Without engine broadcasts or Echo, a board polls. No setup is needed: it is on by default, so every board converges on the latest state within realtime.poll_interval seconds.
How a poll works
Each poll calls the board's poll() action. The server compares a fingerprint of each column's cards with the previous poll, in one query, and:
- returns nothing when nothing changed, so an idle board costs one small request per interval;
- returns just the columns whose cards changed (a card joined, left, moved within the column, or its order was updated), which the page morphs in place;
- asks for a full board render when the board's setup changed (a column added, removed, reordered, or edited, or an automation badge changed).
Polls only read, so they don't count against the board's rate limit, however short the interval.
When it pauses
A board skips a poll while:
- a card is being dragged;
- a move is still in flight;
- the browser tab is hidden;
- the browser is offline.
It polls at once when the tab is shown again.
Tuning
// config/artisanpack/ecommerce-kanban-livewire.php
'realtime' => [
'enabled' => true,
'poll_interval' => 15, // seconds; 0 turns polling off
],
A shorter interval shows other people's changes sooner, at the cost of one request per open board per interval. With poll_interval at 0 and no Echo, the header says "Not updating automatically" and the board only changes on reload. realtime.enabled at false turns off both polling and Echo.
Polling is also the fallback for live boards: when the Echo connection drops, the board polls until it reconnects. See Broadcasting with Echo.