This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
Deprecated
This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.
The RTCSessionDescription()
constructor creates a new RTCSessionDescription
with its properties initialized as described in the specified object.
This constructor has been deprecated because RTCPeerConnection.setLocalDescription()
and other methods which take SDP as input now directly accept an object conforming to the RTCSessionDescriptionInit
dictionary, so you don't have to instantiate an RTCSessionDescription
yourself.
Syntax
sessionDescription = new RTCSessionDescription(rtcSessionDescriptionInit);
Values
rtcSessionDescriptionInit
Optional- An object providing the default values for the session description; the object conforms to the
RTCSessionDescriptionInit
dictionary. That dictionary has the following properties:type
- Required. A string which is a member of the
RTCSdpType
enum; it must have one of the following values:This enum defines strings that describe the current state of the session description, as used in the
type
property. The session description's type will be specified using one of these values.Value Description answer
The SDP contained in the sdp
property is the definitive choice in the exchange. In other words, this session description describes the agreed-upon configuration, and is being sent to finalize negotiation.offer
The session description object describes the initial proposal in an offer/answer exchange. The session negotiation process begins with an offer being sent from the caller to the callee. pranswer
The session description object describes a provisional answer; that is, a response to a previous offer that is not the final answer. It is usually employed by legacy hardware. rollback
This special type with an empty session description is used to roll back to the previous stable state. sdp
- A string containing a SDP message describing the session. This value is an empty string (
""
) by default and may not benull
.
Example
This example uses the constructor to convert an SDP offer into an RTCSessionDescription
object.
This is no longer necessary, however; RTCPeerConnection.setLocalDescription()
and other methods which take SDP as input now directly accept an object conforming to the RTCSessionDescriptionInit
dictionary, so you don't have to instantiate an RTCSessionDescription
yourself.
navigator.getUserMedia({video: true}, function(stream) { pc.onaddstream({stream: stream}); // Adding a local stream won't trigger the onaddstream callback pc.addStream(stream); pc.createOffer(function(offer) { pc.setLocalDescription(new RTCSessionDescription(offer), function() { // send the offer to a server to be forwarded to the friend you're calling. }, error); }, error); }
Specifications
Specification | Status | Comment |
---|---|---|
WebRTC 1.0: Real-time Communication Between Browsers The definition of 'RTCSessionDescription()' in that specification. |
Candidate Recommendation | Initial specification. |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
RTCSessionDescription() constructor | Chrome Full support Yes | Edge Full support ≤18 | Firefox
Full support
Yes
| IE No support No | Opera ? | Safari ? | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android ? | Opera Android ? | Safari iOS ? | Samsung Internet Android Full support Yes |
Legend
- Full support
- Full support
- No support
- No support
- Compatibility unknown
- Compatibility unknown
- Experimental. Expect behavior to change in the future.
- Experimental. Expect behavior to change in the future.
- Deprecated. Not for use in new websites.
- Deprecated. Not for use in new websites.
- Requires a vendor prefix or different name for use.
- Requires a vendor prefix or different name for use.