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Re: Suggestion: Less verbose syntax for offer/answer handling

From: Justin Uberti <juberti@google.com>
Date: Tue, 5 Jun 2012 11:46:59 -0400
Message-ID: <CAOJ7v-2DL_taz+MDG8FNtOVcdaazPO_ypvAe7LHzH0vSeWA2nQ@mail.gmail.com>
To: Eric Rescorla <ekr@rtfm.com>
Cc: Adam Bergkvist <adam.bergkvist@ericsson.com>, "public-webrtc@w3.org" <public-webrtc@w3.org>
If we do this, updateRemoteDescription needs to be able to take either an
IceCandidate or a SessionDescription. These types are not interchangeable;
the IceCandidate needs to have an additional field to indicate which m-line
it's associated with.

On Tue, Jun 5, 2012 at 11:08 AM, Eric Rescorla <ekr@rtfm.com> wrote:

> I'm pretty indifferent to these options, but is there any other
> advantage to this
> other than JS compactness?
>
> -Ekr
>
>
> On Tue, Jun 5, 2012 at 6:58 AM, Adam Bergkvist
> <adam.bergkvist@ericsson.com> wrote:
> > Hi
> >
> > This suggestion uses the SdpType attribute of SessionDescription
> (discussed
> > in:
> > http://lists.w3.org/Archives/Public/public-webrtc/2012May/0047.html) to
> > include type information in the SessionDescription object. By doing so,
> we
> > can have a less verbose syntax where the JavaScript developer can work
> with
> > self-contained objects that are generated and understood by
> PeerConnection.
> >
> > This doesn't reduce flexibility since the application can reset the type
> of,
> > e.g., an "answer" to an "pranswer" to make PeerConnection interpret it as
> > such.
> >
> > Example of creating an offer:
> >
> > --- Current syntax:
> >
> > pc.createOffer(function (offer) {
> >    pc.setLocalDescription("offer", offer);
> >    sendMessage(JSON.stringify({ "type": "offer", "sdp": offer }));
> > });
> >
> > --- Less verbose syntax:
> >
> > pc.createOffer(function (offer) {
> >    pc.updateLocalDescription(offer);
> >    sendMessage(offer);
> > });
> >
> > Example of handling an incoming signaling message:
> >
> > --- Current syntax:
> >
> > signalingChannel.onmessage = function (evt) {
> >    var msg = JSON.parse(evt.data);
> >    switch (msg.type) {
> >    case "offer":
> >        createPeerConnection();
> >        pc.setRemoteDescription(msg.type,
> >                                new SessionDescription(msg.sdp));
> >        break;
> >    case "answer":
> >    case "pranswer":
> >        pc.setRemoteDescription(msg.type,
> >                                new SessionDescription(msg.sdp));
> >        break;
> >    case "candidate":
> >        pc.addIceCandidate(new IceCandidate(msg.sdp));
> >        break;
> >    }
> > };
> >
> > --- Less verbose syntax:
> >
> > signalingChannel.onmessage = function (evt) {
> >    if (!pc)
> >        createPeerConnection();
> >
> >    pc.updateRemoteDescription(evt.data);
> > };
> >
> > /Adam
> >
>
>
Received on Tuesday, 5 June 2012 15:53:27 UTC

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