@zedtech/zedkit-live

Framework-free live data sources for the browser and Node 22+: one small LiveSource interface, a pollingSource, and a wsSource that reconnects and can fall back to polling while the socket is down. No React, no DOM beyond the global WebSocket (overridable).

See CATALOG.md for exports and examples.

Install

pnpm add @zedtech/zedkit-live

Use

import { pollingSource, wsSource } from "@zedtech/zedkit-live";

const source = wsSource<{ id: string }>({
  url: "wss://example.com/live",
  fallback: pollingSource({ intervalMs: 10_000, poll: () => fetchLatest() }),
});

const stop = source.subscribe((message) => refresh(message));
source.onStatus((status) => console.log(status)); // connecting | live | retrying | idle
stop();

A source starts on its first subscriber and stops on its last unsubscribe. getStatus plus onStatus fit useSyncExternalStore or any store:

const status = useSyncExternalStore(source.onStatus, source.getStatus, () => "idle");

Behavior to know

• Messages missed while the socket was down are not replayed. Make the fallback fetch current state.
• Status only moves while at least one message listener is subscribed; subscribing to status alone starts nothing.
• status describes the primary transport: retrying stays while a fallback delivers messages.
• A throwing listener does not affect other listeners; errors go to onError.

Original work

Original work by the same author.