var now1 = moment( moment().unix()*1000);   //获取unix时间戳 需要*1000

var befor_time =  moment(1470040905000)  ;   // 后台接口给的时间戳

//判断小时差

var hour_gap = now1.diff(befor_time,'hours');

if( hour_gap > 12) {

 var day=moment(befor_time).format("YYYY-MM-DD")  ;

 console.log(day)

 }else{

console.log(moment(befor_time).fromNow())

}