Solo Rails #3: Front-end stack config.

bun.config.js

import path from 'path';
import fs from 'fs';

const config = {
  sourcemap: "external",
  entrypoints: ["app/javascript/application.js"],
  outdir: path.join(process.cwd(), "app/assets/builds"),
  minify: true,
};

const build = async (config) => {
  const result = await Bun.build(config);

  if (!result.success) {
    if (process.argv.includes('--watch')) {
      console.error("Build failed");
      for (const message of result.logs) {
        console.error(message);
      }
      return;
    } else {
      throw new AggregateError(result.logs, "Build failed");
    }
  }
};

(async () => {
  await build(config);

  if (process.argv.includes('--watch')) {
    fs.watch(path.join(process.cwd(), "app/javascript"), { recursive: true }, (eventType, filename) => {
      console.log(`File changed: ${filename}. Rebuilding...`);
      build(config);
    });
  } else {
    process.exit(0);
  }
})();

package.json

{
  "name": "app",
  "private": "true",
  "dependencies": {
  },
  "devDependencies": {
  },
  "scripts": {
    "build:css": "postcss ./app/assets/stylesheets/application.postcss.css -o ./app/assets/builds/application.css",
    "build": "bun bun.config.js",
    "outdated": "bunx npm-check-updates"
  }
}

Procfile.dev

web: bin/rails server -p 3000
css: bun run build:css --watch
js: bun run build --watch
jobs: bundle exec good_job start