69 lines
1.2 KiB
Go
69 lines
1.2 KiB
Go
package discovery
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import (
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"context"
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"net"
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"github.com/grandcat/zeroconf"
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"github.com/pkg/errors"
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)
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// Service is a ReachRS service discovered via MDNS-SD
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type Service struct {
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Name string
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AddrV4 *net.IP
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Port int
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}
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// Discover tries to discover ReachRS services on the local network via mDNS-SD
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func Discover(ctx context.Context) ([]Service, error) {
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services := make([]Service, 0)
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watch, err := Watch(ctx)
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if err != nil {
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return nil, errors.WithStack(err)
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}
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for srv := range watch {
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services = append(services, srv)
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}
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return services, nil
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}
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// Watch watches ReachRS services on the local network via mDNS-SD
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func Watch(ctx context.Context) (chan Service, error) {
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out := make(chan Service, 0)
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resolver, err := zeroconf.NewResolver()
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if err != nil {
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return nil, errors.WithStack(err)
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}
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entries := make(chan *zeroconf.ServiceEntry)
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go func() {
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defer close(out)
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for e := range entries {
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var addr *net.IP
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if len(e.AddrIPv4) > 0 {
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addr = &e.AddrIPv4[0]
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}
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srv := Service{
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Name: e.Instance,
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AddrV4: addr,
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Port: e.Port,
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}
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out <- srv
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}
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}()
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if err = resolver.Browse(ctx, "_reach._tcp", ".local", entries); err != nil {
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return nil, err
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}
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return out, nil
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}
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