encodr

Encodr

Encoding/Decoding to/from CBOR/MsgPack/JSON for Node.js and Browser.

About

This is a small JavaScript abstraction layer for Node.js and the Browser to encode/decode JavaScript values to/from the (binary) object serialization formats Concise Binary Object Representation (CBOR, RFC7049), MessagePack (MsgPack) and JavaScript Object Notation (JSON, RFC4627). The actual encoding/decoding is performed by underyling libraries. This package is just a convenient abstraction layer to ensure the correct library and consistent data types are used.

Installation

$ npm install encodr

Usage

import Encodr from "encodr"

const CBOR    = new Encodr("cbor")
const MSGPACK = new Encodr("msgpack")
const JSON    = new Encodr("json")

let data = {
    foo: "bar",
    baz: 42,
    baz: [ 1.0, "quux", true ],
    quux: {}
}

data = CBOR.encode(data)
data = CBOR.decode(data)

data = MSGPACK.encode(data)
data = MSGPACK.decode(data)

data = JSON.encode(data)
data = JSON.decode(data)

Application Programming Interface

• type BLOB = Buffer | Uint8Array
  The BLOB data type depends on the execution environment: In Node.js it is Buffer, in the Browsers it is Uint8Array.

• new Encodr(format: string = "cbor"): Encodr
  Create a new Encodr instance for a particular encoding format. The supported formats are cbor, msgpack, json and jsons. The default is cbor.

• Encodr::encode(data: any): BLOB
  Encode a JavaScript value to the serialization format.

• Encodr::decode(data: BLOB): any
  Decode a JavaScript value from the serialization format.

Encoding Formats

The following regular serialization formats are supported:

• cbor: Concise Binary Object Representation (CBOR, RFC7049):
  This is a very compact, efficient and IETF-standardized serialization format.

• msgpack: MessagePack (MsgPack):
  This is a very compact, efficient and battle-tested serialization format.

For convenience and application development reasons, there is also an additional special serialization format:

• json: UTF-16 string-encoded JavaScript Object Notation (JSON, RFC4627):
  This is a less compact, less efficient but IETF-standardized and human-readable serialization format.

  This serialization format is JSON encoded into a regular UTF-16 character string (instead of the UTF-8 byte array as it is the case for cbor and msgpack) and hence the API BLOB type here becomes String as an unregular case.

  This serialization format exists for development purposes only, where one wants to easily switch the encoding to a human-readable string representation. For instance, when transferring the data over WebSockets via WebSocket-Framed, the resulting WebSocket frame will be human-readable in the Browser's debugger.

License

Copyright (c) 2017-2021 Dr. Ralf S. Engelschall (http://engelschall.com/)

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.