# README

MessagePack encoding for Golang

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Resources

Features

Primitives, arrays, maps, structs, time.Time and interface{}.
Appengine *datastore.Key and datastore.Cursor.
CustomEncoder/CustomDecoder interfaces for custom encoding.
Extensions to encode type information.
Renaming fields via msgpack:"my_field_name" and alias via msgpack:"alias:another_name".
Omitting individual empty fields via msgpack:",omitempty" tag or all empty fields in a struct.
Map keys sorting.
Encoding/decoding all structs as arrays or individual structs.
Encoder.SetCustomStructTag with Decoder.SetCustomStructTag can turn msgpack into drop-in replacement for any tag.
Simple but very fast and efficient queries.

Installation

msgpack supports 2 last Go versions and requires support for Go modules. So make sure to initialize a Go module:

go mod init github.com/my/repo

And then install msgpack/v5 (note v5 in the import; omitting it is a popular mistake):

go get github.com/vmihailenco/msgpack/v5

Quickstart

import "github.com/vmihailenco/msgpack/v5"

func ExampleMarshal() {
    type Item struct {
        Foo string
    }

    b, err := msgpack.Marshal(&Item{Foo: "bar"})
    if err != nil {
        panic(err)
    }

    var item Item
    err = msgpack.Unmarshal(b, &item)
    if err != nil {
        panic(err)
    }
    fmt.Println(item.Foo)
    // Output: bar
}