Implement the WHIP protocol.

rtpconn/whipclient.go

@@ -0,0 +1,213 @@
+package rtpconn
+
+import (
+	"context"
+	"errors"
+	"sync"
+
+	"github.com/jech/galene/conn"
+	"github.com/jech/galene/group"
+	"github.com/pion/webrtc/v3"
+)
+
+type WhipClient struct {
+	group    *group.Group
+	id       string
+	token    string
+	username string
+
+	mu          sync.Mutex
+	permissions []string
+	connection  *rtpUpConnection
+}
+
+func NewWhipClient(g *group.Group, id string, token string) *WhipClient {
+	return &WhipClient{group: g, id: id, token: token}
+}
+
+func (c *WhipClient) Group() *group.Group {
+	return c.group
+}
+
+func (c *WhipClient) Id() string {
+	return c.id
+}
+
+func (c *WhipClient) Token() string {
+	return c.token
+}
+
+func (c *WhipClient) Username() string {
+	return c.username
+}
+
+func (c *WhipClient) SetUsername(username string) {
+	c.username = username
+}
+
+func (c *WhipClient) Permissions() []string {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return c.permissions
+}
+
+func (c *WhipClient) SetPermissions(perms []string) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.permissions = perms
+}
+
+func (c *WhipClient) Data() map[string]interface{} {
+	return nil
+}
+
+func (c *WhipClient) PushConn(g *group.Group, id string, conn conn.Up, tracks []conn.UpTrack, replace string) error {
+	return nil
+}
+
+func (c *WhipClient) RequestConns(target group.Client, g *group.Group, id string) error {
+	if g != c.group {
+		return nil
+	}
+
+	c.mu.Lock()
+	up := c.connection
+	c.mu.Unlock()
+	if up == nil {
+		return nil
+	}
+	tracks := up.getTracks()
+	ts := make([]conn.UpTrack, len(tracks))
+	for i, t := range tracks {
+		ts[i] = t
+	}
+	target.PushConn(g, up.Id(), up, ts, "")
+	return nil
+}
+
+func (c *WhipClient) Joined(group, kind string) error {
+	return nil
+}
+
+func (c *WhipClient) PushClient(group, kind, id, username string, permissions []string, status map[string]interface{}) error {
+	return nil
+}
+
+func (c *WhipClient) Kick(id string, user *string, message string) error {
+	return c.Close()
+}
+
+func (c *WhipClient) Close() error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	g := c.group
+	if g == nil {
+		return nil
+	}
+	if c.connection != nil {
+		id := c.connection.Id()
+		c.connection.pc.OnICEConnectionStateChange(nil)
+		c.connection.pc.Close()
+		c.connection = nil
+		for _, c := range g.GetClients(c) {
+			c.PushConn(g, id, nil, nil, "")
+		}
+		c.connection = nil
+	}
+	group.DelClient(c)
+	c.group = nil
+	return nil
+}
+
+func (c *WhipClient) NewConnection(ctx context.Context, offer []byte) ([]byte, error) {
+	conn, err := newUpConn(c, c.id, "", string(offer))
+	if err != nil {
+		return nil, err
+	}
+
+	conn.pc.OnICEConnectionStateChange(
+		func(state webrtc.ICEConnectionState) {
+			switch state {
+			case webrtc.ICEConnectionStateFailed,
+				webrtc.ICEConnectionStateClosed:
+				c.Close()
+			}
+		})
+
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if c.connection != nil {
+		conn.pc.OnICEConnectionStateChange(nil)
+		conn.pc.Close()
+		return nil, errors.New("duplicate connection")
+	}
+	c.connection = conn
+
+	answer, err := c.gotOffer(ctx, offer)
+	if err != nil {
+		conn.pc.OnICEConnectionStateChange(nil)
+		conn.pc.Close()
+		return nil, err
+	}
+
+	return answer, nil
+}
+
+func (c *WhipClient) GotOffer(ctx context.Context, offer []byte) ([]byte, error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return c.gotOffer(ctx, offer)
+}
+
+// called locked
+func (c *WhipClient) gotOffer(ctx context.Context, offer []byte) ([]byte, error) {
+	conn := c.connection
+	err := conn.pc.SetRemoteDescription(webrtc.SessionDescription{
+		Type: webrtc.SDPTypeOffer,
+		SDP:  string(offer),
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	answer, err := conn.pc.CreateAnswer(nil)
+	if err != nil {
+		return nil, err
+	}
+
+	gatherComplete := webrtc.GatheringCompletePromise(conn.pc)
+
+	err = conn.pc.SetLocalDescription(answer)
+	if err != nil {
+		return nil, err
+	}
+
+	conn.flushICECandidates()
+
+	select {
+	case <-ctx.Done():
+		return nil, ctx.Err()
+	case <-gatherComplete:
+	}
+
+	return []byte(conn.pc.CurrentLocalDescription().SDP), nil
+}
+
+func (c *WhipClient) GotICECandidate(candidate, ufrag []byte) error {
+	zero := uint16(0)
+	init := webrtc.ICECandidateInit{
+		Candidate:     string(candidate),
+		SDPMLineIndex: &zero,
+	}
+	if ufrag != nil {
+		u := string(ufrag)
+		init.UsernameFragment = &u
+	}
+
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if c.connection == nil {
+		return nil
+	}
+	return c.connection.addICECandidate(&init)
+}