move redirect support into Describe()

connclient.go

@@ -292,6 +292,37 @@ func (c *ConnClient) Describe(u *base.URL) (Tracks, *base.Response, error) {
 	}
 
 	if res.StatusCode != base.StatusOK {
+		// redirect
+		if !c.d.RedirectDisable &&
+			res.StatusCode >= base.StatusMovedPermanently &&
+			res.StatusCode <= base.StatusUseProxy &&
+			len(res.Header["Location"]) == 1 {
+
+			c.Close()
+
+			u, err := base.ParseURL(res.Header["Location"][0])
+			if err != nil {
+				return nil, nil, err
+			}
+
+			nc, err := c.d.Dial(u.Host)
+			if err != nil {
+				return nil, nil, err
+			}
+			*c = *nc
+
+			res, err := c.Options(u)
+			if err != nil {
+				// since this method is not implemented by every RTSP server,
+				// return only if status code is not 404
+				if res == nil || res.StatusCode != base.StatusNotFound {
+					return nil, nil, err
+				}
+			}
+
+			return c.Describe(u)
+		}
+
 		return nil, res, fmt.Errorf("bad status code: %d (%s)", res.StatusCode, res.StatusMessage)
 	}
 
@@ -309,55 +340,18 @@ func (c *ConnClient) Describe(u *base.URL) (Tracks, *base.Response, error) {
 		return nil, nil, err
 	}
 
+	for _, t := range tracks {
+		t.BaseUrl = u
+	}
+
 	return tracks, res, nil
 }
 
-// build an URL by merging baseUrl with the control attribute from track.Media.
-func (c *ConnClient) urlForTrack(baseUrl *base.URL, mode headers.TransportMode, track *Track) *base.URL {
-	control := func() string {
-		// if we're publishing, get control from track ID
-		if mode == headers.TransportModeRecord {
-			return "trackID=" + strconv.FormatInt(int64(track.Id), 10)
-		}
-
-		// otherwise, get from media attributes
-		for _, attr := range track.Media.Attributes {
-			if attr.Key == "control" {
-				return attr.Value
-			}
-		}
-		return ""
-	}()
-
-	// no control attribute, use base URL
-	if control == "" {
-		return baseUrl
-	}
-
-	// control attribute contains an absolute path
-	if strings.HasPrefix(control, "rtsp://") {
-		newUrl, err := base.ParseURL(control)
-		if err != nil {
-			return baseUrl
-		}
-
-		// copy host and credentials
-		newUrl.Host = baseUrl.Host
-		newUrl.User = baseUrl.User
-		return newUrl
-	}
-
-	// control attribute contains a relative control attribute
-	newUrl := baseUrl.Clone()
-	newUrl.AddControlAttribute(control)
-	return newUrl
-}
-
 // Setup writes a SETUP request and reads a Response.
 // rtpPort and rtcpPort are used only if protocol is UDP.
 // if rtpPort and rtcpPort are zero, they are chosen automatically.
-func (c *ConnClient) Setup(u *base.URL, mode headers.TransportMode,
-	track *Track, rtpPort int, rtcpPort int) (*base.Response, error) {
+func (c *ConnClient) Setup(mode headers.TransportMode, track *Track,
+	rtpPort int, rtcpPort int) (*base.Response, error) {
 	err := c.checkState(map[connClientState]struct{}{
 		connClientStateInitial:   {},
 		connClientStatePrePlay:   {},
@@ -376,8 +370,8 @@ func (c *ConnClient) Setup(u *base.URL, mode headers.TransportMode,
 		return nil, fmt.Errorf("cannot read and publish at the same time")
 	}
 
-	if c.streamUrl != nil && *u != *c.streamUrl {
-		return nil, fmt.Errorf("setup has already begun with another url")
+	if c.streamUrl != nil && *track.BaseUrl != *c.streamUrl {
+		return nil, fmt.Errorf("cannot setup tracks with different base urls")
 	}
 
 	var rtpListener *connClientUDPListener
@@ -465,9 +459,18 @@ func (c *ConnClient) Setup(u *base.URL, mode headers.TransportMode,
 		transport.InterleavedIds = &[2]int{(track.Id * 2), (track.Id * 2) + 1}
 	}
 
+	trackUrl, err := track.Url(mode)
+	if err != nil {
+		if proto == StreamProtocolUDP {
+			rtpListener.close()
+			rtcpListener.close()
+		}
+		return nil, err
+	}
+
 	res, err := c.Do(&base.Request{
 		Method: base.SETUP,
-		URL:    c.urlForTrack(u, mode, track),
+		URL:    trackUrl,
 		Header: base.Header{
 			"Transport": transport.Write(),
 		},
@@ -494,7 +497,7 @@ func (c *ConnClient) Setup(u *base.URL, mode headers.TransportMode,
 			v := StreamProtocolTCP
 			c.streamProtocol = &v
 
-			return c.Setup(u, headers.TransportModePlay, track, 0, 0)
+			return c.Setup(headers.TransportModePlay, track, 0, 0)
 		}
 
 		return res, fmt.Errorf("bad status code: %d (%s)", res.StatusCode, res.StatusMessage)
@@ -545,7 +548,7 @@ func (c *ConnClient) Setup(u *base.URL, mode headers.TransportMode,
 		c.rtcpSenders[track.Id] = rtcpsender.New(clockRate)
 	}
 
