json2msgpack

This is implementation of generic JSON serialiser to MessagePack in Golang

It complements MessagePack message generator

The problem it solves

MessagePack message generator does not support JSON --> messagePack conversion. It allows JSON iteroperability by just providing data memory to JSON conversion but not backward (see msgp.CopyToJSON() and msgp.UnmarshalAsJSON()) In some cases you do not need message generator for each and every message type you use in your project but rather translation your JSON data to MessagePack. It is useful in your project MessagePack API testing

How to use it

package main

import (
  "fmt"
  json2msgpack "github.com/izinin/json2msgpack"
)

func main(){
  res := json2msgpack.EncodeJSON([]byte(`{"compact":true,"schema":[{"name": "igor"}, {"fname": "zinin"}]}`))
  fmt.Printf("MessagePack format: %#x", test)
}

it outputs MessagePack representation: 0x82a7636f6d70616374c3a6736368656d619281a46e616d65a469676f7281a5666e616d65a57a696e696e

How to test

You run Golang test by command line go test -v

MessagePack data conversion for the test criterias are taken from MessagePack console, Try! menu item

MessagePack message generator interoperability

You should see in debug output two JSON strings original and double converted. Note in dictionary type fields order is not guaranteed(see WTF chapter below)

import (
	"bytes"
	"fmt"

  json2msgpack "github.com/izinin/json2msgpack"
	"github.com/tinylib/msgp/msgp"
)

func main(){
  origStr := `{"compact":true,"schema":[{"name": "igor"}, {"fname": "zinin"}]}`
  src := bytes.NewBuffer([]byte(json2msgpack.EncodeJSON([]byte(origStr)))) 
  var js bytes.Buffer
  _, err := msgp.CopyToJSON(&js, src)
  if err != nil {
  	panic(fmt.Sprintf("Cannot convert MessagePack to JSON: %v", err))
  }
  fmt.Printf("Original JSON: \n\t%s", origStr)
  fmt.Printf("Converted string JSON --> MsgPack --> JSON: \n\t%s", js.String())
}

Golang WTF limitation

Please note JSON unmarshalling does not keep dictionary order, then we use dictionary sorted by key in alphabetical order just to be deterministic. Here is the line.