accordant
v0.3.4
Published
One way shared/worker async bindings
Maintainers
webreflectionReadme
accordant
One way shared/worker async bindings to simply export bindings, as callbacks, from a Worker or a SharedWorker's port.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width,initial-scale=1.0">
<script type="module">
import { SharedWorker, Worker, broadcast, proxied } from 'accordant/main';
const sw = new SharedWorker('./shared-worker.js', {
// invoked per each broadcast (except its own one)
[broadcast](...args) {
console.log('SharedWorker', ...args);
}
});
const w = new Worker('./worker.js', {
// invoked per each broadcast (from the worker.js only)
[broadcast](...args) {
console.log('Worker', ...args);
}
});
// both workers export a `random` method
console.log(await sw.random());
console.log(await w.random());
console.log(proxied(sw)); // MessagePort
console.log(proxied(w)); // Worker
// broadcast any data to other ports (but not sw)
sw[broadcast](1, 2, 3);
</script>
</head>
</html>// shared-worker.js - multiple ports
import { broadcast, exports } from 'accordant/shared-worker';
const sameValue = Math.random();
exports({
random: () => ({ SharedWorker: sameValue }),
});
let ports = 0;
// using the broadcast utility to notify all ports
addEventListener('port:connected', () => {
broadcast('connected ports', ++ports);
});
addEventListener('port:disconnected', () => {
broadcast('disconnected port, now there are', --ports, 'ports');
});// worker.js - single "port"
import { broadcast, exports } from 'accordant/worker';
exports({
random: () => ({ Worker: Math.random() }),
});
// just invoke the broadcast symbol option
broadcast('current', 'worker');broadcast
This module offers the current possibilities:
- on the main thread, it is possible to import the
broadcastsymbol to help avoiding conflicts with both exported functions (because symbols cannot survive a postMessage dance) and SharedWorker or Worker options (future proof, no name clashing). This function will be triggered when the counter SharedWorker or Worker code decides, arbitrarily, to reflect that invoke on each main thread/port, passing along any serializable argument - on the SharedWorker or Worker thread, it is possible to import the
broadcastfunction, so that a call such asbroadcast(...args)within the worker context will invoke, if defined, the main thread callback optionally passed during instantiation. In here it is a function because polluting the global worker context with a symbol didn't feel like the right thing to do
// main thread
const sw = new SharedWorker('./shared-worker.js', {
[broadcast](...args) {
// invoked when shared-worker.js calls broadcast(...args)
}
});
const w = new Worker('./worker.js', {
[broadcast](...args) {
// invoked when worker.js calls broadcast(...args)
}
});Still on the main thread, it is also possible to sw[broadcast](...args) so that all other ports still listening or available on the Shared Worker side of affairs will receive those serialized args.
Please note that for feature parity it is also possible to w[broadcast](...args) but this does practically nothing because a worker cannot have multiple ports attached so it will silently send data to nothing but it allow code to be portable across platforms and browsers' versions.