-	c.streamUrl = u
+	c.streamUrl = track.BaseUrl
 	c.streamProtocol = &proto
 	c.tracks = append(c.tracks, track)
 

connclientpublish.go

@@ -16,6 +16,12 @@ func (c *ConnClient) Announce(u *base.URL, tracks Tracks) (*base.Response, error
 		return nil, err
 	}
 
+	// fill id and base url
+	for i, t := range tracks {
+		t.Id = i
+		t.BaseUrl = u
+	}
+
 	res, err := c.Do(&base.Request{
 		Method: base.ANNOUNCE,
 		URL:    u,

dialer.go

@@ -33,31 +33,37 @@ func DialPublish(address string, tracks Tracks) (*ConnClient, error) {
 }
 
 // Dialer allows to initialize a ConnClient.
+// All fields are optional.
 type Dialer struct {
-	// (optional) the stream protocol (UDP or TCP).
+	// the stream protocol (UDP or TCP).
 	// If nil, it is chosen automatically (first UDP, then, if it fails, TCP).
+	// It defaults to nil.
 	StreamProtocol *StreamProtocol
 
-	// (optional) timeout of read operations.
-	// It defaults to 10 seconds
+	// timeout of read operations.
+	// It defaults to 10 seconds.
 	ReadTimeout time.Duration
 
-	// (optional) timeout of write operations.
-	// It defaults to 10 seconds
+	// timeout of write operations.
+	// It defaults to 10 seconds.
 	WriteTimeout time.Duration
 
-	// (optional) read buffer count.
+	// disable being redirected to other servers, that can happen during Describe().
+	// It defaults to false.
+	RedirectDisable bool
+
+	// read buffer count.
 	// If greater than 1, allows to pass buffers to routines different than the one
 	// that is reading frames.
-	// It defaults to 1
+	// It defaults to 1.
 	ReadBufferCount int
 
-	// (optional) function used to initialize the TCP client.
-	// It defaults to net.DialTimeout
+	// function used to initialize the TCP client.
+	// It defaults to net.DialTimeout.
 	DialTimeout func(network, address string, timeout time.Duration) (net.Conn, error)
 
-	// (optional) function used to initialize UDP listeners.
-	// It defaults to net.ListenPacket
+	// function used to initialize UDP listeners.
+	// It defaults to net.ListenPacket.
 	ListenPacket func(network, address string) (net.PacketConn, error)
 }
 
@@ -127,20 +133,12 @@ func (d Dialer) DialRead(address string) (*ConnClient, error) {
 
 	tracks, res, err := conn.Describe(u)
 	if err != nil {
-		// redirect
-		if res != nil && res.StatusCode >= base.StatusMovedPermanently &&
-			res.StatusCode <= base.StatusUseProxy &&
-			len(res.Header["Location"]) == 1 {
-			conn.Close()
-			return d.DialRead(res.Header["Location"][0])
-		}
-
 		conn.Close()
 		return nil, err
 	}
 
 	for _, track := range tracks {
-		_, err := conn.Setup(u, headers.TransportModePlay, track, 0, 0)
+		_, err := conn.Setup(headers.TransportModePlay, track, 0, 0)
 		if err != nil {
 			conn.Close()
 			return nil, err
@@ -185,7 +183,7 @@ func (d Dialer) DialPublish(address string, tracks Tracks) (*ConnClient, error)
 	}
 
 	for _, track := range tracks {
-		_, err := conn.Setup(u, headers.TransportModeRecord, track, 0, 0)
+		_, err := conn.Setup(headers.TransportModeRecord, track, 0, 0)
 		if err != nil {
 			conn.Close()
 			return nil, err

dialer_test.go

@@ -301,7 +301,7 @@ func TestDialPublishSerial(t *testing.T) {
 			sps, pps, err := decoder.ReadSPSPPS()
 			require.NoError(t, err)
 
-			track, err := NewTrackH264(0, sps, pps)
+			track, err := NewTrackH264(96, sps, pps)
 			require.NoError(t, err)
 
 			dialer := Dialer{
@@ -381,7 +381,7 @@ func TestDialPublishParallel(t *testing.T) {
 			sps, pps, err := decoder.ReadSPSPPS()
 			require.NoError(t, err)
 
-			track, err := NewTrackH264(0, sps, pps)
+			track, err := NewTrackH264(96, sps, pps)
 			require.NoError(t, err)
 
 			writerDone := make(chan struct{})
@@ -475,7 +475,7 @@ func TestDialPublishPauseSerial(t *testing.T) {
 			sps, pps, err := decoder.ReadSPSPPS()
 			require.NoError(t, err)
 
-			track, err := NewTrackH264(0, sps, pps)
+			track, err := NewTrackH264(96, sps, pps)
 			require.NoError(t, err)
 
 			dialer := Dialer{
@@ -547,7 +547,7 @@ func TestDialPublishPauseParallel(t *testing.T) {
 			sps, pps, err := decoder.ReadSPSPPS()
 			require.NoError(t, err)
 
