Add proxy example (#141) (#175)

* cleanup

* add proxy example

README.md

@@ -93,6 +93,7 @@ Features:
 * [server](examples/server/main.go)
 * [server-tls](examples/server-tls/main.go)
 * [server-h264-save-to-disk](examples/server-h264-save-to-disk/main.go)
+* [proxy](examples/proxy/main.go)
 
 ## API Documentation
 

client_format.go

@@ -32,27 +32,27 @@ func newClientFormat(cm *clientMedia, forma format.Format) *clientFormat {
 	}
 }
 
-func (ct *clientFormat) start(cm *clientMedia) {
-	if cm.c.state == clientStatePlay {
-		if cm.udpRTPListener != nil {
+func (ct *clientFormat) start() {
+	if ct.cm.c.state == clientStatePlay {
+		if ct.cm.udpRTPListener != nil {
 			ct.udpReorderer = rtpreorderer.New()
 			ct.udpRTCPReceiver = rtcpreceiver.New(
-				cm.c.udpReceiverReportPeriod,
+				ct.cm.c.udpReceiverReportPeriod,
 				nil,
 				ct.format.ClockRate(), func(pkt rtcp.Packet) {
-					cm.writePacketRTCP(pkt)
+					ct.cm.writePacketRTCP(pkt)
 				})
 		}
 	} else {
 		ct.rtcpSender = rtcpsender.New(
 			ct.format.ClockRate(),
 			func(pkt rtcp.Packet) {
-				cm.writePacketRTCP(pkt)
+				ct.cm.writePacketRTCP(pkt)
 			})
 	}
 }
 
-// start RTCP senders after write() has been allocated in order to avoid a crash
+// start writing after write*() has been allocated in order to avoid a crash
 func (ct *clientFormat) startWriting() {
 	if ct.c.state != clientStatePlay && !ct.c.DisableRTCPSenderReports {
 		ct.rtcpSender.Start(ct.c.senderReportPeriod)

client_media.go

@@ -121,7 +121,7 @@ func (cm *clientMedia) start() {
 	}
 
 	for _, ct := range cm.formats {
-		ct.start(cm)
+		ct.start()
 	}
 
 	if cm.udpRTPListener != nil {

examples/client-read/main.go

@@ -11,8 +11,9 @@ import (
 	"github.com/pion/rtp"
 )
 
-// This example shows how to connect to a RTSP server
-// and read all medias on a path.
+// This example shows how to
+// 1. connect to a RTSP server
+// 2. read all media streams on a path.
 
