func (ds *DiscoveryBrowser) Browse(service *NetworkWebSocket_Service, intervalSeconds, timeoutSeconds int) {
// Don't run two browse processes at the same time
if ds.inprogress {
return
}
ds.inprogress = true
entries := make(chan *mdns.ServiceEntry, 255)
recordsCache := make(map[string]*NetworkWebSocket_DNSRecord)
timeout := time.Duration(timeoutSeconds) * time.Second
interval := time.Duration(intervalSeconds) * time.Second
var targetIPv4 *net.UDPAddr
var targetIPv6 *net.UDPAddr
targetIPv4 = network_ipv4Addr
targetIPv6 = network_ipv6Addr
// Only look for Named Web Socket DNS-SD services
params := &mdns.QueryParam{
Service: "_nws._tcp",
Domain: "local",
Timeout: timeout,
Entries: entries,
IPv4mdns: targetIPv4,
IPv6mdns: targetIPv6,
}
go func() {
complete := false
timeoutFinish := time.After(timeout)
intervalFinish := time.After(interval)
// Wait for responses until timeout
for !complete {
select {
case discoveredService, ok := <-entries:
if !ok {
continue
}
serviceRecord, err := NewNetworkWebSocketRecordFromDNSRecord(discoveredService)
if err != nil {
log.Printf("err: %v", err)
continue
}
// Ignore our own NetworkWebSocket services
if service.isOwnProxyService(serviceRecord) {
continue
}
// Ignore previously discovered NetworkWebSocket proxy services
if service.isActiveProxyService(serviceRecord) {
continue
}
// Resolve discovered service hash provided against available services
var sock *NetworkWebSocket
for _, knownService := range service.Channels {
if bcrypt.Match(knownService.serviceName, serviceRecord.Hash_BCrypt) {
sock = knownService
break
}
}
if sock != nil {
// Create new web socket connection toward discovered proxy
if _, dErr := sock.dialFromDNSRecord(serviceRecord); dErr != nil {
log.Printf("err: %v", dErr)
continue
}
} else {
// Store as an unresolved DNS-SD record
recordsCache[serviceRecord.Hash_Base64] = serviceRecord
continue
}
case <-timeoutFinish:
// Replace unresolved DNS records cache
ds.cachedDNSRecords = recordsCache
ds.inprogress = false
case <-intervalFinish:
complete = true
}
}
}()
// Run the mDNS/DNS-SD query
err := mdns.Query(params)
time.Sleep(interval) // sleep until next loop is scheduled
if err != nil {
log.Printf("Could not perform mDNS/DNS-SD query. %v", err)
return
}
}
func (ds *DiscoveryServer) Browse() {
entries := make(chan *mdns.ServiceEntry, 255)
timeout := 2 * time.Second
params := &mdns.QueryParam{
Service: "_ws._tcp",
Domain: "local",
Timeout: timeout,
Entries: entries,
}
go func() {
complete := false
finish := time.After(timeout)
// Wait for responses until timeout
for !complete {
select {
case e, ok := <-entries:
if !ok {
continue
}
nameComponents := strings.Split(e.Name, ".")
shortName := ""
for i := len(nameComponents) - 1; i >= 0; i-- {
if nameComponents[i] == "_ws" {
shortName = strings.Join(nameComponents[:i], ".")
break
}
}
// DEBUG
//log.Printf("Found proxy web socket [%s] @ [%s:%d] TXT[%s]", shortName, e.Host, e.Port, e.Info)
// Is this a BroadcastWebSocket service?
