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Streaming with events() ​

Problem ​

Implement streaming with events() in a production-friendly way with @vielzeug/eventit while keeping setup and cleanup explicit.

Runnable Example ​

The snippet below is copy-paste runnable in a TypeScript project with @vielzeug/eventit installed.

Process an ongoing sequence of events as an async generator:

ts
async function watchCart() {
  const controller = new AbortController();

  // Stop streaming after 30 seconds of inactivity (extend pattern)
  let timeout = setTimeout(() => controller.abort(), 30_000);

  for await (const { items, total } of appBus.events('cart:updated', controller.signal)) {
    clearTimeout(timeout);
    timeout = setTimeout(() => controller.abort(), 30_000);
    renderCart(items, total);
  }
}

Expected Output ​

  • The example runs without type errors in a standard TypeScript setup.
  • The main flow produces the behavior described in the recipe title.

Common Pitfalls ​

  • Forgetting cleanup/dispose calls can leak listeners or stale state.
  • Skipping explicit typing can hide integration issues until runtime.
  • Not handling error branches makes examples harder to adapt safely.