ESBuild + Watch + Reload in Node.js

README.md

ESBuild + Watch + Reload in Node.js

Iterate on a module locally, and dynamically assemble it with ESBuild.

Especially useful with npm link but can also work on arbitrary entrypoints.

webvision.ts

import { watch } from 'node:fs';
import { fileURLToPath } from 'node:url';

import { build, } from 'esbuild';

let webvisionBundle = await buildBundle();

const webvisionEntrypoint = fileURLToPath(import.meta.resolve('@athree/webvision'));
const watchTarget = webvisionEntrypoint.replace('out/main/index.js', 'out');

watch(watchTarget, {
    recursive: true,
}, async () => {
    webvisionBundle = await buildBundle();
});

export function getWebvisionModule() {
    return webvisionBundle.outputFiles[0].text;
}

export function getWebvisionUrl() {
    const webvisionModule = getWebvisionModule();
    return `data:text/javascript;base64,${Buffer.from(webvisionModule).toString('base64')}`;
}

async function buildBundle() {
    return await build({
        entryPoints: ['@athree/webvision'],
        format: 'esm',
        write: false,
        bundle: true,
        minify: true,
        keepNames: true,
        logLevel: 'info'
    });
}