Events can be processed out of order

[debdutdeb]

It seems like we can get into an out of order insertion of events into the in-memory queue.

The event is processed synchronously - https://github.com/matrix-org/matrix-appservice-node/blob/20b8fdc0f2c6acfd71638bc1d12fef0666b9cd6d/src/app-service.ts#L294

But bridge uses async callbacks, that can cause the actual insertion to defer.

for eeEventBroker -

matrix-appservice-bridge/src/bridge.ts

Lines 741 to 742 in 0998090

	if (this.eeEventBroker) {
	passthrough = await this.eeEventBroker.onASEvent(weakEvent);

, enqueued here.

another possibility -

matrix-appservice-bridge/src/bridge.ts

Lines 1337 to 1338 in 0998090

	// Event rejected.
	if (!await this.validateEditEvent(event, relatesTo.event_id, editOptions.allowEventOnLookupFail)) {

Am I missing some context while reading the code? Could someone please clarify?