Rust, Neon, Electron

Electron running native Rust code is a very appealing idea: we get a decent cross-platform user interface with all the performance of native Rust underneath it, and the convenience of Node.js in the middle.

Neon is a really useful project that permits us to write native Rust modules that work with Node.js.

I wanted to create a working example, particularly one that works on Windows as well as Linux. It doesn't really do anything useful, but rather serves as a barebones working example for my own reference. It's a bit of fiddling to get working correctly the first time.

• This repo is forked from https://github.com/electron/electron-quick-start
• I have added to it following the instructions on the Neon site: https://neon-bindings.com/docs/electron-apps/

Testing

• npm i installs the dependencies
• npm run build runs native Rust builds targeting Electron specifically
• npm start starts the app

Details

For a coder not familiar with npm or Node, there are some things to be aware of:

• Node integration needs to be enabled in main.js: nodeIntegration: true
• Neon bindings are not currently context aware or NAPI, so there are deprecation warnings. I'd expect this to improve at some point.
• I had to comment out <meta http-equiv="Content-Security-Policy" content="default-src 'self'; script-src 'self'"> to enable Electron to run the native packages; there might be a better way to do this.

On the Rust side,

• Don't despair; the Rust build only takes a while on the first run. Incremental builds after changes are quick.
• npm i installs the dependencies,
  • Our local hello package is configured to build correctly on installation:
    • package.json contains "install": "electron-build-env neon build --release"
• The main build script is in the root packages.js
• npm run build will do the Rust build of the native libraries
  • Local hello is already correctly built as noted above, but this will re-build it if there are changes
  • Imported @amilajack/neon-hello is not correctly built, as it is built for Node without Electron; the build call here re-builds it targeting electron; it's not an electron-specific example: https://github.com/amilajack/neon-hello
  • electron-build-env sets up the correct environment variables to target Electron, rather than normal Node
  • neon build -p {path} --release uses neon-cli to run the Rust build; Note that it needs to be --release on Windows
• Local hello was created using neon-cli by doing neon new hello
  • on Windows, it's a build dependency, so accessible in node_modules\.bin\neon
  • hello was modified to export the native module with module.exports = require('../native'); in hello/lib/index.js

Tooling

This project is working on Windows 10 and Ubuntu 20.04 with the following tooling:

• Rust 1.43 (stable)
• npm 6.14.4
• Visual Studio 2019 Community Edition, with MSVC v142 (v14.25) installed (only on Windows of course)

Original template

Based on this: https://github.com/electron/electron-quick-start; I've left the original documentation below. Refer to the original repo for updates.

electron-quick-start

Clone and run for a quick way to see Electron in action.

This is a minimal Electron application based on the Quick Start Guide within the Electron documentation.

Use this app along with the Electron API Demos app for API code examples to help you get started.

A basic Electron application needs just these files:

• package.json - Points to the app's main file and lists its details and dependencies.
• main.js - Starts the app and creates a browser window to render HTML. This is the app's main process.
• index.html - A web page to render. This is the app's renderer process.

You can learn more about each of these components within the Quick Start Guide.

To Use

To clone and run this repository you'll need Git and Node.js (which comes with npm) installed on your computer. From your command line:

# Clone this repository
git clone https://github.com/electron/electron-quick-start
# Go into the repository
cd electron-quick-start
# Install dependencies
npm install
# Run the app
npm start

Note: If you're using Linux Bash for Windows, see this guide or use node from the command prompt.

Resources for Learning Electron

• electronjs.org/docs - all of Electron's documentation
• electronjs.org/community#boilerplates - sample starter apps created by the community
• electron/electron-quick-start - a very basic starter Electron app
• electron/simple-samples - small applications with ideas for taking them further
• electron/electron-api-demos - an Electron app that teaches you how to use Electron
• hokein/electron-sample-apps - small demo apps for the various Electron APIs

License

CC0 1.0 (Public Domain)