1// Copyright 2018 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5package osp 6 7// TODO(pthatcher): 8// - Make our own abstraction that has 9// .InstanceName, .HostName, .MetadataVersion, .FingerPrint 10// rather than using mdns.ServiceEntry 11// - Advertise TXT (text below) with "fp" and "mv" 12 13import ( 14 "context" 15 16 mdns "github.com/grandcat/zeroconf" 17) 18 19const ( 20 MdnsServiceType = "_openscreen._udp" 21 MdnsDomain = "local" 22) 23 24// Returns a channel of mDNS entries 25// The critical parts are entry.Target (name) entry.HostName (address) 26func BrowseMdns(ctx context.Context) (<-chan *mdns.ServiceEntry, error) { 27 entries := make(chan *mdns.ServiceEntry) 28 29 resolver, err := mdns.NewResolver(nil) 30 if err != nil { 31 return entries, err 32 } 33 34 err = resolver.Browse(ctx, MdnsServiceType, MdnsDomain, entries) 35 return entries, err 36} 37 38func RunMdnsServer(ctx context.Context, instance string, port int) error { 39 var text []string 40 server, err := mdns.Register(instance, MdnsServiceType, MdnsDomain, port, text, nil /* ifaces */) 41 if err != nil { 42 return err 43 } 44 waitUntilDone(ctx) 45 server.Shutdown() 46 return nil 47} 48