API reference > @kontsedal/olas-realtime > createRealtimePatcher

createRealtimePatcher() function

Subscribe to channel for the lifetime of the surrounding controller and dispatch each event to the matching handler by event.type. Wrapper around the recurring SPEC §16.5 "realtime → cache patches" pattern.

channel is a name or a signal of one. With a signal, a new name unsubscribes from the old channel and subscribes to the new one, so a per-route room is computed(() => 'room:' + params.value.roomId).

Handlers run inside untracked(...) so accidental signal reads (e.g.query.setData((prev) => prev.value)) don't add deps to the enclosing effect, which would otherwise re-subscribe whenever those signals change.

A '*' wildcard handler is invoked for every event, regardless of whether a specific handler matched. Specific handlers run first; the wildcard sees the same event afterwards (in the same untracked scope).

Signature:

export declare function createRealtimePatcher<TEvent extends {
  type: string;
}>(ctx: Ctx<RealtimeDeps>, channel: string | ReadSignal<string>, handlers: PatcherHandlers<TEvent>): void;

Parameters

Parameter	Type	Description
ctx	Ctx<RealtimeDeps>
channel	string | ReadSignal<string>
handlers	PatcherHandlers<TEvent>

Returns:

void