@serve-tools/client-event-source

@serve-tools/client-event-source adds typed JSON events to the native EventSource API while preserving browser-managed reconnection and event IDs.

import { connect } from "@serve-tools/client-event-source";

using events = connect<{
	message: { text: string };
	presence: { online: number };
}>("https://example.com/events", { withCredentials: true });

using presence = events.subscribe("presence", ({ data, lastEventId }) => {
	console.log(lastEventId, data.online);
});

Install

npm install @serve-tools/client-event-source

Each event's data field is parsed with JSON.parse, so event values are restricted to JSON-compatible types. The callback also receives the native event type, origin, and lastEventId used by EventSource reconnection.

The underlying native instance is available as client.source for open, error, readyState, url, and withCredentials. Malformed JSON is reported through the client platform's global reportError() and does not replace the browser's native reconnection behavior. Closing the client or aborting its lifetime signal closes the native EventSource.

Use @serve-tools/server-event-source to produce the matching text/event-stream response.

Agent Skill

The package includes an Agent Skill at skills/serve-tools-client-event-source.

License

MIT-0