Node.js 获取客户端IP

//获取url请求客户端ipvar get_client_ip = function(req) {    var ip = req.headers['x-forwarded-for'] ||        req.ip ||        req.connection.remoteAddress ||        req.socket.remoteAddress ||        req.connection.socket.remoteAddress || '';    if(ip.split(',').length>0){        ip = ip.split(',')[0]    }    return ip;};