Your returned webrtc peerConnection Config is out of spec

Developers Cloudflare Calls
1

For Workers & Pages, what is the name of the domain?

NOT APPLICABLE

What is the issue or error you’re encountering

SEE BELOW. SEE BELOW. SEE BELOW. SEE BELOW. SEE BELOW. SEE BELOW. SEE BELOW.

What steps have you taken to resolve the issue?

Your webrtc peer connection config is out of spec.

when I call:

curl -X POST \ -H “Authorization: Bearer REMOVED” \ -H “Content-Type: application/json” -d ‘{“ttl”: 86400}’ \ https://rtc.live.cloudflare.com/v1/turn/keys/REMOVED/credentials/generate

you return:

{“iceServers”:{“urls”:[“stun:stun.cloudflare.com:3478”,”stun:stun.cloudflare.com:53”,”turn:turn.cloudflare.com:3478?transport=udp”,”turn:turn.cloudflare.com:53?transport=udp”,”turn:turn.cloudflare.com:3478?transport=tcp”,”turn:turn.cloudflare.com:80?transport=tcp”,”turns:turn.cloudflare.com:5349?transport=tcp”,”turns:turn.cloudflare.com:443?transport=tcp”],”username”:”REMOVED”,”credential”:”REMOVED”}}

when the webrtc spec requires the iceServers value must be an array.
see: RTCPeerConnection: RTCPeerConnection() constructor - Web APIs | MDN

For now I am having to work around this by transforming your invalid structure into a valid one.
I believe your intention is to be able to pass your response directly to the webrtc client, because your docs say such.
But it will crash if you do so right now.

This cannot be working for anyone currently.
Please wrap your returned iceServers value in an array.

What are the steps to reproduce the issue?

Your webrtc peer connection config is out of spec.

when I call:

curl -X POST \ -H “Authorization: Bearer REMOVED” \ -H “Content-Type: application/json” -d ‘{“ttl”: 86400}’ \ https://rtc.live.cloudflare.com/v1/turn/keys/REMOVED/credentials/generate

you return:

{“iceServers”:{“urls”:[“stun:stun.cloudflare.com:3478”,”stun:stun.cloudflare.com:53”,”turn:turn.cloudflare.com:3478?transport=udp”,”turn:turn.cloudflare.com:53?transport=udp”,”turn:turn.cloudflare.com:3478?transport=tcp”,”turn:turn.cloudflare.com:80?transport=tcp”,”turns:turn.cloudflare.com:5349?transport=tcp”,”turns:turn.cloudflare.com:443?transport=tcp”],”username”:”REMOVED”,”credential”:”REMOVED”}}

when the webrtc spec requires the iceServers value must be an array.
see: RTCPeerConnection: RTCPeerConnection() constructor - Web APIs | MDN

For now I am having to work around this by transforming your invalid structure into a valid one.
I believe your intention is to be able to pass your response directly to the webrtc client, because your docs say such.
But it will crash if you do so right now.

This cannot be working for anyone currently.
Please wrap your returned iceServers value in an array.

2

I’m doing a downstream conditional work around that will continue to work after you guys fix this.

for reference:

fetchPcConfig reaches to my backend and relays your return value to the client.

const fetchedPcConfig = await fetchPcConfig()

const patchedPcConfig = {
…fetchedPcConfig,
iceServers:
typeof fetchedPcConfig.iceServers === ‘object’
? [fetchedPcConfig.iceServers]
: fetchedPcConfig.iceServers
}

const peerConnection = new window.RTCPeerConnection(patchedPcConfig)

3

Yes that is a known limitation of the current credentials endpoint. We are working on a new endpoint without this limitation.