 func main() {
 	c := gortsplib.Client{}

examples/proxy/client.go

@@ -0,0 +1,109 @@
+package main
+
+import (
+	"log"
+	"sync"
+	"time"
+
+	"github.com/aler9/gortsplib/v2"
+	"github.com/aler9/gortsplib/v2/pkg/format"
+	"github.com/aler9/gortsplib/v2/pkg/media"
+	"github.com/aler9/gortsplib/v2/pkg/url"
+	"github.com/pion/rtp"
+)
+
+const (
+	existingStream = "rtsp://x.x.x.x:8554/mystream"
+	reconnectPause = 2 * time.Second
+)
+
+type client struct {
+	mutex  sync.RWMutex
+	stream *gortsplib.ServerStream
+}
+
+func newClient() *client {
+	c := &client{}
+
+	// start a separated routine
+	go c.run()
+
+	return c
+}
+
+func (c *client) run() {
+	for {
+		err := c.read()
+		log.Printf("ERR: %s\n", err)
+
+		time.Sleep(reconnectPause)
+	}
+}
+
+func (c *client) getStream() *gortsplib.ServerStream {
+	c.mutex.RLock()
+	defer c.mutex.RUnlock()
+	return c.stream
+}
+
+func (c *client) read() error {
+	rc := gortsplib.Client{}
+
+	// parse URL
+	u, err := url.Parse(existingStream)
+	if err != nil {
+		return err
+	}
+
+	// connect to the server
+	err = rc.Start(u.Scheme, u.Host)
+	if err != nil {
+		return err
+	}
+	defer rc.Close()
+
+	// find published medias
+	medias, baseURL, _, err := rc.Describe(u)
+	if err != nil {
+		return err
+	}
+
+	// setup all medias
+	err = rc.SetupAll(medias, baseURL)
+	if err != nil {
+		return err
+	}
+
+	// create a server stream
+	stream := gortsplib.NewServerStream(medias)
+	defer stream.Close()
+
+	log.Printf("stream is ready and can be read from the server at rtsp://localhost:8554/stream\n")
+
+	// make stream available by using getStream()
+	c.mutex.Lock()
+	c.stream = stream
+	c.mutex.Unlock()
+
+	defer func() {
+		// remove stream from getStream()
+		c.mutex.Lock()
+		c.stream = nil
+		c.mutex.Unlock()
+	}()
+
+	// called when a RTP packet arrives
+	rc.OnPacketRTPAny(func(medi *media.Media, forma format.Format, pkt *rtp.Packet) {
+		// route incoming packets to the server stream
+		stream.WritePacketRTP(medi, pkt)
+	})
+
+	// start playing
+	_, err = rc.Play(nil)
+	if err != nil {
+		return err
+	}
+
+	// wait until a fatal error
+	return rc.Wait()
+}

examples/proxy/main.go

@@ -0,0 +1,14 @@
+package main
+
+// This example shows how to
+// 1. read an existing stream from an external server or camera, with a client
+// 2. create a server that allow to proxy that stream
+
+func main() {
+	// allocate the client
+	c := newClient()
+
+	// allocate the server.
+	// give server access to the method client.getStream().
+	newServer(c.getStream)
+}

examples/proxy/server.go

@@ -0,0 +1,100 @@
+package main
+
+import (
+	"log"
+
+	"github.com/aler9/gortsplib/v2"
+	"github.com/aler9/gortsplib/v2/pkg/base"
+)
+
+type server struct {
+	getStream func() *gortsplib.ServerStream
+}
+
+func newServer(
+	getStream func() *gortsplib.ServerStream,
+) *server {
+	s := &server{
+		getStream: getStream,
+	}
+
+	// configure the server
+	rs := &gortsplib.Server{
+		Handler:           s,
+		RTSPAddress:       ":8554",
+		UDPRTPAddress:     ":8000",
+		UDPRTCPAddress:    ":8001",
+		MulticastIPRange:  "224.1.0.0/16",
+		MulticastRTPPort:  8002,
+		MulticastRTCPPort: 8003,
+	}
+
+	// start server and wait until a fatal error
+	log.Printf("server is ready")
+	panic(rs.StartAndWait())
+}
+
+// called when a connection is opened.
+func (s *server) OnConnOpen(ctx *gortsplib.ServerHandlerOnConnOpenCtx) {
+	log.Printf("conn opened")
+}
+
+// called when a connection is closed.
+func (s *server) OnConnClose(ctx *gortsplib.ServerHandlerOnConnCloseCtx) {
+	log.Printf("conn closed (%v)", ctx.Error)
+}
+
+// called when a session is opened.
+func (s *server) OnSessionOpen(ctx *gortsplib.ServerHandlerOnSessionOpenCtx) {
+	log.Printf("session opened")
+}
+
+// called when a session is closed.
+func (s *server) OnSessionClose(ctx *gortsplib.ServerHandlerOnSessionCloseCtx) {
+	log.Printf("session closed")
+}
+
+// called when receiving a DESCRIBE request.
+func (s *server) OnDescribe(ctx *gortsplib.ServerHandlerOnDescribeCtx) (*base.Response, *gortsplib.ServerStream, error) {
+	log.Printf("describe request")
+
+	stream := s.getStream()
+
+	// stream is not available yet
+	if stream == nil {
+		return &base.Response{
+			StatusCode: base.StatusNotFound,
+		}, nil, nil
+	}
+
+	return &base.Response{
+		StatusCode: base.StatusOK,
+	}, stream, nil
+}
+
+// called when receiving a SETUP request.
+func (s *server) OnSetup(ctx *gortsplib.ServerHandlerOnSetupCtx) (*base.Response, *gortsplib.ServerStream, error) {
+	log.Printf("setup request")
+
+	stream := s.getStream()
+
+	// stream is not available yet
+	if stream == nil {
+		return &base.Response{
+			StatusCode: base.StatusNotFound,
+		}, nil, nil
+	}
+
+	return &base.Response{
+		StatusCode: base.StatusOK,
+	}, stream, nil
+}
+
+// called when receiving a PLAY request.
+func (s *server) OnPlay(ctx *gortsplib.ServerHandlerOnPlayCtx) (*base.Response, error) {
+	log.Printf("play request")
+
+	return &base.Response{
+		StatusCode: base.StatusOK,
+	}, nil
+}

