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@johnnymillergh
Forked from hectorguo/getLocalIP.js
Created July 7, 2019 01:48
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Get local IP address through Javascript
/**
* Get Local IP Address
*
* @returns Promise Object
*
* getLocalIP().then((ipAddr) => {
* console.log(ipAddr); // 192.168.0.122
* });
*/
function getLocalIP() {
return new Promise(function(resolve, reject) {
// NOTE: window.RTCPeerConnection is "not a constructor" in FF22/23
var RTCPeerConnection = /*window.RTCPeerConnection ||*/ window.webkitRTCPeerConnection || window.mozRTCPeerConnection;
if (!RTCPeerConnection) {
reject('Your browser does not support this API');
}
var rtc = new RTCPeerConnection({iceServers:[]});
var addrs = {};
addrs["0.0.0.0"] = false;
function grepSDP(sdp) {
var hosts = [];
var finalIP = '';
sdp.split('\r\n').forEach(function (line) { // c.f. http://tools.ietf.org/html/rfc4566#page-39
if (~line.indexOf("a=candidate")) { // http://tools.ietf.org/html/rfc4566#section-5.13
var parts = line.split(' '), // http://tools.ietf.org/html/rfc5245#section-15.1
addr = parts[4],
type = parts[7];
if (type === 'host') {
finalIP = addr;
}
} else if (~line.indexOf("c=")) { // http://tools.ietf.org/html/rfc4566#section-5.7
var parts = line.split(' '),
addr = parts[2];
finalIP = addr;
}
});
return finalIP;
}
if (1 || window.mozRTCPeerConnection) { // FF [and now Chrome!] needs a channel/stream to proceed
rtc.createDataChannel('', {reliable:false});
};
rtc.onicecandidate = function (evt) {
// convert the candidate to SDP so we can run it through our general parser
// see https://twitter.com/lancestout/status/525796175425720320 for details
if (evt.candidate) {
var addr = grepSDP("a="+evt.candidate.candidate);
resolve(addr);
}
};
rtc.createOffer(function (offerDesc) {
rtc.setLocalDescription(offerDesc);
}, function (e) { console.warn("offer failed", e); });
});
}
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