本機のIPアドレスの取得例（JavaScript/Node.js）
--webクライアントJavaScript
<!-- -->
<body onload="checkCookie()"></body>
function getYourIP()
{
const RTCPeerConnection = window.RTCPeerConnection || window.webkitRTCPeerConnection || window.mozRTCPeerConnection;
if (RTCPeerConnection) (function()
{
const rtc = new RTCPeerConnection({iceServers: []});
if (1 || window.mozRTCPeerConnection)
{
rtc.createDataChannel('', {reliable: false});
}
rtc.onicecandidate = function(evt)
{
if (evt.candidate) grepSDP(`a=${evt.candidate.candidate}`);
};
rtc.createOffer(function(offerDesc)
{
grepSDP(offerDesc.sdp);
rtc.setLocalDescription(offerDesc);
}, function(e) {console.warn('offer failed', e);});
const addrs = Object.create(null);
addrs['0.0.0.0'] = false;
function updateDisplay(newAddr)
{
if (newAddr in addrs) return;
addrs[newAddr] = true;
const displayAddrs = Object.keys(addrs).filter(function(k) {return addrs[k];});
for (let i = 0; i < displayAddrs.length; i++)
{
if (displayAddrs[i].length > 16)
{
displayAddrs.splice(i, 1);
i--;
}
}
console.info(' IP: ', displayAddrs[0]);
}
function grepSDP(sdp)
{
sdp.split('\r
').forEach(function(line, index, arr)
{
if (~line.indexOf('a=candidate'))
{
const parts = line.split(' '),
addr = parts[4],
type = parts[7];
if (type === 'host') updateDisplay(addr);
}
else if (~line.indexOf('c='))
{
const parts = line.split(' '),
addr = parts[2];
updateDisplay(addr);
}
});
}
})();
else
{
console.warn(' ：chrome,firefox,opera,safari');
}
}
const os = require('os');
module.exports =
{
getLocalIP : function()
{
const eth0 = os.networkInterfaces().eth0;
let localhost = null;
for (let i = 0; i < eth0.length; i++)
{
if (eth0[i].family == 'IPv4')
{
localhost = eth0[i].address;
}
}
return localhost;
},
};