Building from Source

The brs-engine project follows pretty standard Node.js development patterns, being built with Webpack and TypeScript in a monorepo structure with three packages: packages/browser (brs-engine), packages/node (brs-node) and packages/scenegraph (brs-scenegraph).

Prerequisites

As it builds (and runs the CLI) in Node.js (v22 or newer), so you'll need to install that first.

Setup

1. Clone this repo, including the submodules:

   $ git clone --recurse-submodules https://github.com/lvcabral/brs-engine
   

   If you cloned without --recurse-submodules, populate the Roku reference documentation submodule with:

   $ npm run docs:update
   

2. Install dependencies:

   $ npm install
   

The build-test-clean dance

Build

This project is written in TypeScript, so it needs to be compiled before it can be executed. npm run build compiles both packages, using the source code in src/, into JavaScript and TypeScript declarations, and puts them in lib/, bin/ and types/.

$ npm run build

$ ls packages/browser/lib/
brs-sg.js
brs.api.js
brs.worker.js

$ ls packages/node/bin/
brs-sg.node.js
brs.cli.js
brs.ecp.js
brs.node.js

$ ls packages/scenegraph/lib/
brs-sg.js
brs-sg.node.js

$ ls packages/browser/types/
index.d.ts (and friends)

Individual packages can also be built on their own:

Command	Builds
npm run build:api	brs-engine only (browser API + worker)
npm run build:node	brs-node only (CLI, ECP and Node.js library)
npm run build:sg	brs-scenegraph only
npm run build:cli	brs-node followed by brs-scenegraph
npm run build:web	brs-engine + brs-scenegraph, then opens the example web app

Release

To release a smaller version of the libraries Webpack can create a minified version by running npm run release.

Running the Example Web Application

To build and start the web application on your default browser just execute npm run build:web.

Testing

Tests are written in plain-old JavaScript with Vitest, and can be run with the test target:

$ npm run test

If you need to update the snapshots use the command: npx vitest run --update

Cleaning

Compiled output in lib/, bin/ and types/ can be removed with the clean target:

$ npm run clean

$ ls packages/browser/lib/
ls: cannot access 'lib': No such file or directory

$ ls packages/browser/types/
ls: cannot access 'types': No such file or directory

$ ls packages/node/bin/
ls: cannot access 'bin': No such file or directory

$ ls packages/node/types/
ls: cannot access 'types': No such file or directory