Bug 174314 – RTCPeerConnection's close method should update signalingState

• Component: WebRTC
• Status: RESOLVED FIXED

[Mark Roberts]

Run the following code:

    (async () => {
      console.log('1. Constructing an RTCPeerConnection')
      const pc = new RTCPeerConnection()
      const signalingStateChangeEvent = new Promise(resolve => pc.onsignalingstatechange = resolve)
      console.log('2. Closing the RTCPeerConnection')
      pc.close()
      if (pc.signalingState !== 'closed') {
        console.error(`Expected the RTCPeerConnection's signaling state to be "closed", not "${pc.signalingState}"`)
      }
      console.log('3. Awaiting a "signalingstatechange" event')
      await signalingStateChangeEvent
      console.log('Success!')
    })()

Expected output (Chrome, Firefox):

    1. Constructing an RTCPeerConnection
    2. Closing the RTCPeerConnection
    3. Awaiting a "signalingstatechange" event
    Success!

Actual output (Safari):

    1. Constructing an RTCPeerConnection
    2. Closing the RTCPeerConnection
    Expected the RTCPeerConnection's signaling state to be "closed", not "stable"
    3. Awaiting a "signalingstatechange" event

In the actual output, "Success!" never prints because `signalingStateChangeEvent` never resolves. I guess the behavior around this was only recently specified here?

    https://github.com/w3c/webrtc-pc/pull/1371

[Mark Roberts]

RTCPeerConnection's `close` method should also update `iceConnectionState`. Perhaps this issue could be tracked here, too, instead of a separate ticket.

Run the following code:

    (async () => {
      console.log('1. Constructing an RTCPeerConnection')
      const pc = new RTCPeerConnection()
      const iceConnectionStateChangeEvent = new Promise(resolve => pc.oniceconnectionstatechange = resolve)
      console.log('2. Closing the RTCPeerConnection')
      pc.close()
      if (pc.iceConnectionState !== 'closed') {
        console.error(`Expected the RTCPeerConnection's ICE connection state to be "closed", not "${pc.iceConnectionState}"`)
      }
      console.log('3. Awaiting a "iceconnectionstatechange" event')
      await iceConnectionStateChangeEvent
      console.log('Success!')
    })()

Expected output (Firefox):

    1. Constructing an RTCPeerConnection
    2. Closing the RTCPeerConnection
    Expected the RTCPeerConnection's ICE connection state to be "closed", not "new"
    3. Awaiting a "iceconnectionstatechange" event
    Success!

Actual output (Safari):

    1. Constructing an RTCPeerConnection
    2. Closing the RTCPeerConnection
    Expected the RTCPeerConnection's ICE connection state to be "closed", not "new"
    3. Awaiting a "iceconnectionstatechange" event

In the actual output, "Success!" never prints because `iceConnectionStateChangeEvent` never resolves. This behavior seems specified in the Step 4 of `close` and the description of "closed" in RTCIceConnectionState:

    * http://w3c.github.io/webrtc-pc/#dom-rtcpeerconnection-close
    * http://w3c.github.io/webrtc-pc/#rtciceconnectionstate-enum

(Note: In Chrome, the error prints, too, I guess because `iceConnectionState` isn't updated synchronously?)

[Radar WebKit Bug Importer]

<rdar://problem/33267977>

[youenn fablet]

Thanks Mark, it is true we are missing the closed state.
I will add it. Looking at the spec, it does not seem to mandate firing an event though.
Maybe this is my reading of the spec.

[youenn fablet]

Testing further, you are right that Chrome and Firefox are firing this event.

[youenn fablet]

Created attachment 335605 [details]
Patch

[youenn fablet]

Filed https://github.com/w3c/webrtc-pc/issues/1799 for clarification about the event part of the bug.

[WebKit Commit Bot]

Comment on attachment 335605 [details]
Patch

Clearing flags on attachment: 335605

Committed r229548: <https://trac.webkit.org/changeset/229548>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.