fix: multiple Advertisements without network #13
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Add a simple example that fails when run without a network, for example with Docker. See the file for an example on how to execute it.
tkurki
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Handle errors from dsnsd Advertisements and use a version of dnssd that does not throw out of band errors. Once or if DeMille/dnssd.js#13 or something equivalent makes it to npm we should go back to the upstream version of dnssd.
tkurki
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Sep 1, 2019
Handle errors from dsnsd Advertisements and use a version of dnssd that does not throw out of band errors. Once or if DeMille/dnssd.js#13 or something equivalent makes it to npm we should go back to the upstream version of dnssd.
tkurki
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Sep 8, 2019
Handle errors from dsnsd Advertisements and use a version of dnssd that does not throw out of band errors. Once or if DeMille/dnssd.js#13 or something equivalent makes it to npm we should go back to the upstream version of dnssd.
Ignore errors from NetworkInterface, when there are no listeners. Without this multiple Advertisements on a host with no network fails when NetworkInterface emits errors after the first emitted error has already stopped the interface, but there are pending errors from the socket.
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Dnssd fails with
if you create multiple Advertisements on a host with no network available. As far I can tell the reason for this is that the Advertisements share one NetworkInterface, that is shut down when the first Advertisement fails, but there are outstanding that nobody is listening to.
Just adding error handlers to Advertisements do not catch the secondary errors, so somebody using dnssd has no way to guard against this condition.
The PR includes a simple way to demonstrate this with Docker.
I am not familiar enough with dnssd if the fix I included is the way to go. If you have a better way forward please let me know.
My motivation for using dnssd is to be able to work without mdns's native dependencies and possible separate Avahi installation. The original problem that I am solving is that this fails on setups with no internet connection, eg. no gateway and 224.0.0.251:5353 throws ENETUNREACH - the docker incantation is just an easier way to reproduce the issue.