DOMException: "Failed to parse SDP: SDP Parse Error on line 6: No webrtc-datachannel token in m= media line, parse failed.

Seeing this error in firefox when calling peer.signal(offer). This is logged from from peer.on('error', (err) => {})

offer looks like:

{
  "type": "answer",
  "sdp": "v=0\no=- 2361903802410725008 2 IN IP4 127.0.0.1\r\ns=-\r\nt=0 0\r\na=msid-semantic: WMS\r\nm=application 0 UDP/DTLS/SCTP 5000\r\nc=IN IP4 0.0.0.0\r\na=mid:0\r\na=sctpmap:5000 webrtc-datachannel 1024\r\n"
}

It looks like m=application 0 UDP/DTLS/SCTP 5000. The \r\n carriage returns are concerning. I tried replacing them offer.sdp = offer.sdp.replace('\r\n', '\n'); with no luck.

This same handshake setup works in Chrome the crome answer looks like:

{
"type":"answer",
"sdp":"v=0\r\no=- 6148643454612116579 2 IN IP4 127.0.0.1\r\ns=-\r\nt=0 0\r\na=group:BUNDLE data\r\na=msid-semantic: WMS\r\nm=application 9 DTLS/SCTP 5000\r\nc=IN IP4 0.0.0.0\r\nb=AS:30\r\na=ice-ufrag:FC2g\r\na=ice-pwd:FAYzNn2P/NKl3nPazdVjK5Vj\r\na=fingerprint:sha-256 C6:33:30:F2:11:1D:FE:31:4D:F5:70:F3:6A:84:1B:98:36:EB:A3:D0:C1:DB:88:EC:24:52:EF:D1:1D:A0:F2:A7\r\na=setup:active\r\na=mid:data\r\na=sctpmap:5000 webrtc-datachannel 1024\r\n"
}

m here looks like m=application 9 DTLS/SCTP 5000

[kevzettler]

You’re connecting Firefox-to-Firefox correct? What do your peer options look like?

No. Firefox-to-Node.js

checkout https://stackoverflow.com/questions/54466865/firefox-webrtc-signaling-domexception-failed-to-parse-sdp

sounds like there is a breaking change between Firefox SDP parsing and the node.js wrtc module output. Going to close because don’t think its directly related to simple-peer.

[t-mullen]

Your offer is an not an offer but SDP answer (it says in the type field). It’s definitely not complete (missing a fingerprint for one). Can you double check that there isn’t a problem with your signalling setup?

You shouldn’t remove carriage returns, they’re correct.