examples/server-h264-save-to-disk/main.go

@@ -127,7 +127,7 @@ func (sh *serverHandler) OnRecord(ctx *gortsplib.ServerHandlerOnRecordCtx) (*bas
 }
 
 func main() {
-	// configure server
+	// configure the server
 	s := &gortsplib.Server{
 		Handler:           &serverHandler{},
 		RTSPAddress:       ":8554",

examples/server-tls/main.go

@@ -145,7 +145,7 @@ func main() {
 		panic(err)
 	}
 
-	// configure server
+	// configure the server
 	s := &gortsplib.Server{
 		Handler:     &serverHandler{},
 		TLSConfig:   &tls.Config{Certificates: []tls.Certificate{cert}},

examples/server/main.go

@@ -136,7 +136,7 @@ func (sh *serverHandler) OnRecord(ctx *gortsplib.ServerHandlerOnRecordCtx) (*bas
 }
 
 func main() {
-	// configure server
+	// configure the server
 	s := &gortsplib.Server{
 		Handler:           &serverHandler{},
 		RTSPAddress:       ":8554",

server_multicast_writer.go

@@ -12,7 +12,7 @@ type typeAndPayload struct {
 	payload []byte
 }
 
-type serverMulticastHandler struct {
+type serverMulticastWriter struct {
 	rtpl        *serverUDPListener
 	rtcpl       *serverUDPListener
 	writeBuffer *ringbuffer.RingBuffer
@@ -20,7 +20,7 @@ type serverMulticastHandler struct {
 	writerDone chan struct{}
 }
 
-func newServerMulticastHandler(s *Server) (*serverMulticastHandler, error) {
+func newServerMulticastWriter(s *Server) (*serverMulticastWriter, error) {
 	res := make(chan net.IP)
 	select {
 	case s.streamMulticastIP <- streamMulticastIPReq{res: res}:
@@ -42,7 +42,7 @@ func newServerMulticastHandler(s *Server) (*serverMulticastHandler, error) {
 
 	wb, _ := ringbuffer.New(uint64(s.WriteBufferCount))
 
-	h := &serverMulticastHandler{
+	h := &serverMulticastWriter{
 		rtpl:        rtpl,
 		rtcpl:       rtcpl,
 		writeBuffer: wb,
@@ -54,18 +54,18 @@ func newServerMulticastHandler(s *Server) (*serverMulticastHandler, error) {
 	return h, nil
 }
 
-func (h *serverMulticastHandler) close() {
+func (h *serverMulticastWriter) close() {
 	h.rtpl.close()
 	h.rtcpl.close()
 	h.writeBuffer.Close()
 	<-h.writerDone
 }
 
-func (h *serverMulticastHandler) ip() net.IP {
+func (h *serverMulticastWriter) ip() net.IP {
 	return h.rtpl.ip()
 }
 
