@technical-1/workers

Web/Service Worker awareness for Puppeteer pages: enumerate workers, evaluate inside a worker, and observe worker lifecycle with typed events and a DI logger.

Convenience wrapper. This package wraps puppeteer-core's page.workers(), WebWorker.evaluate, and the workercreated/workerdestroyed events with typed lifecycle events, typed errors (WorkerError), and a DI logger. It adds no capability beyond those primitives — it exists so worker enumeration, in-worker evaluation, and lifecycle tracking compose through one consistent, typed surface instead of three ad hoc call sites.

import { listWorkers, evaluateInWorker, observeWorkers } from "@technical-1/workers";

// Snapshot the page's currently-live workers:
const workers = listWorkers(page);
console.log(workers.map((w) => w.url));

// Run code inside a worker's realm:
const result = await evaluateInWorker(workers[0].worker, () => self.location.href);

// Track workers spawning/exiting for the page's lifetime:
const observer = observeWorkers(page, {
  onWorkerCreated: (info) => console.log("created", info.url),
  onWorkerDestroyed: (info) => console.log("destroyed", info.url),
  onError: (err) => console.error(err.message),
});

// ... run your flow ...

console.log(observer.created); // readonly WorkerInfo[] currently live
console.log(observer.events);  // readonly WorkerLifecycleEvent[] full history
observer.dispose();            // detach both listeners (idempotent)

Errors

Evaluate failures (e.g. the worker was destroyed mid-evaluate, or the function threw) and consumer-callback failures inside observeWorkers are surfaced as WorkerError from @technical-1/core, discriminated by err.name === "WorkerError", with retryable:true. evaluateInWorker throws it directly; observeWorkers routes it to the onError callback and the injected logger at level error — never thrown from inside the event listener.

v1 limitations

• listWorkers returns a snapshot, not a live view — it does not update as workers spawn/exit (use observeWorkers for lifecycle tracking).
• observeWorkers attaches its own workercreated/workerdestroyed listener pair; multiple concurrent observers on one page all fire (puppeteer allows multiple listeners), so attach one.

Peer

Requires puppeteer-core >=22 <25. It is a type-only peer dependency — it supplies the Page/WebWorker types used at compile time; this package never imports it at runtime.