core.medplumclient.getmastersubscriptionemitter
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MedplumClient.getMasterSubscriptionEmitter() method
Get the master SubscriptionEmitter for the SubscriptionManager.
The master SubscriptionEmitter gets messages for all subscribed criteria as well as WebSocket errors, connect and disconnect events, and the close event.
It can also be used to listen for heartbeat messages.
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Signature:
getMasterSubscriptionEmitter(): SubscriptionEmitter;
Returns:
the master SubscriptionEmitter from the SubscriptionManager.
Example
### Listening for heartbeat:
const masterEmitter = medplum.getMasterSubscriptionEmitter();
masterEmitter.addEventListener('heartbeat', (bundle: Bundle<SubscriptionStatus>) => {
console.log(bundle?.entry?.[0]?.resource); // A `SubscriptionStatus` of type `heartbeat`
});