Sort firebase data in descending

javascript object sort desc.js

function sortDescObj(list, key) {
    var sortedKeys = Object.keys(list).sort(function(a,b) {
        return list[a][key] > list[b][key] ? -1:1
      });
    var newObjectSort = []
    var tem=[]
    for (let index = 0; index < sortedKeys.length; index++) {
        tem=[]
        newObjectSort.push(list[sortedKeys[index]])
    }
    return newObjectSort
}


//time: new Date().getTime(),
//firebase test get result sort time
contactsRef.orderByChild('time').on("value", function(snapshot) {
      allContacts = snapshot.val()
      var newObjectSort = sortDescObj(allContacts,'time')
      showContentContact(newObjectSort)
  }, function(errorObject) {
      console.log("The read failed: " + errorObject.code);
  });