msgpack5

A msgpack v5 implementation for node.js and the browser, with extension points

msgpack5  

A msgpack v5 implementation for node.js and the browser, with extension point support.

npm install msgpack5 --save
var msgpack = require('msgpack5')() // namespace our extensions 
  , a       = new MyType(2, 'a')
  , encode  = msgpack.encode
  , decode  = msgpack.decode
 
msgpack.register(0x42, MyType, mytipeEncode, mytipeDecode)
 
console.log(encode({ 'hello': 'world' }).toString('hex'))
// 81a568656c6c6fa5776f726c64 
console.log(decode(encode({ 'hello': 'world' })))
// { hello: 'world' } 
console.log(encode(a).toString('hex'))
// d5426161 
console.log(decode(encode(a)) instanceof MyType)
// true 
console.log(decode(encode(a)))
// { value: 'a', size: 2 } 
 
function MyType(sizevalue) {
  this.value = value
  this.size  = size
}
 
function mytipeEncode(obj) {
  var buf = new Buffer(obj.size)
  buf.fill(obj.value)
  return buf
}
 
function mytipeDecode(data) {
  var result = new MyType(data.length, data.toString('utf8', 0, 1))
    , i
 
  for (= 0; i < data.length; i++) {
    if (data.readUInt8(0) != data.readUInt8(i)) {
      throw new Error('should all be the same')
    }
  }
 
  return result
}

This library is compatible with Browserify.

If you want to use standalone, grab the file in the dist folder of this repo, and use in your own HTML page, the module will expose a msgpack5 global.

<script type="text/javascript"
        src="./msgpack5.min.js">
</script>
    npm run build


Creates a new instance on which you can register new types for being encoded.

options:

  • forceFloat64, a boolean to that forces all floats to be encoded as 64-bits floats. Defaults is false.

Encodes object in msgpack, returns a bl.


Decodes buf from in msgpack. buf can be a Buffer or a bl instance.

In order to support a stream interface, a user must pass in a bl instance.


Register a new custom object type for being automatically encoded. The arguments are:

  • check, a function that will be called to check if the passed object should be encoded with the encode function
  • encode, a function that will be called to encode an object in binary form; this function must return a Buffer which include the same type for registerDecoder.

Register a new custom objet type for being automatically decoded. The arguments are:

  • type, is a greater than zero integer identificating the type once serialized
  • decode, a function that will be called to decode the object from the passed Buffer

Register a new custom objet type for being automatically encoded and decoded. The arguments are:

  • type, is a greater than zero integer identificating the type once serialized
  • constructor, the function that will be used to match the objects with instanceof
  • encode, a function that will be called to encode an object in binary form; this function must return a Buffer that can be deserialized by the decode function
  • decode, a function that will be called to decode the object from the passed Buffer

This is just a commodity that calls registerEncoder and registerDecoder internally.


Builds a stream in object mode that encodes msgpack.


Builds a stream in object mode that decodes msgpack.

msgpack5 can be used as a LevelUp valueEncoding straight away:

var level = require('level')
  , pack  = msgpack()
  , db    = level('foo', {
      valueEncoding: pack
    })
  , obj   = { my: 'obj' }
 
db.put('hello', obj, function(err) {
  db.get('hello', function(errresult) {
    console.log(result)
    db.close()
  })
})
 

This library is built fully on JS and on bl to simplify the code. Every improvement that keeps the same API is welcome.

This project was kindly sponsored by nearForm.

This library was originally built as the data format for JSChan.

MIT