

func (*Encoder) EncodeInt

func (e *Encoder) EncodeInt(v int) error

func (*Encoder) EncodeInt16

func (e *Encoder) EncodeInt16(v int16) error

func (*Encoder) EncodeInt32

func (e *Encoder) EncodeInt32(v int32) error

func (*Encoder) EncodeInt64

func (e *Encoder) EncodeInt64(v int64) error

func (*Encoder) EncodeInt8

func (e *Encoder) EncodeInt8(v int8) error

func (*Encoder) EncodeNil

func (e *Encoder) EncodeNil() error

func (*Encoder) EncodeSliceLen

func (e *Encoder) EncodeSliceLen(l int) error

func (*Encoder) EncodeString

func (e *Encoder) EncodeString(v string) error

func (*Encoder) EncodeTime

func (e *Encoder) EncodeTime(tm time.Time) error

func (*Encoder) EncodeUint

func (e *Encoder) EncodeUint(v uint) error

func (*Encoder) EncodeUint16

func (e *Encoder) EncodeUint16(v uint16) error

func (*Encoder) EncodeUint32

func (e *Encoder) EncodeUint32(v uint32) error

func (*Encoder) EncodeUint64

func (e *Encoder) EncodeUint64(v uint64) error

func (*Encoder) EncodeUint8

func (e *Encoder) EncodeUint8(v uint8) error

func (*Encoder) EncodeValue

func (e *Encoder) EncodeValue(v reflect.Value) error

type Marshaler

type Marshaler interface {
	MarshalMsgpack() ([]byte, error)
}

Deprecated. Use CustomEncoder.

type Unmarshaler

type Unmarshaler interface {
	UnmarshalMsgpack([]byte) error
}

Deprecated. Use CustomDecoder.