Node InSim

An InSim library for Node.js with TypeScript support.

Introduction

Node InSim provides a JavaScript API to communicate with the Live for Speed InSim protocol over a TCP connection. After connecting to an LFS host via a hostname and a port, you are able to send InSim packets to the host and receive incoming packets from the host.

All packet structures in Node InSim are identical to the structs defined in the InSim protocol. All packet classes with all their properties are documented according to the specification.

InSim compatibility

Node InSim is compatible with InSim version 9.

Installation

Install the node-insim NPM package in your Node.js application:

npm install --save node-insim

or if you use Yarn:

yarn add node-insim

Documentation

For more detailed documentation of the public API, see https://simbroadcasts.github.io/node-insim/.

Usage

Connecting

To connect to an LFS host, you must enter its hostname, a port and a short name of your InSim application.

The InSim port must be configured in the LFS host settings. Also, make sure the public IP address from which your application is connecting is allowed to connect to the host's InSim port.

Single host

import { InSim } from 'node-insim';

const inSim = new InSim();

inSim.connect({
  Host: '127.0.0.1',
  Port: 29999,
  IName: 'Node InSim App',
});

Multiple hosts

To connect to multiple hosts at once, create a new InSim instance for each host.

import { InSim } from 'node-insim';

const inSim1 = new InSim();

inSim1.connect({
  Host: '127.0.0.1',
  Port: 29999,
  IName: 'Node InSim App',
});

const inSim2 = new InSim();

inSim2.connect({
  Host: '127.0.0.2',
  Port: 30000,
  IName: 'Node InSim App',
});

TCP / UDP

By default, Node InSim opens a TCP connection. If you want to use UDP, set the Protocol option to UDP in the connect function.

import { InSim } from 'node-insim';

const inSim = new InSim();

inSim.connect({
  Host: '127.0.0.1',
  Port: 29999,
  IName: 'Node InSim App',
  Protocol: 'UDP',
});

Sending packets

InSim packets can be sent using the send() method on the InSim class instance, which takes a single argument - the packet class instance.

A fast way to set packet properties is to populate them in the class constructor:

import { InSim } from 'node-insim';
import { IS_TINY, TinyType } from 'node-insim/packets';

const inSim = new InSim();

inSim.connect({
  Host: '127.0.0.1',
  Port: 29999,
  IName: 'Node InSim App',
});

inSim.send(
  new IS_TINY({
    ReqI: 1,
    SubT: TinyType.TINY_PING,
  }),
);

Another way is to assign each property after creating the instance:

import { InSim } from 'node-insim';
import { IS_TINY, TinyType } from 'node-insim/packets';

const inSim = new InSim();

inSim.connect({
  Host: '127.0.0.1',
  Port: 29999,
  IName: 'Node InSim App',
});

const pingPacket = new IS_TINY();
pingPacket.ReqI = 1;
pingPacket.SubT = TinyType.TINY_PING;

inSim.send(pingPacket);

Receiving packets

The InSim class exposes an on() method, which is used to listen for incoming packets by their type.

import { InSim } from 'node-insim';
import type { IS_VER } from 'node-insim/packets';
import { PacketType } from 'node-insim/packets';

const inSim = new InSim();

inSim.on(PacketType.ISP_VER, onVersion);

function onVersion(packet: IS_VER) {
  console.log(`Connected to LFS ${packet.product} ${packet.Version}`);
}

The event callback contains the received packet, and an optional second argument - the InSim instance which received that packet. You can use that instance to send additional packets in response.

import { InSim } from 'node-insim';
import { PacketType } from 'node-insim/packets';
import type { IS_VER } from 'node-insim/packets';

const inSim = new InSim();

inSim.on(PacketType.ISP_VER, onVersion);

function onVersion(packet: IS_VER, inSim: InSim) {
  inSim.send(
    new IS_TINY({
      ReqI: 1,
      SubT: TinyType.TINY_PING,
    }),
  );
}

Multiple hosts

You can use the inSim argument in the event handler callback to identify the source host of the received packets, for instance by the options.Host property.

Alternatively, the InSim class constructor accepts an optional id argument, which can also be used to tell apart the InSim connections.

import { InSim } from 'node-insim';

const inSim1 = new InSim('Host One');

inSim1.connect({
  Host: '127.0.0.1',
  Port: 29999,
  IName: 'Node InSim App',
});

const inSim2 = new InSim('Host Two');

inSim2.connect({
  Host: '127.0.0.2',
  Port: 30000,
  IName: 'Node InSim App',
});

inSim.on(PacketType.ISP_VER, onVersion);

function onVersion(packet: IS_VER, inSim: InSim) {
  console.log(`Connected to ${inSim.options.Host}:${inSim.options.Port}`);

  if (inSim.id) {
    console.log(`InSim connection ID: ${inSim.id}`);
  }
}

String encoding

All strings in received or sent packets are automatically converted from LFS encoding to Unicode and vice versa.

