1 const body
= document
.createElement('body')
2 const root
= document
.createElement('div')
3 document
.title
= "Strapp.io Client"
4 const conf
= {"iceServers": [{ "urls": "stun:stun.1.google.com:19302" }] }
8 /* TODO: duplicate in both client.js and host.js */
9 function getPublicKey() {
10 return new Promise( (resolve
, reject
) => {
11 /* Check local storage for public key */
12 if (!window
.localStorage
.getItem('public-key')) {
13 /* If doesn't exist, generate public and private key pair, store in
15 crypto
.subtle
.generateKey(
18 publicExponent
: new Uint8Array([0x01, 0x00, 0x01]),
19 hash
: {name
: "SHA-256"}
22 ['encrypt', 'decrypt']
24 /* TODO: Do we need to store the private key as well? */
25 crypto
.subtle
.exportKey('jwk', keyPair
.publicKey
)
26 .then((exportedKey
) => {
27 window
.localStorage
.setItem('publicKey', exportedKey
)
28 console
.log('public key is' + window
.localStorage
.getItem('publicKey'))
35 resolve(window
.localStorage
.getItem('publicKey'))
41 function sendHost(url
, data
) {
42 const request
= new XMLHttpRequest()
43 request
.open('POST', url
, true)
44 request
.setRequestHeader('Content-Type', 'application/json' )
45 request
.setRequestHeader('X-Strapp-Type', 'ice-candidate-submission')
49 /* Poll the server. Send get request, wait for timeout, send another request.
50 Do this until...? Can be used for either reconnecting or waiting for answer*/
51 function requestHostAnswer(url
, data
) {
52 return new Promise((resolve
, reject
) => {
53 const request
= new XMLHttpRequest()
54 request
.open('GET', url
, true)
55 /* But there is no JSON? */
56 request
.setRequestHeader('Content-Type', 'application/json' )
57 request
.setRequestHeader('X-Strapp-Type', 'client-sdp-offer')
58 request
.setRequestHeader('X-Client-Offer', JSON
.stringify(data
))
59 request
.onreadystatechange
= () => {
60 if (request
.status
=== 200) {
61 if(request
.readyState
=== 4) {
62 console
.log('Client: Recieved Answer from Host')
64 resolve(request
.response
)
67 else if (request
.status
=== 504) {
68 console
.log('timed out, resending')
69 resolve(requestHostAnswer(url
, data
))
72 reject('server unhandled response of status ' + request
.status
)
79 /* Poll server for ice candidates until ice is complete */
80 function requestHostICE(cpc
, url
, pubKey
) {
81 let intervalID
= window
.setInterval(() => {
82 if (cpc
.iceConnectionState
.localeCompare('connected') !== 0
83 && cpc
.iceConnectionState
.localeCompare('completed') !== 0) {
84 console
.log('Client: Polling server begin for intervalID = ' + intervalID
)
85 console
.log('Client: Requesting ICE Candidates from server')
86 const request
= new XMLHttpRequest()
87 request
.open('GET', url
, true)
88 request
.setRequestHeader('Content-Type', 'application/json' )
89 request
.setRequestHeader('X-Strapp-Type', 'ice-candidate-request')
90 request
.setRequestHeader('X-client-pubkey', pubKey
)
91 request
.onreadystatechange
= () => {
92 if (request
.status
=== 200) {
93 if(request
.readyState
=== 4) {
94 console
.log('Client: Recieved ICE response from Host')
95 let response
= JSON
.parse(request
.response
)
96 switch(response
['iceState']) {
98 cpc
.addIceCandidate(new RTCIceCandidate(response
.ice
))
100 case "g": /* Gathering so let interval keep polling */
102 case "c": /* host iceState == Complete, stop bugging it */
103 clearInterval(intervalID
)
107 console
.log('Unhandled iceState in requestHostICE()' + response
['iceState'])
113 console
.log('server unhandled response of status ' + request
.status
)
114 clearInterval(intervalID
)
121 clearInterval(intervalID
)
126 /* Create and send offer -> Send ICE Candidates -> Poll for ICE Candidates */
127 getPublicKey().then((cpk
) => {
128 console
.log('Client: Create and send offer')
129 const cpc
= new RTCPeerConnection(conf
)
131 cpc
.oniceconnectionstatechange
= () => {
132 console
.log('iceConnectionState = ' + cpc
.iceConnectionState
)
135 cpc
.onnegotiationneeded
= () => {
136 console
.log('negotiation needed!')
137 cpc
.createOffer().then((offer
) => {
138 return cpc
.setLocalDescription(offer
)
141 console
.log('Client: Sending offer to host')
144 sdp
: cpc
.localDescription
,
147 return requestHostAnswer(window
.location
, offer
)
149 .then((serverResponse
) => {
150 const answer
= JSON
.parse(serverResponse
)
151 console
.log('Client: Polling for ICE candidates')
152 requestHostICE(cpc
, window
.location
, cpk
.n
)
153 cpc
.setRemoteDescription(answer
.sdp
)
154 cpc
.onicecandidate
= (event
) => {
155 if (event
.candidate
) {
156 console
.log('Client: Sending ice candidate to host')
157 sendHost(window
.location
, JSON
.stringify({
159 ice
: event
.candidate
,
164 console
.log('Client: No more Ice Candidates to send')
170 console
.log('error in sdp handshake: ' + err
)
173 /* Start data channel */
174 dataChannel
= cpc
.createDataChannel("sendChannel");
175 cpc
.ontrack
= (event
) => {
176 console
.log(`track event is ${event}`)
177 let remoteRTPSenders
= cpc
.getSenders()
178 let remoteRTPReceivers
= cpc
.getReceivers()
179 console
.log(remoteRTPReceivers
)
180 /* Add each remoteRTPSenders.track to own stream */
181 let video
= document
.querySelector('video')
182 video
.autoplay
= true
184 hostScreen
= new MediaStream([remoteRTPReceivers
[0].track
])
185 if(!video
.srcObject
) {
186 video
.srcObject
= hostScreen
188 console
.log(hostScreen
.getVideoTracks())
189 console
.log(video
.srcObject
)
191 video
.onloadedmetadata
= () => {
195 dataChannel
.onmessage
= (msg
) => {
196 /* Get mediaStream from host and add it to the video */
197 let hostMessage
= JSON
.parse(msg
.data
)
198 cpc
.setRemoteDescription(hostMessage
.sdp
).then(() => {
199 cpc
.createAnswer().then((answer
) => {
200 return cpc
.setLocalDescription(answer
)
202 dataChannel
.send(JSON
.stringify({
203 "cmd": "> screen dataChannel",
204 "sdp": cpc
.localDescription
211 dataChannel
.onopen
= () => {
212 document
.body
.innerHTML
= (`<div><button> Connection with host established! </button></div> <video controls></video>`)
216 document
.addEventListener('DOMContentLoaded', () => {
218 document
.body
.innerHTML
= `<button> Setting up connection with host </button>`