subscribersFor method
The subscribers this hub would relay producerEndpointId's stream to.
Read-only, and the only way to tell a route that was actually torn down
from one a client is merely ignoring locally — which is exactly the
distinction NetworkStream.removeInlet has to get right.
Implementation
Set<String> subscribersFor({
required String streamName,
required String producerEndpointId,
}) => _routing.subscribersFor(
streamName: streamName,
producerEndpointId: producerEndpointId,
);