if isValid := NetworkServiceMatcher.MatchString(shortName); !isValid {
continue
}
// Ignore our own BroadcastWebSocket services
if isOwned := advertisedServiceNames[shortName]; isOwned {
continue
}
// Ignore previously discovered BroadcastWebSocket services
if isRegistered := registeredServiceNames[shortName]; isRegistered {
continue
}
// Build websocket data from returned information
servicePath := "/"
serviceParts := strings.FieldsFunc(e.Info, func(r rune) bool {
return r == '=' || r == ',' || r == ';' || r == ' '
})
if len(serviceParts) > 1 {
for i := 0; i < len(serviceParts); i += 2 {
if strings.ToLower(serviceParts[i]) == "path" {
servicePath = serviceParts[i+1]
break
}
}
}
// Generate unique id for connection
rand.Seed(time.Now().UTC().UnixNano())
newPeerId := rand.Int()
// Build URL
remoteWSUrl := &url.URL{
Scheme: "ws",
Host: fmt.Sprintf("%s:%d", e.Host, e.Port),
Path: fmt.Sprintf("%s/%d", servicePath, newPeerId),
}
serviceName := path.Base(servicePath)
// Resolve websocket connection
sock := namedWebSockets[servicePath]
if sock == nil {
sock = NewNamedWebSocket(serviceName, true, ds.Port)
namedWebSockets[servicePath] = sock
}
log.Printf("Establishing proxy broadcast websocket connection to ws://%s%s", remoteWSUrl.Host, remoteWSUrl.Path)
ws, _, nErr := websocket.DefaultDialer.Dial(remoteWSUrl.String(), map[string][]string{
"Origin": []string{ds.Host},
"X-BroadcastWebSocket-Proxy": []string{"true"},
})
if nErr != nil {
log.Printf("Proxy broadcast websocket connection failed: %s", nErr)
return
}
proxyConn := NewProxyConnection(newPeerId, ws, false)
proxyConn.addConnection(sock)
registeredServiceNames[shortName] = true
case <-finish:
complete = true
}
}
}()
// Run the mDNS query
err := mdns.Query(params)
if err != nil {
log.Fatalf("err: %v", err)
}
}
func (ds *DiscoveryBrowser) Browse(service *Service, timeoutSeconds int) {
entries := make(chan *mdns.ServiceEntry, 255)
recordsCache := make(map[string]*DNSRecord, 255)
timeout := time.Duration(timeoutSeconds) * time.Second
var targetIPv4 *net.UDPAddr
var targetIPv6 *net.UDPAddr
targetIPv4 = network_ipv4Addr
targetIPv6 = network_ipv6Addr
// Only look for Network Web Socket DNS-SD services
params := &mdns.QueryParam{
Service: "_nws._tcp",
Domain: "local",
Timeout: timeout,
Entries: entries,
IPv4mdns: targetIPv4,
IPv6mdns: targetIPv6,
}
go func() {
complete := false
timeoutFinish := time.After(timeout)
// Wait for responses until timeout
for !complete {
select {
case discoveredService, ok := <-entries:
if !ok {
continue
}
serviceRecord, err := NewServiceRecordFromDNSRecord(discoveredService)
if err != nil {
log.Printf("err: %v", err)
continue
}
// Ignore our own Channel services
if service.isOwnProxyService(serviceRecord) {
continue
}
// Ignore previously discovered Channel proxy services
if service.isActiveProxyService(serviceRecord) {
continue
}
// Resolve discovered service hash provided against available services
var channel *Channel
for _, knownService := range service.Channels {
if bcrypt.Match(knownService.serviceName, serviceRecord.Hash_BCrypt) {
channel = knownService
break
}
}
if channel != nil {
// Create new web socket connection toward discovered proxy
if dErr := dialProxyFromDNSRecord(serviceRecord, channel); dErr != nil {
log.Printf("err: %v", dErr)
continue
}
} else {
// Store as an unresolved DNS-SD record
recordsCache[serviceRecord.Hash_Base64] = serviceRecord
continue
}
case <-timeoutFinish:
// Replace unresolved DNS records cache
ds.cachedDNSRecords = recordsCache
complete = true
}
}
}()
// Run the mDNS/DNS-SD query
err := mdns.Query(params)
if err != nil {
log.Printf("Could not perform mDNS/DNS-SD query. %v", err)
return
}
}