-func (h *serverMulticastHandler) runWriter() {
+func (h *serverMulticastWriter) runWriter() {
 	defer close(h.writerDone)
 
 	rtpAddr := &net.UDPAddr{
@@ -93,14 +93,14 @@ func (h *serverMulticastHandler) runWriter() {
 	}
 }
 
-func (h *serverMulticastHandler) writePacketRTP(payload []byte) {
+func (h *serverMulticastWriter) writePacketRTP(payload []byte) {
 	h.writeBuffer.Push(typeAndPayload{
 		isRTP:   true,
 		payload: payload,
 	})
 }
 
-func (h *serverMulticastHandler) writePacketRTCP(payload []byte) {
+func (h *serverMulticastWriter) writePacketRTCP(payload []byte) {
 	h.writeBuffer.Push(typeAndPayload{
 		isRTP:   false,
 		payload: payload,

server_session.go

@@ -755,13 +755,6 @@ func (ss *ServerSession) handleRequest(sc *ServerConn, req *base.Request) (*base
 
 		sm := newServerSessionMedia(ss, medi)
 
-		if ss.state == ServerSessionStatePreRecord {
-			sm.formats = make(map[uint8]*serverSessionFormat)
-			for _, forma := range sm.media.Formats {
-				sm.formats[forma.PayloadType()] = newServerSessionFormat(sm, forma)
-			}
-		}
-
 		switch transport {
 		case TransportUDP:
 			sm.udpRTPReadPort = inTH.ClientPorts[0]
@@ -791,7 +784,7 @@ func (ss *ServerSession) handleRequest(sc *ServerConn, req *base.Request) (*base
 			th.Delivery = &de
 			v := uint(127)
 			th.TTL = &v
-			d := stream.streamMedias[medi].multicastHandler.ip()
+			d := stream.streamMedias[medi].multicastWriter.ip()
 			th.Destination = &d
 			th.Ports = &[2]int{ss.s.MulticastRTPPort, ss.s.MulticastRTCPPort}
 

server_session_format.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"time"
 
+	"github.com/pion/rtcp"
 	"github.com/pion/rtp"
 
 	"github.com/aler9/gortsplib/v2/pkg/format"
@@ -27,19 +28,40 @@ func newServerSessionFormat(sm *serverSessionMedia, forma format.Format) *server
 	}
 }
 
-func (st *serverSessionFormat) readRTPUDP(pkt *rtp.Packet, now time.Time) {
-	packets, missing := st.udpReorderer.Process(pkt)
+func (sf *serverSessionFormat) start() {
+	if (*sf.sm.ss.setuppedTransport == TransportUDP || *sf.sm.ss.setuppedTransport == TransportUDPMulticast) &&
+		sf.sm.ss.state != ServerSessionStatePlay {
+		sf.udpReorderer = rtpreorderer.New()
+		sf.udpRTCPReceiver = rtcpreceiver.New(
+			sf.sm.ss.s.udpReceiverReportPeriod,
+			nil,
+			sf.format.ClockRate(),
+			func(pkt rtcp.Packet) {
+				sf.sm.ss.WritePacketRTCP(sf.sm.media, pkt)
+			})
+	}
+}
+
+func (sf *serverSessionFormat) stop() {
+	if sf.udpRTCPReceiver != nil {
+		sf.udpRTCPReceiver.Close()
+		sf.udpRTCPReceiver = nil
+	}
+}
+
+func (sf *serverSessionFormat) readRTPUDP(pkt *rtp.Packet, now time.Time) {
+	packets, missing := sf.udpReorderer.Process(pkt)
 	if missing != 0 {
-		onDecodeError(st.sm.ss, fmt.Errorf("%d RTP packet(s) lost", missing))
+		onDecodeError(sf.sm.ss, fmt.Errorf("%d RTP packet(s) lost", missing))
 		// do not return
 	}
 
 	for _, pkt := range packets {
-		st.udpRTCPReceiver.ProcessPacket(pkt, now, st.format.PTSEqualsDTS(pkt))
-		st.onPacketRTP(pkt)
+		sf.udpRTCPReceiver.ProcessPacket(pkt, now, sf.format.PTSEqualsDTS(pkt))
+		sf.onPacketRTP(pkt)
 	}
 }
 
