Installation

nmp i @rtf-dm/protocol

Simple and small package to describe packets

Usage:

import { Packet, encode, decode, Schema } from '@rtf-dm/protocol';

//1. Describe your packet payload type:

type TestPacketPayload = {
  ID: string;
  numberField1b: number;
  numberField2b: number;
  numberField4b: number;
  numberField2bBE: number;
  numberField4bBE: number;
  arrayField1b: number[];
  arrayField2bLe: number[];
  arrayField2bBe: number[];
  filler: number;
  filler2: number;
  arrayField4bLe: number[];
  arrayField4bBe: number[];
};

/*2. Describe encoding schema:
 *    Note that order of schema fields make sense!
 *    It means if 'ID' field first in array and have a length 5
 *    first five bytes in packet will have value of 'ID' payload;
 * */

const schema = new Schema<TestPacketPayload>([
  ['ID', { size: 1, length: 5, type: 'string', encoding: 'ascii' }],
  ['numberField1b', { size: 1, type: 'number' }],
  ['numberField2b', { size: 2, type: 'number', byteOrder: 'LE' }],
  ['numberField4b', { size: 4, type: 'number', byteOrder: 'LE' }],
  ['numberField2bBE', { size: 2, type: 'number', byteOrder: 'BE' }],
  ['numberField4bBE', { size: 4, type: 'number', byteOrder: 'BE' }],
  ['arrayField1b', { length: 4, type: 'array', size: 1 }],
  ['arrayField2bLe', { length: 4, type: 'array', size: 2, byteOrder: 'LE' }],
  ['arrayField2bBe', { length: 4, type: 'array', size: 2, byteOrder: 'BE' }],
  ['filler', { size: 1, type: 'number' }],
  ['filler2', { size: 1, type: 'number' }],
  ['arrayField4bBe', { length: 4, type: 'array', size: 4, byteOrder: 'BE' }],
  ['arrayField4bLe', { length: 4, type: 'array', size: 4, byteOrder: 'LE' }],
]);

//3. Create a new class that extends Packet class:
class TestPacket extends Packet<TestPacketPayload> {
  constructor(payload: TestPacketPayload) {
    super(payload, schema);
  }
}

const packet = new TestPacket({
  ID: 'TEST',
  numberField1b: 1,
  numberField2b: 1024,
  numberField4b: 123456,
  numberField2bBE: 0xffdd,
  numberField4bBE: 0xaabbccdd,
  arrayField1b: [0xfa, 0xfa, 0xfa, 0xfa],
  arrayField2bLe: [0xfffe, 0xfffe, 0xfffe, 0xfffe],
  arrayField2bBe: [0xfffe, 0xfffe, 0xfffe, 0xfffe],
  filler: 129, // align to
  filler2: 138,
  arrayField4bLe: [0xfafbfcfd, 0xfafbfcfd, 0xfafbfcfd, 0xfafbfcfd],
  arrayField4bBe: [0xfafbfcfd, 0xfafbfcfd, 0xfafbfcfd, 0xfafbfcfd],
});

const buf = packet.encode();
const decoded = packet.decode(buf);

VER 0.6.3

• Update readme

VER 0.6.1

• Rename schema "length" field for non array type to "size" for consistency
• Types improvements

VER 0.5.12

• Fixed types.
• Added support for array encoding
• Added support for strings encoding ('utf8' and 'ascii' was tested other encodings not planned to be tested)
• Test coverage: 100% at that moment