If you need to access the raw LFS-encoded string in a received packet, use the _raw property in the packet instance, which contains all unconverted string properties.

import { InSim } from 'node-insim';
import { PacketType } from 'node-insim/packets';
import type { IS_ISM } from 'node-insim/packets';

const inSim = new InSim();

inSim.on(PacketType.ISP_ISM, (packet: IS_ISM) => {
  console.log(packet.HName); // UTF-8 string - ^1Drifter Team ^7★ Server
  console.log(packet._raw.HName); // raw string - ^1Drifter Team ^7^J�� Server\u0000\u0000\u0000\u0000
});

When you send a Unicode string value in a packet, each character will get encoded into the correct LFS encoding, so LFS can display the text in a message or a button.

import { InSim } from 'node-insim';
import { PacketType } from 'node-insim/packets';
import type { IS_MSL } from 'node-insim/packets';

const inSim = new InSim();

inSim.on(PacketType.ISP_VER, (packet: IS_VER) => {
  inSim.send(
    new IS_MSL({
      Msg: 'čau světe', // LFS will receive: ^Eèau svìte
    }),
  );
});

InSim Relay

To connect to the InSim Relay service, use the connectRelay() method. Once connected, you can send and receive relay packets. The following example demonstrates how to show a list of hosts connected to the InSim Relay:

import { InSim } from 'node-insim';
import { IR_HLR, IR_HOS, PacketType, HInfo } from 'node-insim/packets';

inSim.connectRelay();

inSim.on('connect', () => {
  // Request a list of hosts
  inSim.send(new IR_HLR());
});

inSim.on(PacketType.IRP_HOS, (packet: IR_HOS) => {
  // Log the name of each received host
  packet.Info.forEach((host: HInfo) => {
    console.log(host.HName);
  });
});

More information about the InSim Relay protocol can be found in the InSim Relay client information thread on LFS forum.

OutGauge

import { OutGauge, OutGaugePack } from 'node-insim';

const outGauge = new OutGauge();

outGauge.connect({
  Host: '127.0.0.1',
  Port: 29999,
});

outGauge.on('packet', (data: OutGaugePack) => {
  console.clear();
  console.log(data.RPM);
});

OutSim

import { OutSim, OutSimPack } from 'node-insim';

const outSim = new OutSim();

outSim.connect({
  Host: '127.0.0.1',
  Port: 29999,
});

outSim.on('packet', (data) => {
  // Make sure the simple OutSimPack packet is really received, as opposed to OutSimPack2
  if (!(data instanceof OutSimPack)) {
    return;
  }

  console.clear();
  console.log(data.PosX);
});

Debugging

Node InSim uses the debug NPM package for debug logs. By default, Node InSim does not output any logs to the standard output.

To enable logging, use the DEBUG environment variable when running your InSim application. All logs are prefixed with node-insim. You can use wildcards to filter out the logs that you need.

DEBUG=* node insim.js # debug all messages
DEBUG=node-insim:tcp node insim.js # debug only TCP protocol messages

Example applications

You can find example applications using Node InSim in the examples folder.

Example
InSim connection	JavaScript + CJS	TypeScript + ESM
InSim connection (multiple hosts)	JavaScript + CJS	TypeScript + ESM
InSim connection (UDP)	JavaScript + CJS	TypeScript + ESM
InSim Relay	JavaScript + CJS	TypeScript + ESM
OutGauge	JavaScript + CJS	TypeScript + ESM
OutGauge with InSim buttons	JavaScript + CJS	TypeScript + ESM
OutSim	JavaScript + CJS	TypeScript + ESM
OutSim with Options	JavaScript + CJS	TypeScript + ESM

Before you run an example, follow the instructions in each example's README.md file.

For instance, to run the "InSim connection - TypeScript" example, run the following commands:

cd examples/typescript/insim-connection
npm install
npm start

Development

Requirements

• Node.js 18
• Yarn

Start a development server

yarn dev

Code generators

When adding new InSim packets to the library, you can use built-in code generators using yarn generate. It will create and update all the necessary files for you.

Run unit tests

yarn test
yarn test:watch

Run tests against a real LFS application

To run these tests, LFS must be running with an InSim port open.

By default, the tests connect to 127.0.0.1:29999. The InSim host and port can be configured by copying .env to .env.local in the lfs-test directory.

yarn test:lfs

Build all example applications

This command will go through each application in the examples/ folder, install its dependencies, then build the application (typescript only).

yarn test:examples

Lint code

yarn lint

Format code

yarn format

Production build

Compiled files will be created in dist/.

yarn build

Run all checks at once

You can run code format, lint + fix, build and test with the following command:

yarn check-all

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