Quickstart: Rate-limit your own widget's API

2 min read

debounceOne quote per pause

coalesceShare in-flight calls

cacheReads served locally

Coalesce duplicate requests

const inflight = new Map();
function dedupe(key, fn) {
  if (inflight.has(key)) return inflight.get(key);
  const promise = fn().finally(() => inflight.delete(key));
  inflight.set(key, promise);
  return promise;
}
// two components asking for products share one call
dedupe('products', () => fetch(`${BASE}/products`).then(r => r.json()));

Debounce and cache

Debounce the quote calls so a slider fires once per pause, and cache the catalogue so multiple widgets on a page share one fetch. Together these keep even a heavy page comfortably under the limit.

Frequently asked questions

Can one page trip the rate limit?

A naive widget with a live slider can. Debounce writes, cache reads and coalesce duplicate in-flight requests and you will stay well within the limit.

What is request coalescing?

When two parts of the page ask for the same data at once, you make one request and share the promise, rather than firing two identical calls.