A WebRTC error
event is sent to an RTCDataChannel
object's onerror
event handler when an error occurs on the data channel.
The RTCErrorEvent
object provides details about the error that occurred; see that article for details.
This event is not cancelable and does not bubble.
Use the event name in methods like addEventListener()
, or set an event handler property.
addEventListener("error", (event) => {});
onerror = (event) => {};
In addition to the properties listed below, properties from the parent interface, Event
, are available.
-
error
Read only
-
An RTCError
object specifying the error which occurred; this object includes the type of error that occurred, and information about where the error occurred (such as which line number in the SDP or what SCTP cause code was at issue).
const sctpCauseCodes = [
"No SCTP error",
"Invalid stream identifier",
"Missing mandatory parameter",
"Stale cookie error",
"Sender is out of resource (i.e., memory)",
"Unable to resolve address",
"Unrecognized SCTP chunk type received",
"Invalid mandatory parameter",
"Unrecognized parameters",
"No user data (SCTP DATA chunk has no data)",
"Cookie received while shutting down",
"Restart of an association with new addresses",
"User-initiated abort",
"Protocol violation",
];
dc.addEventListener(
"error",
(ev) => {
const err = ev.error;
console.error("WebRTC error: ", err.message);
switch (err.errorDetail) {
case "sdp-syntax-error":
console.error(" SDP syntax error in line ", err.sdpLineNumber);
break;
case "idp-load-failure":
console.error(
" Identity provider load failure: HTTP error ",
err.httpRequestStatusCode,
);
break;
case "sctp-failure":
if (err.sctpCauseCode < sctpCauseCodes.length) {
console.error(" SCTP failure: ", err.sctpCauseCode);
} else {
console.error(" Unknown SCTP error");
}
break;
case "dtls-failure":
if (err.receivedAlert) {
console.error(" Received DLTS failure alert: ", err.receivedAlert);
}
if (err.sentAlert) {
console.error(" Sent DLTS failure alert: ", err.receivedAlert);
}
break;
}
console.error(
" Error in file ",
err.filename,
" at line ",
err.lineNumber,
", column ",
err.columnNumber,
);
},
false,
);
The received event provides details in an RTCError
object called error
; RTCError
is an extension of the DOMException
interface. The error's name
is RTCError
and the message
is an error string specified by the WebRTC layer.
Error information is output to the console using console.error()
. The message
string is always output, as is information about the source file's name, line number, and column number at which the error occurred.
In addition, however, depending on the value of errorDetail
, additional information may be output. Each error type has a different set of information output. For example, an SDP syntax error displays the line number of the error within the SDP, and an SCTP error displays a message corresponding to the SCTP cause code. Other error types similarly output appropriate information.
You can also set up an event handler for error
events using the RTCDataChannel
interface's onerror
event handler property:
dc.onerror = (ev) => {
const err = ev.error;
};
Note: Since RTCError
is not one of the legacy errors, the value of RTCError.code
is always 0.