-func (st *serverSessionFormat) readRTPTCP(pkt *rtp.Packet) {
-	st.onPacketRTP(pkt)
+func (sf *serverSessionFormat) readRTPTCP(pkt *rtp.Packet) {
+	sf.onPacketRTP(pkt)
 }

server_session_media.go

@@ -11,8 +11,6 @@ import (
 
 	"github.com/aler9/gortsplib/v2/pkg/base"
 	"github.com/aler9/gortsplib/v2/pkg/media"
-	"github.com/aler9/gortsplib/v2/pkg/rtcpreceiver"
-	"github.com/aler9/gortsplib/v2/pkg/rtpreorderer"
 )
 
 type serverSessionMedia struct {
@@ -26,7 +24,7 @@ type serverSessionMedia struct {
 	tcpRTPFrame            *base.InterleavedFrame
 	tcpRTCPFrame           *base.InterleavedFrame
 	tcpBuffer              []byte
-	formats                map[uint8]*serverSessionFormat // record
+	formats                map[uint8]*serverSessionFormat // record only
 	writePacketRTPInQueue  func([]byte)
 	writePacketRTCPInQueue func([]byte)
 	readRTP                func([]byte) error
@@ -35,11 +33,20 @@ type serverSessionMedia struct {
 }
 
 func newServerSessionMedia(ss *ServerSession, medi *media.Media) *serverSessionMedia {
-	return &serverSessionMedia{
+	sm := &serverSessionMedia{
 		ss:           ss,
 		media:        medi,
 		onPacketRTCP: func(rtcp.Packet) {},
 	}
+
+	if ss.state == ServerSessionStatePreRecord {
+		sm.formats = make(map[uint8]*serverSessionFormat)
+		for _, forma := range medi.Formats {
+			sm.formats[forma.PayloadType()] = newServerSessionFormat(sm, forma)
+		}
+	}
+
+	return sm
 }
 
 func (sm *serverSessionMedia) start() {
@@ -53,19 +60,6 @@ func (sm *serverSessionMedia) start() {
 		} else {
 			sm.readRTP = sm.readRTPUDPRecord
 			sm.readRTCP = sm.readRTCPUDPRecord
-
-			for _, tr := range sm.formats {
-				tr.udpReorderer = rtpreorderer.New()
-
-				cmedia := sm.media
-				tr.udpRTCPReceiver = rtcpreceiver.New(
-					sm.ss.s.udpReceiverReportPeriod,
-					nil,
-					tr.format.ClockRate(),
-					func(pkt rtcp.Packet) {
-						sm.ss.WritePacketRTCP(cmedia, pkt)
-					})
-			}
 		}
 
 	case TransportTCP:
@@ -87,7 +81,7 @@ func (sm *serverSessionMedia) start() {
 
 	if *sm.ss.setuppedTransport == TransportUDP {
 		if sm.ss.state == ServerSessionStatePlay {
-			// firewall opening is performed by RTCP sender reports generated by ServerStream
+			// firewall opening is performed with RTCP sender reports generated by ServerStream
 
 			// readers can send RTCP packets only
 			sm.ss.s.udpRTCPListener.addClient(sm.ss.author.ip(), sm.udpRTCPReadPort, sm)
@@ -100,6 +94,10 @@ func (sm *serverSessionMedia) start() {
 			sm.ss.s.udpRTCPListener.addClient(sm.ss.author.ip(), sm.udpRTCPReadPort, sm)
 		}
 	}
+
+	for _, sf := range sm.formats {
+		sf.start()
+	}
 }
 
 func (sm *serverSessionMedia) stop() {
@@ -108,11 +106,8 @@ func (sm *serverSessionMedia) stop() {
 		sm.ss.s.udpRTCPListener.removeClient(sm)
 	}
 
