MdnsSd

Description

Simple Elixir MDNS-SD implementation. Client listens for new services, and notifies any subscribed processes of their presence. Address records and services can be added to Server, which will then respond to requests for the corresponding A, PTR, SRV, and TXT records.

Currently a barebones implementation which does not implement known answer suppression or keep track of TTLs.

Usage

Server

Mdns.Server.add_service({service_instance, service}, service)

where {service_instance, service} is something like {'ff339870', '_onenet-pgn._tcp'} and service is a hash such as:

%{
  port: 3000
  txt: %{
    'nmea-name' => 'foo'
  }
}

Client

Mdns.Client.listen(service_type)

where service_type is something like '_onenet-info._tcp'. This subscribes the calling process to an Informant topic for that service type. When any instance of that service type is announced/updated, the calling process receives a message:

{:informant, MdnsSd, {'_onenet-info._tcp', 'foobar'}, {:changes, %MdnsSd.Service{
  domain: 'johnnymac.local', ip: {192, 168, 15, 157}, port: 5000, txt:
  %{'url' => 'foorl'}}, nil}, []}