sdp-jingle-json
Version:
A parser/serializer for SDP to JSON. Useful for converting SDP to other formats like Jingle for WebRTC signalling
226 lines (190 loc) • 7.41 kB
JavaScript
var SENDERS = require('./senders');
var parsers = require('./parsers');
var idCounter = Math.random();
exports._setIdCounter = function (counter) {
idCounter = counter;
};
exports.toSessionJSON = function (sdp, opts) {
var i;
var creators = opts.creators || [];
var role = opts.role || 'initiator';
var direction = opts.direction || 'outgoing';
// Divide the SDP into session and media sections.
var media = sdp.split(/\r?\nm=/);
for (i = 1; i < media.length; i++) {
media[i] = 'm=' + media[i];
if (i !== media.length - 1) {
media[i] += '\r\n';
}
}
var session = media.shift() + '\r\n';
var sessionLines = parsers.lines(session);
var parsed = {};
var contents = [];
for (i = 0; i < media.length; i++) {
contents.push(exports.toMediaJSON(media[i], session, {
role: role,
direction: direction,
creator: creators[i] || 'initiator'
}));
}
parsed.contents = contents;
var groupLines = parsers.findLines('a=group:', sessionLines);
if (groupLines.length) {
parsed.groups = parsers.groups(groupLines);
}
return parsed;
};
exports.toMediaJSON = function (media, session, opts) {
var creator = opts.creator || 'initiator';
var role = opts.role || 'initiator';
var direction = opts.direction || 'outgoing';
var lines = parsers.lines(media);
var sessionLines = parsers.lines(session);
var mline = parsers.mline(lines[0]);
var content = {
creator: creator,
name: mline.media,
application: {
applicationType: 'rtp',
media: mline.media,
payloads: [],
encryption: [],
feedback: [],
headerExtensions: []
},
transport: {
transportType: 'iceUdp',
candidates: [],
fingerprints: []
}
};
if (mline.media == 'application') {
// FIXME: the description is most likely to be independent
// of the SDP and should be processed by other parts of the library
content.application = {
applicationType: 'datachannel'
};
content.transport.sctp = [];
}
var desc = content.application;
var trans = content.transport;
// If we have a mid, use that for the content name instead.
var mid = parsers.findLine('a=mid:', lines);
if (mid) {
content.name = mid.substr(6);
}
if (parsers.findLine('a=sendrecv', lines, sessionLines)) {
content.senders = 'both';
} else if (parsers.findLine('a=sendonly', lines, sessionLines)) {
content.senders = SENDERS[role][direction].sendonly;
} else if (parsers.findLine('a=recvonly', lines, sessionLines)) {
content.senders = SENDERS[role][direction].recvonly;
} else if (parsers.findLine('a=inactive', lines, sessionLines)) {
content.senders = 'none';
}
if (desc.applicationType == 'rtp') {
var bandwidth = parsers.findLine('b=', lines);
if (bandwidth) {
desc.bandwidth = parsers.bandwidth(bandwidth);
}
var ssrc = parsers.findLine('a=ssrc:', lines);
if (ssrc) {
desc.ssrc = ssrc.substr(7).split(' ')[0];
}
var rtpmapLines = parsers.findLines('a=rtpmap:', lines);
rtpmapLines.forEach(function (line) {
var payload = parsers.rtpmap(line);
payload.parameters = [];
payload.feedback = [];
var fmtpLines = parsers.findLines('a=fmtp:' + payload.id, lines);
// There should only be one fmtp line per payload
fmtpLines.forEach(function (line) {
payload.parameters = parsers.fmtp(line);
});
var fbLines = parsers.findLines('a=rtcp-fb:' + payload.id, lines);
fbLines.forEach(function (line) {
payload.feedback.push(parsers.rtcpfb(line));
});
desc.payloads.push(payload);
});
var cryptoLines = parsers.findLines('a=crypto:', lines, sessionLines);
cryptoLines.forEach(function (line) {
desc.encryption.push(parsers.crypto(line));
});
if (parsers.findLine('a=rtcp-mux', lines)) {
desc.mux = true;
}
if (parsers.findLine('a=rtcp-rsize', lines)) {
desc.rsize = true;
}
var fbLines = parsers.findLines('a=rtcp-fb:*', lines);
fbLines.forEach(function (line) {
desc.feedback.push(parsers.rtcpfb(line));
});
var extLines = parsers.findLines('a=extmap:', lines);
extLines.forEach(function (line) {
var ext = parsers.extmap(line);
ext.senders = SENDERS[role][direction][ext.senders];
desc.headerExtensions.push(ext);
});
var ssrcGroupLines = parsers.findLines('a=ssrc-group:', lines);
desc.sourceGroups = parsers.sourceGroups(ssrcGroupLines || []);
var ssrcLines = parsers.findLines('a=ssrc:', lines);
var sources = desc.sources = parsers.sources(ssrcLines || []);
var msidLine = parsers.findLine('a=msid:', lines);
if (msidLine) {
var msid = parsers.msid(msidLine);
['msid', 'mslabel', 'label'].forEach(function (key) {
for (var i = 0; i < sources.length; i++) {
var found = false;
for (var j = 0; j < sources[i].parameters.length; j++) {
if (sources[i].parameters[j].key === key) {
found = true;
}
}
if (!found) {
sources[i].parameters.push({ key: key, value: msid[key] });
}
}
});
}
if (parsers.findLine('a=x-google-flag:conference', lines, sessionLines)) {
desc.googConferenceFlag = true;
}
}
// transport specific attributes
var fingerprintLines = parsers.findLines('a=fingerprint:', lines, sessionLines);
var setup = parsers.findLine('a=setup:', lines, sessionLines);
fingerprintLines.forEach(function (line) {
var fp = parsers.fingerprint(line);
if (setup) {
fp.setup = setup.substr(8);
}
trans.fingerprints.push(fp);
});
var ufragLine = parsers.findLine('a=ice-ufrag:', lines, sessionLines);
var pwdLine = parsers.findLine('a=ice-pwd:', lines, sessionLines);
if (ufragLine && pwdLine) {
trans.ufrag = ufragLine.substr(12);
trans.pwd = pwdLine.substr(10);
trans.candidates = [];
var candidateLines = parsers.findLines('a=candidate:', lines, sessionLines);
candidateLines.forEach(function (line) {
trans.candidates.push(exports.toCandidateJSON(line));
});
}
if (desc.applicationType == 'datachannel') {
var sctpmapLines = parsers.findLines('a=sctpmap:', lines);
sctpmapLines.forEach(function (line) {
var sctp = parsers.sctpmap(line);
trans.sctp.push(sctp);
});
}
return content;
};
exports.toCandidateJSON = function (line) {
var candidate = parsers.candidate(line.split(/\r?\n/)[0]);
candidate.id = (idCounter++).toString(36).substr(0, 12);
return candidate;
};