Client events

Browsers on a private or presence channel can send each other events directly, with no request to your server: typing indicators, cursors, live drawing.

const board = rt.subscribe( 'presence-board-1' );

board.on( 'client-typing', ( data, { user_id } ) => showTyping( user_id, data.on ) );

let typed = 0;
input.addEventListener( 'input', () => {
	if ( Date.now() - typed > 2000 ) {
		typed = Date.now();
		board.trigger( 'client-typing', { on: true } ).catch( ( e ) => console.warn( e.code ) );
	}
} );

• Names start with client-. Any other is refused with bad_event.
• Only on private and presence channels the tab has subscribed to. A public channel's are refused with forbidden, since anyone could listen and send.
• Everyone else on the channel gets it, the sender's other tabs included, but not the tab that sent it.
• user_id names the sender: the user the channel's token names, on a presence channel. Your server never sees client events, so treat them as what any member could send.
• Up to 10 a second a browser and 10 KB each. Past it, trigger() rejects with rate_limited or too_large.

trigger() returns a promise that resolves once the server has passed the event on, or rejects with an error whose code says why (errors).