main.go

package main

import (
	"flag"
	"fmt"

	"github.com/pion/webrtc/v3"

	gst "github.com/pion/example-webrtc-applications/v3/internal/gstreamer-src"
	"github.com/pion/example-webrtc-applications/v3/internal/signal"
)

func main() {
	audioSrc := flag.String("audio-src", "audiotestsrc", "GStreamer audio src")
	videoSrc := flag.String("video-src", "videotestsrc", "GStreamer video src")
	sdpChan := signal.HTTPSDPServer()

	// Everything below is the pion-WebRTC API! Thanks for using it ❤️.

	// Prepare the configuration
	config := webrtc.Configuration{
		ICEServers: []webrtc.ICEServer{
			{
				URLs: []string{"stun:stun.l.google.com:19302"},
			},
		},
	}

	// Create a new RTCPeerConnection
	peerConnection, err := webrtc.NewPeerConnection(config)
	if err != nil {
		panic(err)
	}

	// Set the handler for ICE connection state
	// This will notify you when the peer has connected/disconnected
	peerConnection.OnICEConnectionStateChange(func(connectionState webrtc.ICEConnectionState) {
		fmt.Printf("Connection State has changed %s \n", connectionState.String())
	})

	// Create a audio track
	opusTrack, err := webrtc.NewTrackLocalStaticSample(webrtc.RTPCodecCapability{MimeType: "audio/opus"}, "audio", "pion1")
	if err != nil {
		panic(err)
	} else if _, err = peerConnection.AddTrack(opusTrack); err != nil {
		panic(err)
	}

	// Create a video track
	vp8Track, err := webrtc.NewTrackLocalStaticSample(webrtc.RTPCodecCapability{MimeType: "video/vp8"}, "video", "pion2")
	if err != nil {
		panic(err)
	} else if _, err = peerConnection.AddTrack(vp8Track); err != nil {
		panic(err)
	}

	// Create an offer to send to the browser
	offer, err := peerConnection.CreateOffer(nil)
	if err != nil {
		panic(err)
	}

	// Create channel that is blocked until ICE Gathering is complete
	gatherComplete := webrtc.GatheringCompletePromise(peerConnection)

	// Sets the LocalDescription, and starts our UDP listeners
	if err = peerConnection.SetLocalDescription(offer); err != nil {
		panic(err)
	}

	// Block until ICE Gathering is complete, disabling trickle ICE
	// we do this because we only can exchange one signaling message
	// in a production application you should exchange ICE Candidates via OnICECandidate
	<-gatherComplete

	// Output the offer in base64 so we can paste it in browser
	fmt.Println(signal.Encode(*peerConnection.LocalDescription()))

	// Wait for the answer to be submitted via HTTP
	answer := webrtc.SessionDescription{}
	signal.Decode(<-sdpChan, &answer)

	// Set the remote SessionDescription
	err = peerConnection.SetRemoteDescription(answer)
	if err != nil {
		panic(err)
	}

	// Start pushing buffers on these tracks
	gst.CreatePipeline("opus", []*webrtc.TrackLocalStaticSample{opusTrack}, *audioSrc).Start()
	gst.CreatePipeline("vp8", []*webrtc.TrackLocalStaticSample{vp8Track}, *videoSrc).Start()

	// Block forever
	select {}
}