-	for _, tr := range sm.formats {
-		if tr.udpRTCPReceiver != nil {
-			tr.udpRTCPReceiver.Close()
-			tr.udpRTCPReceiver = nil
-		}
+	for _, sf := range sm.formats {
+		sf.stop()
 	}
 }
 

server_stream.go

@@ -205,9 +205,9 @@ func (st *ServerStream) readerRemove(ss *ServerSession) {
 
 	if len(st.readers) == 0 {
 		for _, media := range st.streamMedias {
-			if media.multicastHandler != nil {
-				media.multicastHandler.close()
-				media.multicastHandler = nil
+			if media.multicastWriter != nil {
+				media.multicastWriter.close()
+				media.multicastWriter = nil
 			}
 		}
 	}
@@ -224,8 +224,8 @@ func (st *ServerStream) readerSetActive(ss *ServerSession) {
 	if *ss.setuppedTransport == TransportUDPMulticast {
 		for medi, sm := range ss.setuppedMedias {
 			streamMedia := st.streamMedias[medi]
-			streamMedia.multicastHandler.rtcpl.addClient(
-				ss.author.ip(), streamMedia.multicastHandler.rtcpl.port(), sm)
+			streamMedia.multicastWriter.rtcpl.addClient(
+				ss.author.ip(), streamMedia.multicastWriter.rtcpl.port(), sm)
 		}
 	} else {
 		st.activeUnicastReaders[ss] = struct{}{}
@@ -243,7 +243,7 @@ func (st *ServerStream) readerSetInactive(ss *ServerSession) {
 	if *ss.setuppedTransport == TransportUDPMulticast {
 		for medi, sm := range ss.setuppedMedias {
 			streamMedia := st.streamMedias[medi]
-			streamMedia.multicastHandler.rtcpl.removeClient(sm)
+			streamMedia.multicastWriter.rtcpl.removeClient(sm)
 		}
 	} else {
 		delete(st.activeUnicastReaders, ss)

server_stream_media.go

@@ -15,7 +15,7 @@ type serverStreamMedia struct {
 	uuid            uuid.UUID
 	media           *media.Media
 	formats         map[uint8]*serverStreamFormat
-	multicastHandler *serverMulticastHandler
+	multicastWriter *serverMulticastWriter
 }
 
 func newServerStreamMedia(st *ServerStream, medi *media.Media) *serverStreamMedia {
@@ -51,19 +51,19 @@ func (sm *serverStreamMedia) close() {
 		}
 	}
 
-	if sm.multicastHandler != nil {
-		sm.multicastHandler.close()
+	if sm.multicastWriter != nil {
+		sm.multicastWriter.close()
 	}
 }
 
 func (sm *serverStreamMedia) allocateMulticastHandler(s *Server) error {
-	if sm.multicastHandler == nil {
-		mh, err := newServerMulticastHandler(s)
+	if sm.multicastWriter == nil {
+		mh, err := newServerMulticastWriter(s)
 		if err != nil {
 			return err
 		}
 
-		sm.multicastHandler = mh
+		sm.multicastWriter = mh
 	}
 	return nil
 }
@@ -89,8 +89,8 @@ func (sm *serverStreamMedia) WritePacketRTPWithNTP(ss *ServerStream, pkt *rtp.Pa
 	}
 
 	// send multicast
-	if sm.multicastHandler != nil {
-		sm.multicastHandler.writePacketRTP(byts)
+	if sm.multicastWriter != nil {
+		sm.multicastWriter.writePacketRTP(byts)
 	}
 }
 
@@ -109,7 +109,7 @@ func (sm *serverStreamMedia) writePacketRTCP(ss *ServerStream, pkt rtcp.Packet)
 	}
 
 	// send multicast
-	if sm.multicastHandler != nil {
-		sm.multicastHandler.writePacketRTCP(byts)
+	if sm.multicastWriter != nil {
+		sm.multicastWriter.writePacketRTCP(byts)
 	}
 }