-			track, err := NewTrackH264(0, sps, pps)
+			track, err := NewTrackH264(96, sps, pps)
 			require.NoError(t, err)
 
 			dialer := Dialer{

examples/client-publish-options.go

@@ -38,7 +38,7 @@ func main() {
 	fmt.Println("stream connected")
 
 	// create a H264 track
-	track, err := gortsplib.NewTrackH264(0, sps, pps)
+	track, err := gortsplib.NewTrackH264(96, sps, pps)
 	if err != nil {
 		panic(err)
 	}

examples/client-publish-pause.go

@@ -39,7 +39,7 @@ func main() {
 	fmt.Println("stream connected")
 
 	// create a H264 track
-	track, err := gortsplib.NewTrackH264(0, sps, pps)
+	track, err := gortsplib.NewTrackH264(96, sps, pps)
 	if err != nil {
 		panic(err)
 	}

examples/client-publish.go

@@ -36,7 +36,7 @@ func main() {
 	fmt.Println("stream connected")
 
 	// create a H264 track
-	track, err := gortsplib.NewTrackH264(0, sps, pps)
+	track, err := gortsplib.NewTrackH264(96, sps, pps)
 	if err != nil {
 		panic(err)
 	}

track.go

@@ -10,28 +10,32 @@ import (
 	"github.com/notedit/rtmp/codec/aac"
 	psdp "github.com/pion/sdp/v3"
 
+	"github.com/aler9/gortsplib/pkg/base"
+	"github.com/aler9/gortsplib/pkg/headers"
 	"github.com/aler9/gortsplib/pkg/sdp"
 )
 
 // Track is a track available in a certain URL.
 type Track struct {
-	// track id
+	// base url
+	BaseUrl *base.URL
+
+	// id
 	Id int
 
-	// track codec and info in SDP format
+	// codec and info in SDP format
 	Media *psdp.MediaDescription
 }
 
 // NewTrackH264 initializes an H264 track.
-func NewTrackH264(id int, sps []byte, pps []byte) (*Track, error) {
+func NewTrackH264(payloadType uint8, sps []byte, pps []byte) (*Track, error) {
 	spropParameterSets := base64.StdEncoding.EncodeToString(sps) +
 		"," + base64.StdEncoding.EncodeToString(pps)
 	profileLevelId := strings.ToUpper(hex.EncodeToString(sps[1:4]))
 
-	typ := strconv.FormatInt(int64(96+id), 10)
+	typ := strconv.FormatInt(int64(payloadType), 10)
 
 	return &Track{
-		Id: id,
 		Media: &psdp.MediaDescription{
 			MediaName: psdp.MediaName{
 				Media:   "video",
@@ -55,7 +59,7 @@ func NewTrackH264(id int, sps []byte, pps []byte) (*Track, error) {
 }
 
 // NewTrackAAC initializes an AAC track.
-func NewTrackAAC(id int, config []byte) (*Track, error) {
+func NewTrackAAC(payloadType uint8, config []byte) (*Track, error) {
 	codec, err := aac.FromMPEG4AudioConfigBytes(config)
 	if err != nil {
 		return nil, err
@@ -77,10 +81,9 @@ func NewTrackAAC(id int, config []byte) (*Track, error) {
 		return nil, err
 	}
 
-	typ := strconv.FormatInt(int64(96+id), 10)
+	typ := strconv.FormatInt(int64(payloadType), 10)
 
 	return &Track{
-		Id: id,
 		Media: &psdp.MediaDescription{
 			MediaName: psdp.MediaName{
 				Media:   "audio",
@@ -159,6 +162,51 @@ func (t *Track) ClockRate() (int, error) {
 	return 0, fmt.Errorf("attribute 'rtpmap' not found")
 }
 
+// Url returns the track url.
+func (t *Track) Url(mode headers.TransportMode) (*base.URL, error) {
+	if t.BaseUrl == nil {
+		return nil, fmt.Errorf("empty base url")
+	}
+
+	control := func() string {
+		// if we're publishing, get control from track ID
+		if mode == headers.TransportModeRecord {
+			return "trackID=" + strconv.FormatInt(int64(t.Id), 10)
+		}
+
+		// otherwise, get from media attributes
+		for _, attr := range t.Media.Attributes {
+			if attr.Key == "control" {
+				return attr.Value
+			}
+		}
+		return ""
+	}()
+
+	// no control attribute, use base URL
+	if control == "" {
+		return t.BaseUrl, nil
+	}
+
+	// control attribute contains an absolute path
+	if strings.HasPrefix(control, "rtsp://") {
+		ur, err := base.ParseURL(control)
+		if err != nil {
+			return nil, err
+		}
+
+		// copy host and credentials
+		ur.Host = t.BaseUrl.Host
+		ur.User = t.BaseUrl.User
+		return ur, nil
+	}
+
+	// control attribute contains a relative control attribute
+	ur := t.BaseUrl.Clone()
+	ur.AddControlAttribute(control)
+	return ur, nil
+}
+
 // Tracks is a list of tracks.
 type Tracks []*Track