Add Nest source for WebRTC cameras

pkg/nest/client.go

@@ -0,0 +1,101 @@
+package nest
+
+import (
+	"errors"
+	"github.com/AlexxIT/go2rtc/pkg/core"
+	"github.com/AlexxIT/go2rtc/pkg/webrtc"
+	pion "github.com/pion/webrtc/v3"
+	"net/url"
+)
+
+type Client struct {
+	conn *webrtc.Conn
+}
+
+func NewClient(rawURL string) (*Client, error) {
+	u, err := url.Parse(rawURL)
+	if err != nil {
+		return nil, err
+	}
+
+	query := u.Query()
+	cliendID := query.Get("client_id")
+	cliendSecret := query.Get("client_secret")
+	refreshToken := query.Get("refresh_token")
+	projectID := query.Get("project_id")
+	deviceID := query.Get("device_id")
+
+	if cliendID == "" || cliendSecret == "" || refreshToken == "" || projectID == "" || deviceID == "" {
+		return nil, errors.New("nest: wrong query")
+	}
+
+	nestAPI, err := NewAPI(cliendID, cliendSecret, refreshToken)
+	if err != nil {
+		return nil, err
+	}
+
+	rtcAPI, err := webrtc.NewAPI("")
+	if err != nil {
+		return nil, err
+	}
+
+	conf := pion.Configuration{}
+	pc, err := rtcAPI.NewPeerConnection(conf)
+	if err != nil {
+		return nil, err
+	}
+
+	conn := webrtc.NewConn(pc)
+	conn.Desc = "Nest"
+	conn.Mode = core.ModeActiveProducer
+
+	// https://developers.google.com/nest/device-access/traits/device/camera-live-stream#generatewebrtcstream-request-fields
+	medias := []*core.Media{
+		{Kind: core.KindAudio, Direction: core.DirectionRecvonly},
+		{Kind: core.KindVideo, Direction: core.DirectionRecvonly},
+		{Kind: "app"}, // important for Nest
+	}
+
+	// 3. Create offer with candidates
+	offer, err := conn.CreateCompleteOffer(medias)
+	if err != nil {
+		return nil, err
+	}
+
+	// 4. Exchange SDP via Hass
+	answer, err := nestAPI.ExchangeSDP(projectID, deviceID, offer)
+	if err != nil {
+		return nil, err
+	}
+
+	// 5. Set answer with remote medias
+	if err = conn.SetAnswer(answer); err != nil {
+		return nil, err
+	}
+
+	return &Client{conn: conn}, nil
+}
+
+func (c *Client) GetMedias() []*core.Media {
+	return c.conn.GetMedias()
+}
+
+func (c *Client) GetTrack(media *core.Media, codec *core.Codec) (*core.Receiver, error) {
+	return c.conn.GetTrack(media, codec)
+}
+
+func (c *Client) AddTrack(media *core.Media, codec *core.Codec, track *core.Receiver) error {
+	return c.conn.AddTrack(media, codec, track)
+}
+
+func (c *Client) Start() error {
+	return c.conn.Start()
+}
+
+func (c *Client) Stop() error {
+	return c.conn.Stop()
+}
+
+func (c *Client) MarshalJSON() ([]byte, error) {
+	return c.conn.MarshalJSON()
+}