Web Worker driven Classes and methods

Andrea Giammarchi
May 22, 2018 · 4 min read

He dropped 95% of a bundle size with a simple trick

self.addEventListener('message', event => {
switch(event.data.cmd) {
case 'initializeApp': ...
case 'firestore.col.add': ...
case 'firestore.col.onSnapshot': ...

workway: a general purpose Web Worker exporter

a @jonathan_klok walkway picture from @unsplash
// file /worker.js
// import anything else needed and initialize firestorm// expose remotely the following namespace
// either as object or Promise that will resolve one
utils: {
random: (size = 8) => String.fromCharCode(
...crypto.getRandomValues(new Uint8Array(size))
app: {
User: class User {
constructor() {
this.uid = firebase.auth().currentUser.uid;
getName() {
return firebase.database()
.ref('/users/' + this.uid)
.then(snapshot => ((
snapshot.val() && snapshot.val().username
) || 'Anonymous'));
// generic message listeners (addEventListener works too)
self.onmessage = event => console.log(event.data);
// file /bundle.js for the main thread
workway('/worker.js').then(async ({worker, namespace}) => {
const user = new namespace.app.User;
user.getName().then(name => {
worker.postMessage(`Thanks from ${name}!`);
const rand = await namespace.utils.random(16);

Offload as much as possible for a cost of 0.5K !

Key features

As Summary

Andrea Giammarchi

Written by

Web, Mobile, IoT, and all JS things since 00's. Formerly JS engineer at @nokia, @facebook, @twitter.

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